1995-07-20 07:43:20 +00:00
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1997-05-16 07:46:07 +00:00
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/* pngwutil.c - utilities to write a PNG file
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1998-01-01 13:13:13 +00:00
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*
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* libpng 1.00.97
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* For conditions of distribution and use, see copyright notice in png.h
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* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
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* Copyright (c) 1996, 1997 Andreas Dilger
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* May 28, 1997
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*/
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1997-05-16 07:46:07 +00:00
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1995-07-20 07:43:20 +00:00
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#define PNG_INTERNAL
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#include "png.h"
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1997-05-16 07:46:07 +00:00
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/* Place a 32-bit number into a buffer in PNG byte order. We work
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* with unsigned numbers for convenience, although one supported
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* ancillary chunk uses signed (two's complement) numbers.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1995-12-19 09:22:19 +00:00
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png_save_uint_32(png_bytep buf, png_uint_32 i)
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1995-07-20 07:43:20 +00:00
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{
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buf[0] = (png_byte)((i >> 24) & 0xff);
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buf[1] = (png_byte)((i >> 16) & 0xff);
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buf[2] = (png_byte)((i >> 8) & 0xff);
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buf[3] = (png_byte)(i & 0xff);
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}
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1997-05-16 07:46:07 +00:00
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#if defined(PNG_WRITE_pCAL_SUPPORTED)
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/* The png_save_int_32 function assumes integers are stored in two's
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1998-01-01 13:13:13 +00:00
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* complement format. If this isn't the case, then this routine needs to
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* be modified to write data in two's complement format.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1997-05-16 07:46:07 +00:00
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png_save_int_32(png_bytep buf, png_int_32 i)
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1995-07-20 07:43:20 +00:00
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{
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buf[0] = (png_byte)((i >> 24) & 0xff);
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buf[1] = (png_byte)((i >> 16) & 0xff);
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buf[2] = (png_byte)((i >> 8) & 0xff);
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buf[3] = (png_byte)(i & 0xff);
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}
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1997-05-16 07:46:07 +00:00
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#endif
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1995-07-20 07:43:20 +00:00
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1998-01-01 13:13:13 +00:00
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/* Place a 16-bit number into a buffer in PNG byte order.
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* The parameter is declared unsigned int, not png_uint_16,
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* just to avoid potential problems on pre-ANSI C compilers.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1998-01-01 13:13:13 +00:00
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png_save_uint_16(png_bytep buf, unsigned int i)
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1995-07-20 07:43:20 +00:00
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{
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buf[0] = (png_byte)((i >> 8) & 0xff);
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buf[1] = (png_byte)(i & 0xff);
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}
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1997-05-16 07:46:07 +00:00
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/* Write a PNG chunk all at once. The type is an array of ASCII characters
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1998-01-01 13:13:13 +00:00
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* representing the chunk name. The array must be at least 4 bytes in
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* length, and does not need to be null terminated. To be safe, pass the
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* pre-defined chunk names here, and if you need a new one, define it
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* where the others are defined. The length is the length of the data.
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* All the data must be present. If that is not possible, use the
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* png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
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* functions instead.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1997-01-17 07:34:35 +00:00
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png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
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1997-05-16 07:46:07 +00:00
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png_bytep data, png_size_t length)
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1995-07-20 07:43:20 +00:00
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{
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1997-05-16 07:46:07 +00:00
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png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
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1997-01-17 07:34:35 +00:00
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png_write_chunk_data(png_ptr, data, length);
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png_write_chunk_end(png_ptr);
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1995-07-20 07:43:20 +00:00
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}
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1997-05-16 07:46:07 +00:00
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/* Write the start of a PNG chunk. The type is the chunk type.
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1998-01-01 13:13:13 +00:00
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* The total_length is the sum of the lengths of all the data you will be
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* passing in png_write_chunk_data().
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*/
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1995-07-20 07:43:20 +00:00
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void
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1997-01-17 07:34:35 +00:00
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png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
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png_uint_32 length)
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1995-07-20 07:43:20 +00:00
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{
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1997-05-16 07:46:07 +00:00
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png_byte buf[4];
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png_debug2(0, "Writing %s chunk (%d bytes)\n", chunk_name, length);
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1995-07-20 07:43:20 +00:00
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/* write the length */
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1997-05-16 07:46:07 +00:00
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png_save_uint_32(buf, length);
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png_write_data(png_ptr, buf, (png_size_t)4);
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1995-07-20 07:43:20 +00:00
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/* write the chunk name */
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1997-05-16 07:46:07 +00:00
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png_write_data(png_ptr, chunk_name, (png_size_t)4);
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1995-07-20 07:43:20 +00:00
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/* reset the crc and run it over the chunk name */
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png_reset_crc(png_ptr);
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1997-05-16 07:46:07 +00:00
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png_calculate_crc(png_ptr, chunk_name, (png_size_t)4);
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1995-07-20 07:43:20 +00:00
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}
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1997-05-16 07:46:07 +00:00
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/* Write the data of a PNG chunk started with png_write_chunk_start().
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1998-01-01 13:13:13 +00:00
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* Note that multiple calls to this function are allowed, and that the
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* sum of the lengths from these calls *must* add up to the total_length
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* given to png_write_chunk_start().
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*/
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1995-07-20 07:43:20 +00:00
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void
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1997-05-16 07:46:07 +00:00
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png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
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1995-07-20 07:43:20 +00:00
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{
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1997-05-16 07:46:07 +00:00
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/* write the data, and run the CRC over it */
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if (data != NULL && length > 0)
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1995-07-20 07:43:20 +00:00
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{
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png_calculate_crc(png_ptr, data, length);
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1995-12-19 09:22:19 +00:00
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png_write_data(png_ptr, data, length);
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1995-07-20 07:43:20 +00:00
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}
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}
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1997-05-16 07:46:07 +00:00
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/* Finish a chunk started with png_write_chunk_start(). */
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1995-07-20 07:43:20 +00:00
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void
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1995-12-19 09:22:19 +00:00
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png_write_chunk_end(png_structp png_ptr)
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1995-07-20 07:43:20 +00:00
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{
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1997-05-16 07:46:07 +00:00
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png_byte buf[4];
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1995-07-20 07:43:20 +00:00
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/* write the crc */
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1997-05-16 07:46:07 +00:00
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png_save_uint_32(buf, png_ptr->crc);
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png_write_data(png_ptr, buf, (png_size_t)4);
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1995-07-20 07:43:20 +00:00
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}
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1997-01-17 07:34:35 +00:00
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/* Simple function to write the signature. If we have already written
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* the magic bytes of the signature, or more likely, the PNG stream is
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* being embedded into another stream and doesn't need its own signature,
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* we should call png_set_sig_bytes() to tell libpng how many of the
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1998-01-01 13:13:13 +00:00
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* bytes have already been written.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1995-12-19 09:22:19 +00:00
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png_write_sig(png_structp png_ptr)
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1995-07-20 07:43:20 +00:00
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{
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1997-01-17 07:34:35 +00:00
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/* write the rest of the 8 byte signature */
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png_write_data(png_ptr, &png_sig[png_ptr->sig_bytes],
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1997-05-16 07:46:07 +00:00
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(png_size_t)8 - png_ptr->sig_bytes);
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1995-07-20 07:43:20 +00:00
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}
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/* Write the IHDR chunk, and update the png_struct with the necessary
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1998-01-01 13:13:13 +00:00
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* information. Note that the rest of this code depends upon this
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* information being correct.
