libpng/contrib/libtests/makepng.c
John Bowler 59ae38984f [libpng16] Corrected simplified API default gamma for color-mapped output, added
a flag to change default. In 1.6.0 when the simplified API was used
to produce color-mapped output from an input image with no gamma
information the gamma assumed for the input could be different from
that assumed for non-color-mapped output.  In particular 16-bit depth
input files were assumed to be sRGB encoded, whereas in the 'direct'
case they were assumed to have linear data.  This was an error.  The
fix makes the simplified API treat all input files the same way and
adds a new flag to the png_image::flags member to allow the
application/user to specify that 16-bit files contain sRGB data
rather than the default linear.
Fixed bugs in the pngpixel and makepng test programs.
2013-03-06 22:15:25 -06:00

1487 lines
39 KiB
C

/* makepng.c
*
* Copyright (c) 2013 John Cunningham Bowler
*
* Last changed in libpng 1.6.1 [(PENDING RELEASE)]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*
* Make a test PNG image. The arguments are as follows:
*
* makepng [--sRGB|--linear|--1.8] [--color=<color>] color-type bit-depth \
* [file-name]
*
* The color-type may be numeric (and must match the numbers used by the PNG
* specification) or one of the format names listed below. The bit-depth is the
* component bit depth, or the pixel bit-depth for a color-mapped image.
*
* Without any options no color-space information is written, with the options
* an sRGB or the appropriate gAMA chunk is written. "1.8" refers to the
* display system used on older Apple computers to correct for high ambient
* light levels in the viewing environment; it applies a transform of
* approximately value^(1/1.45) to the color values and so a gAMA chunk of 65909
* is written (1.45/2.2).
*
* The image data is generated internally. Unless --color is given the images
* used are as follows:
*
* 1 channel: a square image with a diamond, the least luminous colors are on
* the edge of the image, the most luminous in the center.
*
* 2 channels: the color channel increases in luminosity from top to bottom, the
* alpha channel increases in opacity from left to right.
*
* 3 channels: linear combinations of, from the top-left corner clockwise,
* black, green, white, red.
*
* 4 channels: linear combinations of, from the top-left corner clockwise,
* transparent, red, green, blue.
*
* For color-mapped images a four channel color-map is used and the PNG file has
* a tRNS chunk, as follows:
*
* 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
* 2-bit: entry 0: transparent-green
* entry 1: 40%-red
* entry 2: 80%-blue
* entry 3: opaque-white
* 4-bit: the 16 combinations of the 2-bit case
* 8-bit: the 256 combinations of the 4-bit case
*
* The palette always has 2^bit-depth entries and the tRNS chunk one fewer. The
* image is the 1-channel diamond, but using palette index, not luminosity.
*
* Image size is determined by the final pixel depth in bits, i.e. channels x
* bit-depth, as follows:
*
* 8 bits or less: 64x64
* 16 bits: 256x256
* More than 16 bits: 1024x1024
*
* Row filtering is turned off (the 'none' filter is used on every row) and the
* images are not interlaced.
*
* If --color is given then the whole image has that color, color-mapped images
* will have exactly one palette entry and all image files with be 16x16 in
* size. The color value is 1 to 4 decimal numbers as appropriate for the color
* type.
*
* If file-name is given then the PNG is written to that file, else it is
* written to stdout. Notice that stdout is not supported on systems where, by
* default, it assumes text output; this program makes no attempt to change the
* text mode of stdout!
*/
#define _ISOC99_SOURCE /* for strtoull */
#include <stddef.h> /* for offsetof */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <errno.h>
#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
# include <config.h>
#endif
/* Define the following to use this test against your installed libpng, rather
* than the one being built here:
*/
#ifdef PNG_FREESTANDING_TESTS
# include <png.h>
#else
# include "../../png.h"
#endif
/* This structure is used for inserting extra chunks (the --insert argument, not
* documented above.)
