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Imported from libpng-0.97.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-01-01 07:13:13 -06:00
parent 47a0c422ca
commit b6ce43d6ff
24 changed files with 1297 additions and 763 deletions
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128
pngwutil.c
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@@ -1,12 +1,12 @@
/* pngwutil.c - utilities to write a PNG file
libpng 1.0 beta 6 - version 0.96
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
Copyright (c) 1996, 1997 Andreas Dilger
May 12, 1997
*/
*
* libpng 1.00.97
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
* Copyright (c) 1996, 1997 Andreas Dilger
* May 28, 1997
*/
#define PNG_INTERNAL
#include "png.h"
@@ -26,8 +26,9 @@ png_save_uint_32(png_bytep buf, png_uint_32 i)
#if defined(PNG_WRITE_pCAL_SUPPORTED)
/* The png_save_int_32 function assumes integers are stored in two's
complement format. If this isn't the case, then this routine needs to
be modified to write data in two's complement format. */
* complement format. If this isn't the case, then this routine needs to
* be modified to write data in two's complement format.
*/
void
png_save_int_32(png_bytep buf, png_int_32 i)
{
@@ -38,22 +39,26 @@ png_save_int_32(png_bytep buf, png_int_32 i)
}
#endif
/* Place a 16-bit number into a buffer in PNG byte order. */
/* Place a 16-bit number into a buffer in PNG byte order.
* The parameter is declared unsigned int, not png_uint_16,
* just to avoid potential problems on pre-ANSI C compilers.
*/
void
png_save_uint_16(png_bytep buf, png_uint_16 i)
png_save_uint_16(png_bytep buf, unsigned int i)
{
buf[0] = (png_byte)((i >> 8) & 0xff);
buf[1] = (png_byte)(i & 0xff);
}
/* Write a PNG chunk all at once. The type is an array of ASCII characters
representing the chunk name. The array must be at least 4 bytes in
length, and does not need to be null terminated. To be safe, pass the
pre-defined chunk names here, and if you need a new one, define it
where the others are defined. The length is the length of the data.
All the data must be present. If that is not possible, use the
png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
functions instead. */
* representing the chunk name. The array must be at least 4 bytes in
* length, and does not need to be null terminated. To be safe, pass the
* pre-defined chunk names here, and if you need a new one, define it
* where the others are defined. The length is the length of the data.
* All the data must be present. If that is not possible, use the
* png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
* functions instead.
*/
void
png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
png_bytep data, png_size_t length)
@@ -64,8 +69,9 @@ png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
}
/* Write the start of a PNG chunk. The type is the chunk type.
The total_length is the sum of the lengths of all the data you will be
passing in png_write_chunk_data() */
* The total_length is the sum of the lengths of all the data you will be
* passing in png_write_chunk_data().
*/
void
png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
png_uint_32 length)
@@ -85,9 +91,10 @@ png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
}
/* Write the data of a PNG chunk started with png_write_chunk_start().
Note that multiple calls to this function are allowed, and that the
sum of the lengths from these calls *must* add up to the total_length
given to png_write_chunk_start(). */
* Note that multiple calls to this function are allowed, and that the
* sum of the lengths from these calls *must* add up to the total_length
* given to png_write_chunk_start().
*/
void
png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
@@ -106,11 +113,7 @@ png_write_chunk_end(png_structp png_ptr)
png_byte buf[4];
/* write the crc */
#ifdef PNG_USE_OWN_CRC
png_save_uint_32(buf, ~png_ptr->crc);
#else
png_save_uint_32(buf, png_ptr->crc);
#endif
png_write_data(png_ptr, buf, (png_size_t)4);
}
@@ -119,7 +122,8 @@ png_write_chunk_end(png_structp png_ptr)
* the magic bytes of the signature, or more likely, the PNG stream is
* being embedded into another stream and doesn't need its own signature,
* we should call png_set_sig_bytes() to tell libpng how many of the
* bytes have already been written. */
* bytes have already been written.