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*/
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1995-07-20 07:43:20 +00:00
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void
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1995-12-19 09:22:19 +00:00
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png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
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1995-07-20 07:43:20 +00:00
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int bit_depth, int color_type, int compression_type, int filter_type,
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int interlace_type)
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{
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png_byte buf[13]; /* buffer to store the IHDR info */
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1997-05-16 07:46:07 +00:00
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png_debug(1, "in png_write_IHDR\n");
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1996-06-05 20:50:50 +00:00
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/* Check that we have valid input data from the application info */
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1995-07-20 07:43:20 +00:00
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switch (color_type)
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{
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1997-05-16 07:46:07 +00:00
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case PNG_COLOR_TYPE_GRAY:
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1996-06-05 20:50:50 +00:00
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switch (bit_depth)
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{
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case 1:
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case 2:
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case 4:
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case 8:
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case 16: png_ptr->channels = 1; break;
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1997-05-16 07:46:07 +00:00
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default: png_error(png_ptr,"Invalid bit depth for grayscale image");
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1996-06-05 20:50:50 +00:00
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}
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1995-07-20 07:43:20 +00:00
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break;
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1997-05-16 07:46:07 +00:00
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case PNG_COLOR_TYPE_RGB:
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1996-06-05 20:50:50 +00:00
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for RGB image");
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1995-07-20 07:43:20 +00:00
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png_ptr->channels = 3;
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break;
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1997-05-16 07:46:07 +00:00
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case PNG_COLOR_TYPE_PALETTE:
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1996-06-05 20:50:50 +00:00
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switch (bit_depth)
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{
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case 1:
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case 2:
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case 4:
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case 8: png_ptr->channels = 1; break;
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default: png_error(png_ptr, "Invalid bit depth for paletted image");
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}
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break;
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1997-05-16 07:46:07 +00:00
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case PNG_COLOR_TYPE_GRAY_ALPHA:
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1996-06-05 20:50:50 +00:00
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
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1995-07-20 07:43:20 +00:00
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png_ptr->channels = 2;
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break;
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1997-05-16 07:46:07 +00:00
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case PNG_COLOR_TYPE_RGB_ALPHA:
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1996-06-05 20:50:50 +00:00
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for RGBA image");
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1995-07-20 07:43:20 +00:00
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png_ptr->channels = 4;
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break;
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1996-06-05 20:50:50 +00:00
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default:
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png_error(png_ptr, "Invalid image color type specified");
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}
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1997-05-16 07:46:07 +00:00
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if (compression_type != PNG_COMPRESSION_TYPE_BASE)
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1996-06-05 20:50:50 +00:00
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{
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png_warning(png_ptr, "Invalid compression type specified");
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1997-05-16 07:46:07 +00:00
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compression_type = PNG_COMPRESSION_TYPE_BASE;
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1996-06-05 20:50:50 +00:00
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}
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1997-05-16 07:46:07 +00:00
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if (filter_type != PNG_FILTER_TYPE_BASE)
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1996-06-05 20:50:50 +00:00
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{
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png_warning(png_ptr, "Invalid filter type specified");
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1997-05-16 07:46:07 +00:00
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filter_type = PNG_FILTER_TYPE_BASE;
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1996-06-05 20:50:50 +00:00
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}
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1997-05-16 07:46:07 +00:00
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if (interlace_type != PNG_INTERLACE_NONE &&
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interlace_type != PNG_INTERLACE_ADAM7)
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1996-06-05 20:50:50 +00:00
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{
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png_warning(png_ptr, "Invalid interlace type specified");
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1997-05-16 07:46:07 +00:00
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interlace_type = PNG_INTERLACE_ADAM7;
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1995-07-20 07:43:20 +00:00
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}
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1996-06-05 20:50:50 +00:00
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/* save off the relevent information */
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png_ptr->bit_depth = (png_byte)bit_depth;
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png_ptr->color_type = (png_byte)color_type;
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png_ptr->interlaced = (png_byte)interlace_type;
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png_ptr->width = width;
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png_ptr->height = height;
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1996-01-26 07:38:47 +00:00
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png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
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1997-05-16 07:46:07 +00:00
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png_ptr->rowbytes = ((width * (png_size_t)png_ptr->pixel_depth + 7) >> 3);
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1995-07-20 07:43:20 +00:00
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/* set the usr info, so any transformations can modify it */
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png_ptr->usr_width = png_ptr->width;
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png_ptr->usr_bit_depth = png_ptr->bit_depth;
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1996-06-05 20:50:50 +00:00
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png_ptr->usr_channels = png_ptr->channels;
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/* pack the header information into the buffer */
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png_save_uint_32(buf, width);
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png_save_uint_32(buf + 4, height);
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buf[8] = (png_byte)bit_depth;
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buf[9] = (png_byte)color_type;
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buf[10] = (png_byte)compression_type;
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buf[11] = (png_byte)filter_type;
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buf[12] = (png_byte)interlace_type;
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1995-07-20 07:43:20 +00:00
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/* write the chunk */
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1997-05-16 07:46:07 +00:00
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png_write_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
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1995-09-26 10:22:39 +00:00
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1997-05-16 07:46:07 +00:00
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/* initialize zlib with PNG info */
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1997-01-17 07:34:35 +00:00
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png_ptr->zstream.zalloc = png_zalloc;
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png_ptr->zstream.zfree = png_zfree;
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png_ptr->zstream.opaque = (voidpf)png_ptr;
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1996-06-05 20:50:50 +00:00
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if (!(png_ptr->do_filter))