*/
typedef struct chunk_insert
{
struct chunk_insert *next;
void (*insert)(png_structp, png_infop, int, png_charpp);
int nparams;
png_charp parameters[1];
} chunk_insert;
static int
channels_of_type(int color_type)
{
if (color_type & PNG_COLOR_MASK_PALETTE)
return 1;
else
{
int channels = 1;
if (color_type & PNG_COLOR_MASK_COLOR)
channels = 3;
if (color_type & PNG_COLOR_MASK_ALPHA)
return channels + 1;
else
return channels;
}
}
static int
pixel_depth_of_type(int color_type, int bit_depth)
{
return channels_of_type(color_type) * bit_depth;
}
static unsigned int
image_size_of_type(int color_type, int bit_depth, unsigned int *colors)
{
if (*colors)
return 16;
else
{
int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
if (pixel_depth < 8)
return 64;
else if (pixel_depth > 16)
return 1024;
else
return 256;
}
}
static void
set_color(png_colorp color, png_bytep trans, unsigned int red,
unsigned int green, unsigned int blue, unsigned int alpha,
png_const_bytep gamma_table)
{
color->red = gamma_table[red];
color->green = gamma_table[green];
color->blue = gamma_table[blue];
*trans = (png_byte)alpha;
}
static int
generate_palette(png_colorp palette, png_bytep trans, int bit_depth,
png_const_bytep gamma_table, unsigned int *colors)
{
/*
* 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
* 2-bit: entry 0: transparent-green
* entry 1: 40%-red
* entry 2: 80%-blue
* entry 3: opaque-white
* 4-bit: the 16 combinations of the 2-bit case
* 8-bit: the 256 combinations of the 4-bit case
*/
switch (colors[0])
{
default:
fprintf(stderr, "makepng: --colors=...: invalid count %u\n",
colors[0]);
exit(1);
case 1:
set_color(palette+0, trans+0, colors[1], colors[1], colors[1], 255,
gamma_table);
return 1;
case 2:
set_color(palette+0, trans+0, colors[1], colors[1], colors[1],
colors[2], gamma_table);
return 1;
case 3:
set_color(palette+0, trans+0, colors[1], colors[2], colors[3], 255,
gamma_table);
return 1;
case 4:
set_color(palette+0, trans+0, colors[1], colors[2], colors[3],
colors[4], gamma_table);
return 1;
case 0:
if (bit_depth == 1)
{
set_color(palette+0, trans+0, 255, 0, 0, 0, gamma_table);
set_color(palette+1, trans+1, 255, 255, 255, 255, gamma_table);
return 2;
}
else
{
unsigned int size = 1U << (bit_depth/2); /* 2, 4 or 16 */
unsigned int x, y, ip;
for (x=0; x<size; ++x) for (y=0; y<size; ++y)
{
ip = x + (size * y);
/* size is at most 16, so the scaled value below fits in 16 bits
*/
# define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
# define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
(interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
(size*size))
set_color(palette+ip, trans+ip,
/* color: green, red,blue,white */
xyinterp(x, y, 0, 255, 0, 255),
xyinterp(x, y, 255, 0, 0, 255),
xyinterp(x, y, 0, 0, 255, 255),
/* alpha: 0, 102, 204, 255) */
xyinterp(x, y, 0, 102, 204, 255),
gamma_table);
}
return ip+1;
}
}
}
static void
set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
png_uint_32 value, png_const_bytep gamma_table, double conv)
{
unsigned int mask = (1U << bit_depth)-1;
x *= bit_depth; /* Maximum x is 4*1024, maximum bit_depth is 16 */
if (value <= mask)
{
png_uint_32 offset = x >> 3;
if (offset < rowbytes && (bit_depth < 16 || offset+1 < rowbytes))
{
row += offset;
switch (bit_depth)
{
case 1:
case 2:
case 4:
/* Don't gamma correct - values get smashed */
{
unsigned int shift = (8 - bit_depth) - (x & 0x7U);
mask <<= shift;
value = (value << shift) & mask;
*row = (png_byte)((*row & ~mask) | value);
}
return;
default:
fprintf(stderr, "makepng: bad bit depth (internal error)\n");
exit(1);
case 16:
value = (unsigned int)floor(65535*pow(value/65535.,conv)+.5);
*row++ = (png_byte)(value >> 8);
*row = (png_byte)value;
return;
case 8:
*row = gamma_table[value];
return;
}
}
else
{
fprintf(stderr, "makepng: row buffer overflow (internal error)\n");
exit(1);
}
}
else
{
fprintf(stderr, "makepng: component overflow (internal error)\n");
exit(1);
}
}
static void
generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
int bit_depth, png_const_bytep gamma_table, double conv,
unsigned int *colors)
{
png_uint_32 size_max = image_size_of_type(color_type, bit_depth, colors)-1;
png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
if (colors[0] == 0) switch (channels_of_type(color_type))
{
/* 1 channel: a square image with a diamond, the least luminous colors are on
* the edge of the image, the most luminous in the center.