*/
void
png_write_sig(png_structp png_ptr)
{
@@ -129,8 +133,9 @@ png_write_sig(png_structp png_ptr)
}
/* Write the IHDR chunk, and update the png_struct with the necessary
information. Note that the rest of this code depends upon this
information being correct. */
* information. Note that the rest of this code depends upon this
* information being correct.
*/
void
png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
int bit_depth, int color_type, int compression_type, int filter_type,
@@ -264,8 +269,9 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
}
/* write the palette. We are careful not to trust png_color to be in the
correct order for PNG, so people can redefine it to any convient
structure. */
* correct order for PNG, so people can redefine it to any convient
* structure.
*/
void
png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
{
@@ -336,6 +342,22 @@ png_write_gAMA(png_structp png_ptr, double file_gamma)
}
#endif
#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
#if defined(PNG_WRITE_sBIT_SUPPORTED)
/* write the sBIT chunk */
void
@@ -560,11 +582,10 @@ png_write_hIST(png_structp png_ptr, png_uint_16p hist, png_uint_32 num_hist)
* static keywords without having to have duplicate copies of the strings.
*/
png_size_t
png_check_keyword(png_structp png_ptr, png_charp key, png_bytepp new_key)
png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
{
png_size_t key_len;
png_charp kp;
png_bytep dp;
png_charp kp, dp;
int kflag;
png_debug(1, "in png_check_keyword\n");
@@ -581,12 +602,12 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_bytepp new_key)
png_debug1(2, "Keyword to be checked is '%s'\n", key);
*new_key = (png_bytep)png_malloc(png_ptr, key_len + 1);
*new_key = (png_charp)png_malloc(png_ptr, key_len + 1);
/* Replace non-printing characters with a blank and print a warning */
for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
{
if (*kp < 0x20 || ((png_byte)*kp > 0x7E && (png_byte)*kp < 0xA1))
if (*kp < 0x20 || (*kp > 0x7E && *kp < 0xA1))
{
char msg[40];
@@ -688,7 +709,7 @@ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
png_size_t text_len)
{
png_size_t key_len;
png_bytep new_key;
png_charp new_key;
png_debug(1, "in png_write_tEXt\n");
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
@@ -705,7 +726,7 @@ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
/* make sure we include the 0 after the key */
png_write_chunk_start(png_ptr, png_tEXt, (png_uint_32)key_len+text_len+1);
png_write_chunk_data(png_ptr, new_key, key_len + 1);
png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
if (text_len)
png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
@@ -722,7 +743,7 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
{
png_size_t key_len;
char buf[1];
png_bytep new_key;
png_charp new_key;
int i, ret;
png_charpp output_ptr = NULL; /* array of pointers to output */
int num_output_ptr = 0; /* number of output pointers used */
@@ -945,7 +966,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
png_size_t purpose_len, units_len, total_len;
png_uint_32p params_len;
png_byte buf[10];
png_bytep new_purpose;
png_charp new_purpose;
int i;
png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams);
@@ -971,7 +992,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
png_debug1(3, "pCAL total length = %d\n", total_len);
png_write_chunk_start(png_ptr, png_pCAL, total_len);
png_write_chunk_data(png_ptr, new_purpose, purpose_len);
png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
png_save_int_32(buf, X0);
png_save_int_32(buf + 4, X1);
buf[8] = (png_byte)type;
@@ -1013,8 +1034,9 @@ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
/* write the tIME chunk. Use either png_convert_from_struct_tm()
or png_convert_from_time_t(), or fill in the structure yourself */
/* Write the tIME chunk. Use either png_convert_from_struct_tm()
* or png_convert_from_time_t(), or fill in the structure yourself.
*/
void
png_write_tIME(png_structp png_ptr, png_timep mod_time)
{
@@ -1206,14 +1228,13 @@ png_write_finish_row(png_structp png_ptr)
}
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* 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.
*/
/* 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.
*/
void
png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
{
@@ -1366,7 +1387,8 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
/* 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
* chosen filter. */
* chosen filter.
*/
#define PNG_MAXSUM (~0x0UL >> 1)
#define PNG_HISHIFT 10
#define PNG_LOMASK 0xffffL