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1995-09-26 10:22:39 +00:00
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{
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1997-05-16 07:46:07 +00:00
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if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
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png_ptr->bit_depth < 8)
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1996-06-05 20:50:50 +00:00
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png_ptr->do_filter = PNG_FILTER_NONE;
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1995-09-26 10:22:39 +00:00
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else
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1996-06-05 20:50:50 +00:00
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png_ptr->do_filter = PNG_ALL_FILTERS;
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1995-09-26 10:22:39 +00:00
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}
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1996-06-05 20:50:50 +00:00
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if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY))
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1995-09-26 10:22:39 +00:00
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{
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1996-06-05 20:50:50 +00:00
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if (png_ptr->do_filter != PNG_FILTER_NONE)
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1995-09-26 10:22:39 +00:00
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png_ptr->zlib_strategy = Z_FILTERED;
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else
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png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY;
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}
|
1996-06-05 20:50:50 +00:00
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if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL))
|
1995-09-26 10:22:39 +00:00
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png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
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1996-06-05 20:50:50 +00:00
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if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL))
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1995-09-26 10:22:39 +00:00
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png_ptr->zlib_mem_level = 8;
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1996-06-05 20:50:50 +00:00
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if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS))
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1995-09-26 10:22:39 +00:00
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|
|
png_ptr->zlib_window_bits = 15;
|
1996-06-05 20:50:50 +00:00
|
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
|
1995-09-26 10:22:39 +00:00
|
|
|
png_ptr->zlib_method = 8;
|
1997-01-17 07:34:35 +00:00
|
|
|
deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->zlib_method, png_ptr->zlib_window_bits,
|
|
|
|
png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->mode = PNG_HAVE_IHDR;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* write the palette. We are careful not to trust png_color to be in the
|
1998-01-01 13:13:13 +00:00
|
|
|
* correct order for PNG, so people can redefine it to any convient
|
|
|
|
* structure.
|
|
|
|
*/
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 i;
|
1996-01-26 07:38:47 +00:00
|
|
|
png_colorp pal_ptr;
|
1995-07-20 07:43:20 +00:00
|
|
|
png_byte buf[3];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_PLTE\n");
|
|
|
|
if (num_pal == 0 || num_pal > 256)
|
1996-06-05 20:50:50 +00:00
|
|
|
{
|
|
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
|
|
{
|
|
|
|
png_error(png_ptr, "Invalid number of colors in palette");
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid number of colors in palette");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->num_palette = (png_uint_16)num_pal;
|
|
|
|
png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_start(png_ptr, png_PLTE, num_pal * 3);
|
|
|
|
for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
buf[0] = pal_ptr->red;
|
|
|
|
buf[1] = pal_ptr->green;
|
|
|
|
buf[2] = pal_ptr->blue;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)3);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
png_write_chunk_end(png_ptr);
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->mode |= PNG_HAVE_PLTE;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* write an IDAT chunk */
|
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_IDAT\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
png_write_chunk(png_ptr, png_IDAT, data, length);
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->mode |= PNG_HAVE_IDAT;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* write an IEND chunk */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_IEND(png_structp png_ptr)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_IEND\n");
|
|
|
|
png_write_chunk(png_ptr, png_IEND, NULL, (png_size_t)0);
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->mode |= PNG_HAVE_IEND;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_gAMA_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write a gAMA chunk */
|
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_gAMA(png_structp png_ptr, double file_gamma)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_uint_32 igamma;
|
|
|
|
png_byte buf[4];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_gAMA\n");
|
|
|
|
/* file_gamma is saved in 1/100,000ths */
|
|
|
|
igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5);
|
1995-07-20 07:43:20 +00:00
|
|
|
png_save_uint_32(buf, igamma);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1998-01-01 13:13:13 +00:00
|
|
|
#if defined(PNG_WRITE_sRGB_SUPPORTED)
|
|
|
|
/* write a sRGB chunk */
|
|
|
|
void
|
|
|
|
png_write_sRGB(png_structp png_ptr, png_byte srgb_intent)
|
|
|
|
{
|
|
|
|
png_byte buf[1];
|
|
|
|
|
|
|
|
png_debug(1, "in png_write_sRGB\n");
|
|
|
|
if(srgb_intent > 3)
|
|
|
|
png_warning(png_ptr,
|
|
|
|
"Invalid sRGB rendering intent specified");
|
|
|
|
buf[0]=srgb_intent;
|
|
|
|
png_write_chunk(png_ptr, png_sRGB, buf, (png_size_t)1);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_sBIT_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the sBIT chunk */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_byte buf[4];
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t size;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_sBIT\n");
|
1995-12-19 09:22:19 +00:00
|
|
|
/* make sure we don't depend upon the order of PNG_COLOR_8 */
|
1995-07-20 07:43:20 +00:00
|
|
|
if (color_type & PNG_COLOR_MASK_COLOR)
|
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
int maxbits;
|
|
|
|
|
|
|
|
maxbits = color_type==PNG_COLOR_TYPE_PALETTE ? 8:png_ptr->usr_bit_depth;
|
|
|
|
if (sbit->red == 0 || sbit->red > maxbits ||
|
|
|
|
sbit->green == 0 || sbit->green > maxbits ||
|
|
|
|
sbit->blue == 0 || sbit->blue > maxbits)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
buf[0] = sbit->red;
|
|
|
|
buf[1] = sbit->green;
|
|
|
|
buf[2] = sbit->blue;
|
|
|
|
size = 3;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
buf[0] = sbit->gray;
|
|
|
|
size = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (color_type & PNG_COLOR_MASK_ALPHA)
|
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
buf[size++] = sbit->alpha;
|
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_sBIT, buf, size);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_cHRM_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the cHRM chunk */
|
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
|
1996-01-26 07:38:47 +00:00
|
|
|
double red_x, double red_y, double green_x, double green_y,
|
|
|
|
double blue_x, double blue_y)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_uint_32 itemp;
|
|
|
|
png_byte buf[32];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_cHRM\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
/* each value is saved int 1/100,000ths */
|
1996-06-05 20:50:50 +00:00
|
|
|
if (white_x < 0 || white_x > 0.8 || white_y < 0 || white_y > 0.8 ||
|
|
|
|
white_x + white_y > 1.0)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid cHRM white point specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
itemp = (png_uint_32)(white_x * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf, itemp);
|
|
|
|
itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 4, itemp);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
if (red_x < 0 || red_x > 0.8 || red_y < 0 || red_y > 0.8 ||
|
|
|
|
red_x + red_y > 1.0)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid cHRM red point specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
itemp = (png_uint_32)(red_x * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 8, itemp);
|
|
|
|
itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 12, itemp);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
if (green_x < 0 || green_x > 0.8 || green_y < 0 || green_y > 0.8 ||
|
|
|
|
green_x + green_y > 1.0)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid cHRM green point specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
itemp = (png_uint_32)(green_x * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 16, itemp);
|
|
|
|
itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 20, itemp);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
if (blue_x < 0 || blue_x > 0.8 || blue_y < 0 || blue_y > 0.8 ||
|
|
|
|
blue_x + blue_y > 1.0)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid cHRM blue point specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
itemp = (png_uint_32)(blue_x * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 24, itemp);
|
|
|
|
itemp = (png_uint_32)(blue_y * 100000.0 + 0.5);
|
|
|
|
png_save_uint_32(buf + 28, itemp);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_cHRM, buf, (png_size_t)32);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_tRNS_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the tRNS chunk */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
|
1995-07-20 07:43:20 +00:00
|
|
|
int num_trans, int color_type)
|
|
|
|
{
|
|
|
|
png_byte buf[6];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_tRNS\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
if (color_type == PNG_COLOR_TYPE_PALETTE)
|
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
if (num_trans <= 0 || num_trans > png_ptr->num_palette)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr,"Invalid number of transparent colors specified");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the chunk out as it is */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_tRNS, trans, (png_size_t)num_trans);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
else if (color_type == PNG_COLOR_TYPE_GRAY)
|
|
|
|
{