*/
case 1:
{
png_uint_32 x;
png_uint_32 base = 2*size_max - abs(2*y-size_max);
for (x=0; x<=size_max; ++x)
{
png_uint_32 luma = base - abs(2*x-size_max);
/* 'luma' is now in the range 0..2*size_max, we need
* 0..depth_max
*/
luma = (luma*depth_max + size_max) / (2*size_max);
set_value(row, rowbytes, x, bit_depth, luma, gamma_table, conv);
}
}
break;
/* 2 channels: the color channel increases in luminosity from top to bottom,
* the alpha channel increases in opacity from left to right.
*/
case 2:
{
png_uint_32 alpha = (depth_max * y * 2 + size_max) / (2 * size_max);
png_uint_32 x;
for (x=0; x<=size_max; ++x)
{
set_value(row, rowbytes, 2*x, bit_depth,
(depth_max * x * 2 + size_max) / (2 * size_max), gamma_table,
conv);
set_value(row, rowbytes, 2*x+1, bit_depth, alpha, gamma_table,
conv);
}
}
break;
/* 3 channels: linear combinations of, from the top-left corner clockwise,
* black, green, white, red.
*/
case 3:
{
/* x0: the black->red scale (the value of the red component) at the
* start of the row (blue and green are 0).
* x1: the green->white scale (the value of the red and blue
* components at the end of the row; green is depth_max).
*/
png_uint_32 Y = (depth_max * y * 2 + size_max) / (2 * size_max);
png_uint_32 x;
/* Interpolate x/depth_max from start to end:
*
* start end difference
* red: Y Y 0
* green: 0 depth_max depth_max
* blue: 0 Y Y
*/
for (x=0; x<=size_max; ++x)
{
set_value(row, rowbytes, 3*x+0, bit_depth, /* red */ Y,
gamma_table, conv);
set_value(row, rowbytes, 3*x+1, bit_depth, /* green */
(depth_max * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
set_value(row, rowbytes, 3*x+2, bit_depth, /* blue */
(Y * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
}
}
break;
/* 4 channels: linear combinations of, from the top-left corner clockwise,
* transparent, red, green, blue.
*/
case 4:
{
/* x0: the transparent->blue scale (the value of the blue and alpha
* components) at the start of the row (red and green are 0).
* x1: the red->green scale (the value of the red and green
* components at the end of the row; blue is 0 and alpha is
* depth_max).
*/
png_uint_32 Y = (depth_max * y * 2 + size_max) / (2 * size_max);
png_uint_32 x;
/* Interpolate x/depth_max from start to end:
*
* start end difference
* red: 0 depth_max-Y depth_max-Y
* green: 0 Y Y
* blue: Y 0 -Y
* alpha: Y depth_max depth_max-Y
*/
for (x=0; x<=size_max; ++x)
{
set_value(row, rowbytes, 4*x+0, bit_depth, /* red */
((depth_max-Y) * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
set_value(row, rowbytes, 4*x+1, bit_depth, /* green */
(Y * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
set_value(row, rowbytes, 4*x+2, bit_depth, /* blue */
Y - (Y * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
set_value(row, rowbytes, 4*x+3, bit_depth, /* alpha */
Y + ((depth_max-Y) * x * 2 + size_max) / (2 * size_max),
gamma_table, conv);
}
}
break;
default:
fprintf(stderr, "makepng: internal bad channel count\n");
exit(2);
}
else if (color_type & PNG_COLOR_MASK_PALETTE)
{
/* Palette with fixed color: the image rows are all 0 and the image width
* is 16.