|
|
|
|
/* one 16 bit value */
|
|
|
|
png_save_uint_16(buf, tran->gray);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)2);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
else if (color_type == PNG_COLOR_TYPE_RGB)
|
|
|
|
{
|
|
|
|
/* three 16 bit values */
|
|
|
|
png_save_uint_16(buf, tran->red);
|
|
|
|
png_save_uint_16(buf + 2, tran->green);
|
|
|
|
png_save_uint_16(buf + 4, tran->blue);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)6);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1996-06-05 20:50:50 +00:00
|
|
|
else
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Can't write tRNS with and alpha channel");
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_bKGD_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the background chunk */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_byte buf[6];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_bKGD\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
if (color_type == PNG_COLOR_TYPE_PALETTE)
|
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
if (back->index > png_ptr->num_palette)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid background palette index");
|
|
|
|
return;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
buf[0] = back->index;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
else if (color_type & PNG_COLOR_MASK_COLOR)
|
|
|
|
{
|
|
|
|
png_save_uint_16(buf, back->red);
|
|
|
|
png_save_uint_16(buf + 2, back->green);
|
|
|
|
png_save_uint_16(buf + 4, back->blue);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)6);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
else
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
1995-07-20 07:43:20 +00:00
|
|
|
png_save_uint_16(buf, back->gray);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)2);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_hIST_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write the histogram */
|
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_hIST(png_structp png_ptr, png_uint_16p hist, png_uint_32 num_hist)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 i;
|
1995-07-20 07:43:20 +00:00
|
|
|
png_byte buf[3];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_hIST\n");
|
|
|
|
if (num_hist > png_ptr->num_palette)
|
1996-06-05 20:50:50 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist,
|
|
|
|
png_ptr->num_palette);
|
1996-06-05 20:50:50 +00:00
|
|
|
png_warning(png_ptr, "Invalid number of histogram entries specified");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_start(png_ptr, png_hIST, num_hist * 2);
|
|
|
|
for (i = 0; i < num_hist; i++)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1996-01-26 07:38:47 +00:00
|
|
|
png_save_uint_16(buf, hist[i]);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)2);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-01-17 07:34:35 +00:00
|
|
|
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
|
|
|
|
/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
|
|
|
|
* and if invalid, correct the keyword rather than discarding the entire
|
|
|
|
* chunk. The PNG 1.0 specification requires keywords 1-79 characters in
|
|
|
|
* length, forbids leading or trailing whitespace, multiple internal spaces,
|
|
|
|
* and the non-break space (0x80) from ISO 8859-1. Returns keyword length.
|
1997-05-16 07:46:07 +00:00
|
|
|
*
|
|
|
|
* The new_key is allocated to hold the corrected keyword and must be freed
|
|
|
|
* by the calling routine. This avoids problems with trying to write to
|
|
|
|
* static keywords without having to have duplicate copies of the strings.
|
1997-01-17 07:34:35 +00:00
|
|
|
*/
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t
|
1998-01-01 13:13:13 +00:00
|
|
|
png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t key_len;
|
1998-01-01 13:13:13 +00:00
|
|
|
png_charp kp, dp;
|
1997-01-17 07:34:35 +00:00
|
|
|
int kflag;
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_check_keyword\n");
|
|
|
|
*new_key = NULL;
|
|
|
|
|
|
|
|
if (key == NULL || (key_len = png_strlen(key)) == 0)
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
|
|
|
char msg[40];
|
|
|
|
|
|
|
|
sprintf(msg, "Zero length %s keyword", png_ptr->chunk_name);
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
return 0;
|
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
png_debug1(2, "Keyword to be checked is '%s'\n", key);
|
|
|
|
|
1998-01-01 13:13:13 +00:00
|
|
|
*new_key = (png_charp)png_malloc(png_ptr, key_len + 1);
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
/* Replace non-printing characters with a blank and print a warning */
|
|
|
|
for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1998-01-01 13:13:13 +00:00
|
|
|
if (*kp < 0x20 || (*kp > 0x7E && *kp < 0xA1))
|
1997-05-16 07:46:07 +00:00
|
|
|
{
|
|
|
|
char msg[40];
|
1997-01-17 07:34:35 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
sprintf(msg, "Invalid %s keyword character 0x%02X",
|
|
|
|
png_ptr->chunk_name, *kp);
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
*dp = ' ';
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
*dp = *kp;
|
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
*dp = '\0';
|
1997-01-17 07:34:35 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* Remove any trailing white space. */
|
|
|
|
kp = *new_key + key_len - 1;
|
|
|
|
if (*kp == ' ')
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
char msg[50];
|
|
|
|
sprintf(msg, "Trailing spaces removed from %s keyword",
|
|
|
|
png_ptr->chunk_name);
|
|
|
|
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
|
|
|
|
while (*kp == ' ')
|
|
|
|
{
|
|
|
|
*(kp--) = '\0';
|
|
|
|
key_len--;
|
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Remove any leading white space. */
|
1997-05-16 07:46:07 +00:00
|
|
|
kp = *new_key;
|
|
|
|
if (*kp == ' ')
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
char msg[50];
|
|
|
|
sprintf(msg, "Leading spaces removed from %s keyword",
|
|
|
|
png_ptr->chunk_name);
|
|
|
|
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
|
|
|
|
while (*kp == ' ')
|
|
|
|
{
|
|
|
|
kp++;
|
|
|
|
key_len--;
|
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug1(2, "Checking for multiple internal spaces in '%s'\n", kp);
|
|
|
|
|
|
|
|
/* Remove multiple internal spaces. */
|
|
|
|
for (kflag = 0, dp = *new_key; *kp != '\0'; kp++)
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
if (*kp == ' ' && kflag == 0)
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
*(dp++) = *kp;
|
|
|
|
kflag = 1;
|
1997-01-17 07:34:35 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
else if (*kp == ' ')
|
1997-01-17 07:34:35 +00:00
|
|
|
{
|
|
|
|
key_len--;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
*(dp++) = *kp;
|
|
|
|
kflag = 0;
|
1997-01-17 07:34:35 +00:00
|
|
|
}
|
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
*dp = '\0';
|
1997-01-17 07:34:35 +00:00
|
|
|
|
|
|
|
if (key_len == 0)
|
1997-05-16 07:46:07 +00:00
|
|
|
{
|
|
|
|
char msg[40];
|
|
|
|
|
|
|
|
sprintf(msg, "Zero length %s keyword", png_ptr->chunk_name);
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (key_len > 79)
|
|
|
|
{
|
|
|
|
char msg[50];
|
|
|
|
|
|
|
|
sprintf(msg, "%s keyword length must be 1 - 79 characters",
|
|
|
|
png_ptr->chunk_name);
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
new_key[79] = '\0';
|
|
|
|
key_len = 79;
|
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
|
|
|
|
return key_len;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_tEXt_SUPPORTED)
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write a tEXt chunk */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t text_len)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t key_len;
|
1998-01-01 13:13:13 +00:00
|
|
|
png_charp new_key;
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
png_debug(1, "in png_write_tEXt\n");
|
|
|
|
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
|
|
|
|
{
|
|
|
|
char msg[40];
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
sprintf(msg, "Empty keyword in %s chunk", "tEXt");
|
|
|
|
png_warning(png_ptr, msg);
|
1996-06-05 20:50:50 +00:00
|
|
|
return;
|
1997-05-16 07:46:07 +00:00
|
|
|
}
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
if (text == NULL || *text == '\0')
|
1997-01-17 07:34:35 +00:00
|
|
|
text_len = 0;
|
|
|
|
|
|
|
|
/* make sure we include the 0 after the key */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_start(png_ptr, png_tEXt, (png_uint_32)key_len+text_len+1);
|
1998-01-01 13:13:13 +00:00
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
|
1997-01-17 07:34:35 +00:00
|
|
|
if (text_len)
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
|
1997-01-17 07:34:35 +00:00
|
|
|
|
1995-07-20 07:43:20 +00:00
|
|
|
png_write_chunk_end(png_ptr);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_free(png_ptr, new_key);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_zTXt_SUPPORTED)
|
1997-05-16 07:46:07 +00:00
|
|
|
/* write a compressed text chunk */
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t text_len, int compression)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t key_len;
|
1995-07-20 07:43:20 +00:00
|
|
|
char buf[1];
|
1998-01-01 13:13:13 +00:00
|
|
|
png_charp new_key;
|
1995-07-20 07:43:20 +00:00
|
|
|
int i, ret;
|
1996-01-26 07:38:47 +00:00
|
|
|
png_charpp output_ptr = NULL; /* array of pointers to output */
|
1995-07-20 07:43:20 +00:00
|
|
|
int num_output_ptr = 0; /* number of output pointers used */
|
|
|
|
int max_output_ptr = 0; /* size of output_ptr */
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_zTXt\n");
|
|
|
|
|
|
|
|
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
|
|
|
|
{
|
|
|
|
char msg[40];
|
|
|
|
|
|
|
|
sprintf(msg, "Empty keyword in %s chunk", "zTXt");
|
|
|
|
png_warning(png_ptr, msg);
|
1996-06-05 20:50:50 +00:00
|
|
|
return;
|
1997-05-16 07:46:07 +00:00
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE)
|
|
|
|
{
|
|
|
|
png_write_tEXt(png_ptr, new_key, text, (png_size_t)0);
|
|
|
|
png_free(png_ptr, new_key);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
png_free(png_ptr, new_key);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
if (compression >= PNG_TEXT_COMPRESSION_LAST)
|
1996-06-05 20:50:50 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
char msg[50];
|
|
|
|
sprintf(msg, "Unknown zTXt compression type %d", compression);
|
|
|
|
png_warning(png_ptr, msg);
|
|
|
|
compression = PNG_TEXT_COMPRESSION_zTXt;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* We can't write the chunk until we find out how much data we have,
|
|
|
|
* which means we need to run the compressor first, and save the
|
|
|
|
* output. This shouldn't be a problem, as the vast majority of
|
|
|
|
* comments should be reasonable, but we will set up an array of
|
|
|
|
* malloc'd pointers to be sure.
|
|
|
|
*
|
|
|
|
* If we knew the application was well behaved, we could simplify this
|
|
|
|
* greatly by assuming we can always malloc an output buffer large
|
|
|
|
* enough to hold the compressed text ((1001 * text_len / 1000) + 12)
|
|
|
|
* and malloc this directly. The only time this would be a bad idea is
|
|
|
|
* if we can't malloc more than 64K and we have 64K of random input
|
|
|
|
* data, or if the input string is incredibly large (although this
|
|
|
|
* wouldn't cause a failure, just a slowdown due to swapping).
|
|
|
|
*/
|
1995-07-20 07:43:20 +00:00
|
|
|
|
|
|
|
/* set up the compression buffers */
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.avail_in = (uInt)text_len;
|
|
|
|
png_ptr->zstream.next_in = (Bytef *)text;
|
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
|
|
png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-01-26 07:38:47 +00:00
|
|
|
/* this is the same compression loop as in png_write_row() */
|
1995-07-20 07:43:20 +00:00
|
|
|
do
|
|
|
|
{
|
|
|
|
/* compress the data */
|
1997-01-17 07:34:35 +00:00
|
|
|
ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
|
1995-07-20 07:43:20 +00:00
|
|
|
if (ret != Z_OK)
|
|
|
|
{
|
|
|
|
/* error */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->zstream.msg != NULL)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
1995-07-20 07:43:20 +00:00
|
|
|
else
|
1995-12-19 09:22:19 +00:00
|
|
|
png_error(png_ptr, "zlib error");
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
/* check to see if we need more room */
|
1997-01-17 07:34:35 +00:00
|
|
|
if (!png_ptr->zstream.avail_out && png_ptr->zstream.avail_in)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
/* make sure the output array has room */
|
|
|
|
if (num_output_ptr >= max_output_ptr)
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
int old_max;
|
1995-09-26 10:22:39 +00:00
|
|
|
|
|
|
|
old_max = max_output_ptr;
|
1995-07-20 07:43:20 +00:00
|
|
|
max_output_ptr = num_output_ptr + 4;
|
1997-05-16 07:46:07 +00:00
|
|
|
if (output_ptr != NULL)
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
|
|
|
png_charpp old_ptr;
|
|
|
|
|
|
|
|
old_ptr = output_ptr;
|
1997-01-17 07:34:35 +00:00
|
|
|
output_ptr = (png_charpp)png_malloc(png_ptr,
|
1996-01-26 07:38:47 +00:00
|
|
|
max_output_ptr * sizeof (png_charpp));
|
1997-05-16 07:46:07 +00:00
|
|
|
png_memcpy(output_ptr, old_ptr, old_max * sizeof (png_charp));
|
1997-01-17 07:34:35 +00:00
|
|
|
png_free(png_ptr, old_ptr);
|
1996-01-26 07:38:47 +00:00
|
|
|
}
|
|
|
|
else
|
1997-01-17 07:34:35 +00:00
|
|
|
output_ptr = (png_charpp)png_malloc(png_ptr,
|
1996-01-26 07:38:47 +00:00
|
|
|
max_output_ptr * sizeof (png_charp));
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* save the data */
|
1997-05-16 07:46:07 +00:00
|
|
|
output_ptr[num_output_ptr] = png_malloc(png_ptr, png_ptr->zbuf_size);
|
1995-09-26 10:22:39 +00:00
|
|
|
png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->zbuf_size);
|
1995-07-20 07:43:20 +00:00
|
|
|
num_output_ptr++;
|
|
|
|
|
|
|
|
/* and reset the buffer */
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
/* continue until we don't have anymore to compress */
|
1997-01-17 07:34:35 +00:00
|
|
|
} while (png_ptr->zstream.avail_in);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-01-26 07:38:47 +00:00
|
|
|
/* finish the compression */
|
1995-07-20 07:43:20 +00:00
|
|
|
do
|
|
|
|
{
|
|
|
|
/* tell zlib we are finished */
|
1997-01-17 07:34:35 +00:00
|
|
|
ret = deflate(&png_ptr->zstream, Z_FINISH);
|
1995-07-20 07:43:20 +00:00
|
|
|
if (ret != Z_OK && ret != Z_STREAM_END)
|
|
|
|
{
|
|
|
|
/* we got an error */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->zstream.msg != NULL)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
1995-07-20 07:43:20 +00:00
|
|
|
else
|
1995-12-19 09:22:19 +00:00
|
|
|
png_error(png_ptr, "zlib error");
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* check to see if we need more room */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (!(png_ptr->zstream.avail_out) && ret == Z_OK)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1996-01-26 07:38:47 +00:00
|
|
|
/* check to make sure our output array has room */
|
|
|
|
if (num_output_ptr >= max_output_ptr)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
int old_max;
|
1995-09-26 10:22:39 +00:00
|
|
|
|
|
|
|
old_max = max_output_ptr;
|
1995-07-20 07:43:20 +00:00
|
|
|
max_output_ptr = num_output_ptr + 4;
|
1997-05-16 07:46:07 +00:00
|
|
|
if (output_ptr != NULL)
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
|
|
|
png_charpp old_ptr;
|
|
|
|
|
|
|
|
old_ptr = output_ptr;
|
1997-05-16 07:46:07 +00:00
|
|
|
/* This could be optimized to realloc() */
|
1997-01-17 07:34:35 +00:00
|
|
|
output_ptr = (png_charpp)png_malloc(png_ptr,
|
1996-01-26 07:38:47 +00:00
|
|
|
max_output_ptr * sizeof (png_charpp));
|
1997-05-16 07:46:07 +00:00
|
|
|
png_memcpy(output_ptr, old_ptr, old_max * sizeof (png_charp));
|
1997-01-17 07:34:35 +00:00
|
|
|
png_free(png_ptr, old_ptr);
|
1996-01-26 07:38:47 +00:00
|
|
|
}
|
|
|
|
else
|
1997-01-17 07:34:35 +00:00
|
|
|
output_ptr = (png_charpp)png_malloc(png_ptr,
|
1996-01-26 07:38:47 +00:00
|
|
|
max_output_ptr * sizeof (png_charp));
|
|
|
|
}
|
|
|
|
|
|
|
|
/* save off the data */
|
1997-01-17 07:34:35 +00:00
|
|
|
output_ptr[num_output_ptr] = png_malloc(png_ptr,
|
1996-01-26 07:38:47 +00:00
|
|
|
png_ptr->zbuf_size);
|
|
|
|
png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->zbuf_size);
|
1995-07-20 07:43:20 +00:00
|
|
|
num_output_ptr++;
|
|
|
|
|
|
|
|
/* and reset the buffer pointers */
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
} while (ret != Z_STREAM_END);
|
|
|
|
|
|
|
|
/* text length is number of buffers plus last buffer */
|
1996-01-26 07:38:47 +00:00
|
|
|
text_len = png_ptr->zbuf_size * num_output_ptr;
|
1997-01-17 07:34:35 +00:00
|
|
|
if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
|
1997-05-16 07:46:07 +00:00
|
|
|
text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
|
|
|
/* write start of chunk */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_start(png_ptr, png_zTXt, (png_uint_32)(key_len+text_len+2));
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write key */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1);
|
1996-01-26 07:38:47 +00:00
|
|
|
buf[0] = (png_byte)compression;
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write compression */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
|
|
|
/* write saved output buffers, if any */
|
|
|
|
for (i = 0; i < num_output_ptr; i++)
|
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk_data(png_ptr,(png_bytep)output_ptr[i],png_ptr->zbuf_size);
|
1997-01-17 07:34:35 +00:00
|
|
|
png_free(png_ptr, output_ptr[i]);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
if (max_output_ptr != 0)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_free(png_ptr, output_ptr);
|
1995-07-20 07:43:20 +00:00
|
|
|
/* write anything left in zbuf */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size)
|
1995-07-20 07:43:20 +00:00
|
|
|
png_write_chunk_data(png_ptr, png_ptr->zbuf,
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
|
1995-07-20 07:43:20 +00:00
|
|
|
/* close the chunk */
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
|
|
|
|
|
|
/* reset zlib for another zTXt or the image data */
|
1997-01-17 07:34:35 +00:00
|
|
|
deflateReset(&png_ptr->zstream);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_oFFs_SUPPORTED)
|
|
|
|
/* write the oFFs chunk */
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_oFFs(png_structp png_ptr, png_uint_32 x_offset,
|
|
|
|
png_uint_32 y_offset,
|
1995-07-20 07:43:20 +00:00
|
|
|
int unit_type)
|
|
|
|
{
|
|
|
|
png_byte buf[9];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_oFFs\n");
|
|
|
|
if (unit_type >= PNG_OFFSET_LAST)
|
|
|
|
png_warning(png_ptr, "Unrecognized unit type for oFFs chunk");
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_save_uint_32(buf, x_offset);
|
|
|
|
png_save_uint_32(buf + 4, y_offset);
|
1996-01-26 07:38:47 +00:00
|
|
|
buf[8] = (png_byte)unit_type;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
#if defined(PNG_WRITE_pCAL_SUPPORTED)
|
|
|
|
/* write the pCAL chunk (png-scivis-19970203) */
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
|
|
|
|
png_int_32 X1, int type, int nparams, png_charp units, png_charpp params)
|
|
|
|
{
|
|
|
|
png_size_t purpose_len, units_len, total_len;
|
|
|
|
png_uint_32p params_len;
|
|
|
|
png_byte buf[10];
|
1998-01-01 13:13:13 +00:00
|
|
|
png_charp new_purpose;
|
1997-05-16 07:46:07 +00:00
|
|
|
int i;
|
|
|
|
|
|
|
|
png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams);
|
|
|
|
if (type >= PNG_EQUATION_LAST)
|
|
|
|
png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
|
|
|
|
|
|
|
|
purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1;
|
|
|
|
png_debug1(3, "pCAL purpose length = %d\n", purpose_len);
|
|
|
|
units_len = png_strlen(units) + (nparams == 0 ? 0 : 1);
|
|
|
|
png_debug1(3, "pCAL units length = %d\n", units_len);
|
|
|
|
total_len = purpose_len + units_len + 10;
|
|
|
|
|
|
|
|
params_len = (png_uint_32p)png_malloc(png_ptr, nparams*sizeof(png_uint_32));
|
|
|
|
|
|
|
|
/* Find the length of each parameter, making sure we don't count the
|
|
|
|
null terminator for the last parameter. */
|
|
|
|
for (i = 0; i < nparams; i++)
|
|
|
|
{
|
|
|
|
params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1);
|
|
|
|
png_debug2(3, "pCAL parameter %d length = %d\n", i, params_len[i]);
|
|
|
|
total_len += (png_size_t)params_len[i];
|
|
|
|
}
|
|
|
|
|
|
|
|
png_debug1(3, "pCAL total length = %d\n", total_len);
|
|
|
|
png_write_chunk_start(png_ptr, png_pCAL, total_len);
|
1998-01-01 13:13:13 +00:00
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_save_int_32(buf, X0);
|
|
|
|
png_save_int_32(buf + 4, X1);
|
|
|
|
buf[8] = (png_byte)type;
|
|
|
|
buf[9] = (png_byte)nparams;
|
|
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)10);
|
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len);
|
|
|
|
|
|
|
|
png_free(png_ptr, new_purpose);
|
|
|
|
|
|
|
|
for (i = 0; i < nparams; i++)
|
|
|
|
{
|
|
|
|
png_write_chunk_data(png_ptr, (png_bytep)params[i],
|
|
|
|
(png_size_t)params_len[i]);
|
|
|
|
}
|
|
|
|
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_pHYs_SUPPORTED)
|
|
|
|
/* write the pHYs chunk */
|
|
|
|
void
|
|
|
|
png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
|
|
|
|
png_uint_32 y_pixels_per_unit,
|
1995-07-20 07:43:20 +00:00
|
|
|
int unit_type)
|
|
|
|
{
|
|
|
|
png_byte buf[9];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_pHYs\n");
|
|
|
|
if (unit_type >= PNG_RESOLUTION_LAST)
|
|
|
|
png_warning(png_ptr, "Unrecognized unit type for pHYs chunk");
|
1996-06-05 20:50:50 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_save_uint_32(buf, x_pixels_per_unit);
|
|
|
|
png_save_uint_32(buf + 4, y_pixels_per_unit);
|
1996-01-26 07:38:47 +00:00
|
|
|
buf[8] = (png_byte)unit_type;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_tIME_SUPPORTED)
|
1998-01-01 13:13:13 +00:00
|
|
|
/* Write the tIME chunk. Use either png_convert_from_struct_tm()
|
|
|
|
* or png_convert_from_time_t(), or fill in the structure yourself.