*/
memset(row, 0, rowbytes);
}
else if (colors[0] == channels_of_type(color_type))
switch (channels_of_type(color_type))
{
case 1:
{
const png_uint_32 luma = colors[1];
png_uint_32 x;
for (x=0; x<=size_max; ++x)
set_value(row, rowbytes, x, bit_depth, luma, gamma_table,
conv);
}
break;
case 2:
{
const png_uint_32 luma = colors[1];
const png_uint_32 alpha = colors[2];
png_uint_32 x;
for (x=0; x<size_max; ++x)
{
set_value(row, rowbytes, 2*x, bit_depth, luma, gamma_table,
conv);
set_value(row, rowbytes, 2*x+1, bit_depth, alpha, gamma_table,
conv);
}
}
break;
case 3:
{
const png_uint_32 red = colors[1];
const png_uint_32 green = colors[2];
const png_uint_32 blue = colors[3];
png_uint_32 x;
for (x=0; x<=size_max; ++x)
{
set_value(row, rowbytes, 3*x+0, bit_depth, red, gamma_table,
conv);
set_value(row, rowbytes, 3*x+1, bit_depth, green, gamma_table,
conv);
set_value(row, rowbytes, 3*x+2, bit_depth, blue, gamma_table,
conv);
}
}
break;
case 4:
{
const png_uint_32 red = colors[1];
const png_uint_32 green = colors[2];
const png_uint_32 blue = colors[3];
const png_uint_32 alpha = colors[4];
png_uint_32 x;
for (x=0; x<=size_max; ++x)
{
set_value(row, rowbytes, 4*x+0, bit_depth, red, gamma_table,
conv);
set_value(row, rowbytes, 4*x+1, bit_depth, green, gamma_table,
conv);
set_value(row, rowbytes, 4*x+2, bit_depth, blue, gamma_table,
conv);
set_value(row, rowbytes, 4*x+3, bit_depth, alpha, gamma_table,
conv);
}
}
break;
default:
fprintf(stderr, "makepng: internal bad channel count\n");
exit(2);
}
else
{
fprintf(stderr,
"makepng: --color: count(%u) does not match channels(%u)\n",
colors[0], channels_of_type(color_type));
exit(1);
}
}
static void PNGCBAPI
makepng_warning(png_structp png_ptr, png_const_charp message)
{
const char **ep = png_get_error_ptr(png_ptr);
const char *name;
if (ep != NULL && *ep != NULL)
name = *ep;
else
name = "makepng";
fprintf(stderr, "%s: warning: %s\n", name, message);
}
static void PNGCBAPI
makepng_error(png_structp png_ptr, png_const_charp message)
{
makepng_warning(png_ptr, message);
png_longjmp(png_ptr, 1);
}
static int /* 0 on success, else an error code */
write_png(const char **name, FILE *fp, int color_type, int bit_depth,
volatile png_fixed_point gamma, chunk_insert * volatile insert,
unsigned int filters, unsigned int *colors)
{
png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
name, makepng_error, makepng_warning);
volatile png_infop info_ptr = NULL;
volatile png_bytep row = NULL;
if (png_ptr == NULL)
{
fprintf(stderr, "makepng: OOM allocating write structure\n");
return 1;
}
if (setjmp(png_jmpbuf(png_ptr)))
{
png_structp nv_ptr = png_ptr;
png_infop nv_info = info_ptr;
png_ptr = NULL;
info_ptr = NULL;
png_destroy_write_struct(&nv_ptr, &nv_info);
if (row != NULL) free(row);
return 1;
}
/* Allow benign errors so that we can write PNGs with errors */
png_set_benign_errors(png_ptr, 1/*allowed*/);
png_init_io(png_ptr, fp);
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
png_error(png_ptr, "OOM allocating info structure");
{
unsigned int size = image_size_of_type(color_type, bit_depth, colors);
png_fixed_point real_gamma = 45455; /* For sRGB */
png_byte gamma_table[256];
double conv;
/* This function uses the libpng values used on read to carry extra
* information about the gamma:
*/
if (gamma == PNG_GAMMA_MAC_18)
gamma = 65909;
else if (gamma > 0 && gamma < 1000)
gamma = PNG_FP_1;
if (gamma > 0)
real_gamma = gamma;
{
unsigned int i;
if (real_gamma == 45455) for (i=0; i<256; ++i)
{
gamma_table[i] = (png_byte)i;
conv = 1.;
}
else
{
/* Convert 'i' from sRGB (45455) to real_gamma, this makes
* the images look the same regardless of the gAMA chunk.