|
|
|
|
*/
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_tIME(png_structp png_ptr, png_timep mod_time)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_byte buf[7];
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_tIME\n");
|
1996-06-05 20:50:50 +00:00
|
|
|
if (mod_time->month > 12 || mod_time->month < 1 ||
|
|
|
|
mod_time->day > 31 || mod_time->day < 1 ||
|
|
|
|
mod_time->hour > 23 || mod_time->second > 60)
|
|
|
|
{
|
|
|
|
png_warning(png_ptr, "Invalid time specified for tIME chunk");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
1995-07-20 07:43:20 +00:00
|
|
|
png_save_uint_16(buf, mod_time->year);
|
|
|
|
buf[2] = mod_time->month;
|
|
|
|
buf[3] = mod_time->day;
|
|
|
|
buf[4] = mod_time->hour;
|
|
|
|
buf[5] = mod_time->minute;
|
|
|
|
buf[6] = mod_time->second;
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_write_chunk(png_ptr, png_tIME, buf, (png_size_t)7);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
|
|
|
/* initializes the row writing capability of libpng */
|
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_start_row(png_structp png_ptr)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t buf_size;
|
|
|
|
|
|
|
|
png_debug(1, "in png_write_start_row\n");
|
|
|
|
buf_size = (png_size_t)(((png_ptr->width * png_ptr->usr_channels *
|
|
|
|
png_ptr->usr_bit_depth + 7) >> 3) + 1);
|
|
|
|
|
1995-07-20 07:43:20 +00:00
|
|
|
/* set up row buffer */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, buf_size);
|
|
|
|
png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
/* set up filtering buffer, if using this filter */
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_SUB)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
|
1995-07-20 07:43:20 +00:00
|
|
|
png_ptr->rowbytes + 1);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* We only need to keep the previous row if we are using one of these. */
|
1996-06-05 20:50:50 +00:00
|
|
|
if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
|
|
|
|
{
|
|
|
|
/* set up previous row buffer */
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, buf_size);
|
|
|
|
png_memset(png_ptr->prev_row, 0, buf_size);
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_UP)
|
|
|
|
{
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->up_row = (png_bytep )png_malloc(png_ptr,
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->rowbytes + 1);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_AVG)
|
|
|
|
{
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->avg_row = (png_bytep )png_malloc(png_ptr,
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->rowbytes + 1);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_PAETH)
|
|
|
|
{
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
|
1996-06-05 20:50:50 +00:00
|
|
|
png_ptr->rowbytes + 1);
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* if interlaced, we need to set up width and height of pass */
|
1996-01-26 07:38:47 +00:00
|
|
|
if (png_ptr->interlaced)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
if (!(png_ptr->transformations & PNG_INTERLACE))
|
|
|
|
{
|
|
|
|
png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
|
|
|
|
png_pass_ystart[0]) / png_pass_yinc[0];
|
1997-05-16 07:46:07 +00:00
|
|
|
png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 -
|
|
|
|
png_pass_start[0]) / png_pass_inc[0];
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
png_ptr->num_rows = png_ptr->height;
|
|
|
|
png_ptr->usr_width = png_ptr->width;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
1995-07-20 07:43:20 +00:00
|
|
|
png_ptr->num_rows = png_ptr->height;
|
|
|
|
png_ptr->usr_width = png_ptr->width;
|
|
|
|
}
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* Internal use only. Called when finished processing a row of data. */
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_write_finish_row(png_structp png_ptr)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_finish_row\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
/* next row */
|
|
|
|
png_ptr->row_number++;
|
1996-06-17 21:24:45 +00:00
|
|
|
|
1995-07-20 07:43:20 +00:00
|
|
|
/* see if we are done */
|
1995-12-19 09:22:19 +00:00
|
|
|
if (png_ptr->row_number < png_ptr->num_rows)
|
1996-01-26 07:38:47 +00:00
|
|
|
return;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
|
|
|
/* if interlaced, go to next pass */
|
|
|
|
if (png_ptr->interlaced)
|
|
|
|
{
|
|
|
|
png_ptr->row_number = 0;
|
|
|
|
if (png_ptr->transformations & PNG_INTERLACE)
|
|
|
|
{
|
|
|
|
png_ptr->pass++;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
/* loop until we find a non-zero width or height pass */
|
|
|
|
do
|
|
|
|
{
|
|
|
|
png_ptr->pass++;
|
|
|
|
if (png_ptr->pass >= 7)
|
|
|
|
break;
|
1996-01-26 07:38:47 +00:00
|
|
|
png_ptr->usr_width = (png_ptr->width +
|
1995-07-20 07:43:20 +00:00
|
|
|
png_pass_inc[png_ptr->pass] - 1 -
|
|
|
|
png_pass_start[png_ptr->pass]) /
|
|
|
|
png_pass_inc[png_ptr->pass];
|
|
|
|
png_ptr->num_rows = (png_ptr->height +
|
|
|
|
png_pass_yinc[png_ptr->pass] - 1 -
|
|
|
|
png_pass_ystart[png_ptr->pass]) /
|
|
|
|
png_pass_yinc[png_ptr->pass];
|
1995-09-26 10:22:39 +00:00
|
|
|
if (png_ptr->transformations & PNG_INTERLACE)
|
|
|
|
break;
|
1995-07-20 07:43:20 +00:00
|
|
|
} while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
|
|
|
|
|
|
|
|
}
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* reset the row above the image for the next pass */
|
1996-01-26 07:38:47 +00:00
|
|
|
if (png_ptr->pass < 7)
|
1996-06-17 21:24:45 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->prev_row != NULL)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_memset(png_ptr->prev_row, 0,
|
|
|
|
(png_size_t) (((png_uint_32)png_ptr->usr_channels *
|
1996-06-17 21:24:45 +00:00
|
|
|
(png_uint_32)png_ptr->usr_bit_depth *
|
|
|
|
png_ptr->width + 7) >> 3) + 1);
|
1995-07-20 07:43:20 +00:00
|
|
|
return;
|
1996-06-17 21:24:45 +00:00
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* if we get here, we've just written the last row, so we need
|
|
|
|
to flush the compressor */
|
|
|
|
do
|
|
|
|
{
|
|
|
|
/* tell the compressor we are done */
|
1997-01-17 07:34:35 +00:00
|
|
|
ret = deflate(&png_ptr->zstream, Z_FINISH);
|
1995-07-20 07:43:20 +00:00
|
|
|
/* check for an error */
|
|
|
|
if (ret != Z_OK && ret != Z_STREAM_END)
|
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->zstream.msg != NULL)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
1995-07-20 07:43:20 +00:00
|
|
|
else
|
1995-12-19 09:22:19 +00:00
|
|
|
png_error(png_ptr, "zlib error");
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1996-01-26 07:38:47 +00:00
|
|
|
/* check to see if we need more room */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (!(png_ptr->zstream.avail_out) && ret == Z_OK)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
} while (ret != Z_STREAM_END);
|
|
|
|
|
|
|
|
/* write any extra space */
|
1997-01-17 07:34:35 +00:00
|
|
|
if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size -
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.avail_out);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
1997-01-17 07:34:35 +00:00
|
|
|
deflateReset(&png_ptr->zstream);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
|
1998-01-01 13:13:13 +00:00
|
|
|
/* Pick out the correct pixels for the interlace pass.
|
|
|
|
* The basic idea here is to go through the row with a source
|
|
|
|
* pointer and a destination pointer (sp and dp), and copy the
|
|
|
|
* correct pixels for the pass. As the row gets compacted,
|
|
|
|
* sp will always be >= dp, so we should never overwrite anything.
|
|
|
|
* See the default: case for the easiest code to understand.
|
|
|
|
*/
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1995-12-19 09:22:19 +00:00
|
|
|
png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_do_write_interlace\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
/* we don't have to do anything on the last pass (6) */
|
1997-05-16 07:46:07 +00:00
|
|
|
#if defined(PNG_USELESS_TESTS_SUPPORTED)
|
|
|
|
if (row != NULL && row_info != NULL && pass < 6)
|
|
|
|
#else
|
|
|
|
if (pass < 6)
|
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
|
|
|
/* each pixel depth is handled seperately */
|
|
|
|
switch (row_info->pixel_depth)
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
1995-07-20 07:43:20 +00:00
|
|
|
case 1:
|
|
|
|
{
|
1995-12-19 09:22:19 +00:00
|
|
|
png_bytep sp;
|
|
|
|
png_bytep dp;
|
1995-07-20 07:43:20 +00:00
|
|
|
int shift;
|
|
|
|
int d;
|
|
|
|
int value;
|
|
|
|
png_uint_32 i;
|
|
|
|
|
|
|
|
dp = row;
|
|
|
|
d = 0;
|
|
|
|
shift = 7;
|
1997-05-16 07:46:07 +00:00
|
|
|
for (i = png_pass_start[pass]; i < row_info->width;
|
1995-07-20 07:43:20 +00:00
|
|
|
i += png_pass_inc[pass])
|
|
|
|
{
|
|
|
|
sp = row + (png_size_t)(i >> 3);
|
1996-01-26 07:38:47 +00:00
|
|
|
value = (int)(*sp >> (7 - (int)(i & 7))) & 0x1;
|
1995-07-20 07:43:20 +00:00
|
|
|
d |= (value << shift);
|
|
|
|
|
|
|
|
if (shift == 0)
|
|
|
|
{
|
|
|
|
shift = 7;
|
1996-01-26 07:38:47 +00:00
|
|
|
*dp++ = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
d = 0;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
shift--;
|
|
|
|
|
|
|
|
}
|
|
|
|
if (shift != 7)
|
1996-01-26 07:38:47 +00:00
|
|
|
*dp = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
case 2:
|
1996-01-26 07:38:47 +00:00
|
|
|
{
|
1995-12-19 09:22:19 +00:00
|
|
|
png_bytep sp;
|
|
|
|
png_bytep dp;
|
1995-07-20 07:43:20 +00:00
|
|
|
int shift;
|
|
|
|
int d;
|
|
|
|
int value;
|
|
|
|
png_uint_32 i;
|
|
|
|
|
|
|
|
dp = row;
|
|
|
|
shift = 6;
|
|
|
|
d = 0;
|
1997-05-16 07:46:07 +00:00
|
|
|
for (i = png_pass_start[pass]; i < row_info->width;
|
1995-07-20 07:43:20 +00:00
|
|
|
i += png_pass_inc[pass])
|
|
|
|
{
|
|
|
|
sp = row + (png_size_t)(i >> 2);
|
|
|
|
value = (*sp >> ((3 - (int)(i & 3)) << 1)) & 0x3;
|
|
|
|
d |= (value << shift);
|
|
|
|
|
|
|
|
if (shift == 0)
|
|
|
|
{
|
|
|
|
shift = 6;
|
1996-01-26 07:38:47 +00:00
|
|
|
*dp++ = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
d = 0;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
shift -= 2;
|
|
|
|
}
|
|
|
|
if (shift != 6)
|
1996-01-26 07:38:47 +00:00
|
|
|
*dp = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
case 4:
|
|
|
|
{
|
1995-12-19 09:22:19 +00:00
|
|
|
png_bytep sp;
|
|
|
|
png_bytep dp;
|
1996-01-26 07:38:47 +00:00
|
|
|
int shift;
|
1995-07-20 07:43:20 +00:00
|
|
|
int d;
|
|
|
|
int value;
|
|
|
|
png_uint_32 i;
|
|
|
|
|
|
|
|
dp = row;
|
|
|
|
shift = 4;
|
|
|
|
d = 0;
|
1997-05-16 07:46:07 +00:00
|
|
|
for (i = png_pass_start[pass]; i < row_info->width;
|
1995-07-20 07:43:20 +00:00
|
|
|
i += png_pass_inc[pass])
|
|
|
|
{
|
|
|
|
sp = row + (png_size_t)(i >> 1);
|
|
|
|
value = (*sp >> ((1 - (int)(i & 1)) << 2)) & 0xf;
|
|
|
|
d |= (value << shift);
|
|
|
|
|
|
|
|
if (shift == 0)
|
|
|
|
{
|
1996-01-26 07:38:47 +00:00
|
|
|
shift = 4;
|
|
|
|
*dp++ = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
d = 0;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
shift -= 4;
|
|
|
|
}
|
|
|
|
if (shift != 4)
|
1996-01-26 07:38:47 +00:00
|
|
|
*dp = (png_byte)d;
|
1995-07-20 07:43:20 +00:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
default:
|
|
|
|
{
|
1995-12-19 09:22:19 +00:00
|
|
|
png_bytep sp;
|
|
|
|
png_bytep dp;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 i;
|
|
|
|
png_size_t pixel_bytes;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-01-26 07:38:47 +00:00
|
|
|
/* start at the beginning */
|
1995-07-20 07:43:20 +00:00
|
|
|
dp = row;
|
|
|
|
/* find out how many bytes each pixel takes up */
|
|
|
|
pixel_bytes = (row_info->pixel_depth >> 3);
|
|
|
|
/* loop through the row, only looking at the pixels that
|
|
|
|
matter */
|
1997-05-16 07:46:07 +00:00
|
|
|
for (i = png_pass_start[pass]; i < row_info->width;
|
1995-07-20 07:43:20 +00:00
|
|
|
i += png_pass_inc[pass])
|
|
|
|
{
|
|
|
|
/* find out where the original pixel is */
|
1997-05-16 07:46:07 +00:00
|
|
|
sp = row + i * pixel_bytes;
|
1995-07-20 07:43:20 +00:00
|
|
|
/* move the pixel */
|
|
|
|
if (dp != sp)
|
1995-09-26 10:22:39 +00:00
|
|
|
png_memcpy(dp, sp, pixel_bytes);
|
1995-07-20 07:43:20 +00:00
|
|
|
/* next pixel */
|
|
|
|
dp += pixel_bytes;
|
|
|
|
}
|
1996-01-26 07:38:47 +00:00
|
|
|
break;
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
/* set new row width */
|
|
|
|
row_info->width = (row_info->width +
|
|
|
|
png_pass_inc[pass] - 1 -
|
|
|
|
png_pass_start[pass]) /
|
|
|
|
png_pass_inc[pass];
|
|
|
|
row_info->rowbytes = ((row_info->width *
|
|
|
|
row_info->pixel_depth + 7) >> 3);
|
|
|
|
|
|
|
|
}
|
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* This filters the row, chooses which filter to use, if it has not already
|
|
|
|
* been specified by the application, and then writes the row out with the
|
1998-01-01 13:13:13 +00:00
|
|
|
* chosen filter.
|
|
|
|
*/
|
1997-05-16 07:46:07 +00:00
|
|
|
#define PNG_MAXSUM (~0x0UL >> 1)
|
|
|
|
#define PNG_HISHIFT 10
|
|
|
|
#define PNG_LOMASK 0xffffL
|
|
|
|
#define PNG_HIMASK (~PNG_LOMASK >> PNG_HISHIFT)
|
1995-07-20 07:43:20 +00:00
|
|
|
void
|
1996-06-05 20:50:50 +00:00
|
|
|
png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
png_bytep prev_row, best_row, row_buf;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 mins, bpp;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_find_filter\n");
|
1995-07-20 07:43:20 +00:00
|
|
|
/* find out how many bytes offset each pixel is */
|
|
|
|
bpp = (row_info->pixel_depth + 7) / 8;
|
1996-06-05 20:50:50 +00:00
|
|
|
|
|
|
|
prev_row = png_ptr->prev_row;
|
|
|
|
best_row = row_buf = png_ptr->row_buf;
|
1997-05-16 07:46:07 +00:00
|
|
|
mins = PNG_MAXSUM;
|
|
|
|
|
|
|
|
/* The prediction method we use is to find which method provides the
|
|
|
|
* smallest value when summing the absolute values of the distances
|
|
|
|
* from zero using anything >= 128 as negative numbers. This is known
|
|
|
|
* as the "minimum sum of absolute differences" heuristic. Other
|
|
|
|
* heruistics are the "weighted minumum sum of absolute differences"
|
|
|
|
* (experimental and can in theory improve compression), and the "zlib
|
|
|
|
* predictive" method (not implemented in libpng 0.95), which does test
|
|
|
|
* compressions of lines using different filter methods, and then chooses
|
|
|
|
* the (series of) filter(s) which give minimum compressed data size (VERY
|
|
|
|
* computationally expensive).
|
|
|
|
*/
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* We don't need to test the 'no filter' case if this is the only filter
|
1997-05-16 07:46:07 +00:00
|
|
|
* that has been chosen, as it doesn't actually do anything to the data.
|
|
|
|
*/
|
1996-06-05 20:50:50 +00:00
|
|
|
if (png_ptr->do_filter & PNG_FILTER_NONE &&
|
|
|
|
png_ptr->do_filter != PNG_FILTER_NONE)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
png_bytep rp;
|
|
|
|
png_uint_32 sum = 0;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_size_t i;
|
|
|
|
int v;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
for (i = 0, rp = row_buf + 1; i < row_info->rowbytes; i++, rp++)
|
|
|
|
{
|
|
|
|
v = *rp;
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 sumhi, sumlo;
|
|
|
|
sumlo = sum & PNG_LOMASK;
|
|
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
|
|
|
|
|
|
|
|
/* Reduce the sum if we match any of the previous rows */
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_NONE)
|
|
|
|
{
|
|
|
|
sumlo = (sumlo * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Factor in the cost of this filter (this is here for completeness,
|
|
|
|
* but it makes no sense to have a "cost" for the NONE filter, as
|
|
|
|
* it has the minimum possible computational cost - none).
|
|
|
|
*/
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
|
|
sum = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
|
|
}
|
|
|
|
#endif
|
1996-06-05 20:50:50 +00:00
|
|
|
mins = sum;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* sub filter */
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_SUB)
|
|
|
|
{
|
|
|
|
png_bytep rp, dp, lp;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
|
|
png_size_t i;
|
|
|
|
int v;
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
/* We temporarily increase the "minumum sum" by the factor we
|
|
|
|
* would reduce the sum of this filter, so that we can do the
|
|
|
|
* early exit comparison without scaling the sum each time.
|
|
|
|
*/
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 lmhi, lmlo;
|
|
|
|
lmlo = lmins & PNG_LOMASK;
|
|
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_SUB)
|
|
|
|
{
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
|
|
lmins = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
|
|
}
|
|
|
|
#endif
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
|
|
|
|
i++, rp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = *rp;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
}
|
|
|
|
for (lp = row_buf + 1; i < row_info->rowbytes; i++, rp++, lp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
|
|
|
|
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 sumhi, sumlo;
|
|
|
|
sumlo = sum & PNG_LOMASK;
|
|
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_SUB)
|
|
|
|
{
|
|
|
|
sumlo = (sumlo * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
|
|
sum = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
#endif
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sum < mins)
|
|
|
|
{
|
|
|
|
mins = sum;
|
|
|
|
best_row = png_ptr->sub_row;
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* up filter */
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_UP)
|
|
|
|
{
|
|
|
|
png_bytep rp, dp, pp;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
|
|
png_size_t i;
|
|
|
|
int v;
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 lmhi, lmlo;
|
|
|
|
lmlo = lmins & PNG_LOMASK;
|
|
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_UP)
|
|
|
|
{
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
|
|
lmins = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
|
|
}
|
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
|
|
|
|
pp = prev_row + 1; i < row_info->rowbytes; i++, rp++, pp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
|
|
|
|
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
|
|
break;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 sumhi, sumlo;
|
|
|
|
sumlo = sum & PNG_LOMASK;
|
|
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_UP)
|
|
|
|
{
|
|
|
|
sumlo = (sumlo * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
|
|
sum = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sum < mins)
|
|
|
|
{
|
|
|
|
mins = sum;
|
|
|
|
best_row = png_ptr->up_row;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* avg filter */
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_AVG)
|
1995-07-20 07:43:20 +00:00
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
png_bytep rp, dp, pp, lp;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
|
|
png_size_t i;
|
|
|
|
int v;
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 lmhi, lmlo;
|
|
|
|
lmlo = lmins & PNG_LOMASK;
|
|
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_AVG)
|
|
|
|
{
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
|
|
lmins = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
|
|
}
|
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
|
|
|
|
pp = prev_row + 1; i < bpp; i++, rp++, pp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = (png_byte)(((int)*rp - ((int)*pp / 2)) & 0xff);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
}
|
|
|
|
for (lp = row_buf + 1; i < row_info->rowbytes;
|
|
|
|
i++, rp++, pp++, lp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = (png_byte)(((int)*rp - (((int)*pp + (int)*lp) / 2)) & 0xff);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
sum += (v < 128) ? v : 256 - v;
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
|
|
break;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 sumhi, sumlo;
|
|
|
|
sumlo = sum & PNG_LOMASK;
|
|
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_NONE)
|
|
|
|
{
|
|
|
|
sumlo = (sumlo * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
|
|
sum = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sum < mins)
|
|
|
|
{
|
|
|
|
mins = sum;
|
|
|
|
best_row = png_ptr->avg_row;
|
|
|
|
}
|
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* Paeth filter */
|
1996-06-05 20:50:50 +00:00
|
|
|
if (png_ptr->do_filter & PNG_FILTER_PAETH)
|
|
|
|
{
|
|
|
|
png_bytep rp, dp, pp, cp, lp;
|
1997-05-16 07:46:07 +00:00
|
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
|
|
png_size_t i;
|
|
|
|
int v;
|
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 lmhi, lmlo;
|
|
|
|
lmlo = lmins & PNG_LOMASK;
|
|
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_PAETH)
|
|
|
|
{
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
|
|
lmins = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
|
|
}
|
|
|
|
#endif
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
|
|
|
|
pp = prev_row + 1; i < bpp; i++, rp++, pp++, dp++)
|
|
|
|
{
|
|
|
|
v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
}
|
|
|
|
for (lp = row_buf + 1, cp = prev_row + 1; i < row_info->rowbytes;
|
|
|
|
i++, rp++, pp++, lp++, dp++, cp++)
|
|
|
|
{
|
|
|
|
int a, b, c, pa, pb, pc, p;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
b = *pp;
|
|
|
|
c = *cp;
|
|
|
|
a = *lp;
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
p = a + b - c;
|
|
|
|
pa = abs(p - a);
|
|
|
|
pb = abs(p - b);
|
|
|
|
pc = abs(p - c);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
if (pa <= pb && pa <= pc)
|
|
|
|
p = a;
|
|
|
|
else if (pb <= pc)
|
|
|
|
p = b;
|
|
|
|
else
|
|
|
|
p = c;
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
v = *dp = (png_byte)(((int)*rp - p) & 0xff);
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
sum += (v < 128) ? v : 256 - v;
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
|
|
break;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
|
{
|
|
|
|
png_uint_32 sumhi, sumlo;
|
|
|
|
sumlo = sum & PNG_LOMASK;
|
|
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
|
|
|
|
for (i = 0; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
if (png_ptr->prev_filters[i] == PNG_FILTER_PAETH)
|
|
|
|
{
|
|
|
|
sumlo = (sumlo * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_weights[i]) >>
|
|
|
|
PNG_WEIGHT_SHIFT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
|
|
PNG_COST_SHIFT;
|
|
|
|
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
|
|
sum = PNG_MAXSUM;
|
|
|
|
else
|
|
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
if (sum < mins)
|
|
|
|
{
|
|
|
|
best_row = png_ptr->paeth_row;
|
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
}
|
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* Do the actual writing of the filtered row data from the chosen filter. */
|
1996-06-05 20:50:50 +00:00
|
|
|
png_write_filtered_row(png_ptr, best_row);
|
1997-05-16 07:46:07 +00:00
|
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
|
|
/* Save the type of filter we picked this time for future calculations */
|
|
|
|
if (png_ptr->num_prev_filters > 0)
|
|
|
|
{
|
|
|
|
png_byte i;
|
|
|
|
|
|
|
|
for (i = 1; i < png_ptr->num_prev_filters; i++)
|
|
|
|
{
|
|
|
|
png_ptr->prev_filters[i] = png_ptr->prev_filters[i - 1];
|
|
|
|
}
|
|
|
|
png_ptr->prev_filters[i] = best_row[0];
|
|
|
|
}
|
|
|
|
#endif
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1995-09-26 10:22:39 +00:00
|
|
|
|
1997-05-16 07:46:07 +00:00
|
|
|
/* Do the actual writing of a previously filtered row. */
|
1996-06-05 20:50:50 +00:00
|
|
|
void
|
|
|
|
png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
|
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
png_debug(1, "in png_write_filtered_row\n");
|
|
|
|
png_debug1(2, "filter = %d\n", filtered_row[0]);
|
1996-06-05 20:50:50 +00:00
|
|
|
/* set up the zlib input buffer */
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.next_in = filtered_row;
|
|
|
|
png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
|
1996-06-05 20:50:50 +00:00
|
|
|
/* repeat until we have compressed all the data */
|
|
|
|
do
|
1995-09-26 10:22:39 +00:00
|
|
|
{
|
1996-06-05 20:50:50 +00:00
|
|
|
int ret; /* return of zlib */
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* compress the data */
|
1997-01-17 07:34:35 +00:00
|
|
|
ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
|
1996-06-05 20:50:50 +00:00
|
|
|
/* check for compression errors */
|
|
|
|
if (ret != Z_OK)
|
|
|
|
{
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->zstream.msg != NULL)
|
1997-01-17 07:34:35 +00:00
|
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
1996-06-05 20:50:50 +00:00
|
|
|
else
|
|
|
|
png_error(png_ptr, "zlib error");
|
|
|
|
}
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* see if it is time to write another IDAT */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (!(png_ptr->zstream.avail_out))
|
1996-06-05 20:50:50 +00:00
|
|
|
{
|
|
|
|
/* write the IDAT and reset the zlib output buffer */
|
|
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
|
1997-01-17 07:34:35 +00:00
|
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
1996-06-05 20:50:50 +00:00
|
|
|
}
|
|
|
|
/* repeat until all data has been compressed */
|
1997-01-17 07:34:35 +00:00
|
|
|
} while (png_ptr->zstream.avail_in);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-17 21:24:45 +00:00
|
|
|
/* swap the current and previous rows */
|
1997-05-16 07:46:07 +00:00
|
|
|
if (png_ptr->prev_row != NULL)
|
1996-06-17 21:24:45 +00:00
|
|
|
{
|
|
|
|
png_bytep tptr;
|
|
|
|
|
|
|
|
tptr = png_ptr->prev_row;
|
|
|
|
png_ptr->prev_row = png_ptr->row_buf;
|
|
|
|
png_ptr->row_buf = tptr;
|
|
|
|
}
|
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
/* finish row - updates counters and flushes zlib if last row */
|
|
|
|
png_write_finish_row(png_ptr);
|
1995-07-20 07:43:20 +00:00
|
|
|
|
1996-06-05 20:50:50 +00:00
|
|
|
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
|
|
|
|
png_ptr->flush_rows++;
|
|
|
|
|
|
|
|
if (png_ptr->flush_dist > 0 &&
|
|
|
|
png_ptr->flush_rows >= png_ptr->flush_dist)
|
|
|
|
{
|
|
|
|
png_write_flush(png_ptr);
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1996-06-05 20:50:50 +00:00
|
|
|
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
|
1995-07-20 07:43:20 +00:00
|
|
|
}
|
1995-09-26 10:22:39 +00:00
|
|
|
|