*/
conv = real_gamma;
conv /= 45455;
gamma_table[0] = 0;
for (i=1; i<255; ++i)
gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + .5);
gamma_table[255] = 255;
}
}
png_set_IHDR(png_ptr, info_ptr, size, size, bit_depth, color_type,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
if (color_type & PNG_COLOR_MASK_PALETTE)
{
int npalette;
png_color palette[256];
png_byte trans[256];
npalette = generate_palette(palette, trans, bit_depth, gamma_table,
colors);
png_set_PLTE(png_ptr, info_ptr, palette, npalette);
png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
NULL/*transparent color*/);
/* Reset gamma_table to prevent the image rows being changed */
for (npalette=0; npalette<256; ++npalette)
gamma_table[npalette] = (png_byte)npalette;
}
if (gamma == PNG_DEFAULT_sRGB)
png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_ABSOLUTE);
else if (gamma > 0) /* Else don't set color space information */
{
png_set_gAMA_fixed(png_ptr, info_ptr, real_gamma);
/* Just use the sRGB values here. */
png_set_cHRM_fixed(png_ptr, info_ptr,
/* color x y */
/* white */ 31270, 32900,
/* red */ 64000, 33000,
/* green */ 30000, 60000,
/* blue */ 15000, 6000
);
}
/* Insert extra information. */
while (insert != NULL)
{
insert->insert(png_ptr, info_ptr, insert->nparams, insert->parameters);
insert = insert->next;
}
/* Write the file header. */
png_write_info(png_ptr, info_ptr);
/* Restrict the filters */
png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, filters);
{
int passes = png_set_interlace_handling(png_ptr);
int pass;
png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
row = malloc(rowbytes);
if (row == NULL)
png_error(png_ptr, "OOM allocating row buffer");
for (pass = 0; pass < passes; ++pass)
{
unsigned int y;
for (y=0; y<size; ++y)
{
generate_row(row, rowbytes, y, color_type, bit_depth,
gamma_table, conv, colors);
png_write_row(png_ptr, row);
}
}
}
}
/* Finish writing the file. */
png_write_end(png_ptr, info_ptr);
{
png_structp nv_ptr = png_ptr;
png_infop nv_info = info_ptr;
png_ptr = NULL;
info_ptr = NULL;
png_destroy_write_struct(&nv_ptr, &nv_info);
}
free(row);
return 0;
}
static size_t
load_file(png_const_charp name, png_bytepp result)
{
FILE *fp = tmpfile();
if (fp != NULL)
{
FILE *ip = fopen(name, "rb");
if (ip != NULL)
{
size_t total = 0;
int ch;
for (;;)
{
ch = getc(ip);
if (ch == EOF) break;
putc(ch, fp);
++total;
}
if (ferror(ip))
{
perror(name);
fprintf(stderr, "%s: read error\n", name);
(void)fclose(ip);
}
else
{
(void)fclose(ip);
if (ferror(fp))
{
perror("temporary file");
fprintf(stderr, "temporary file write error\n");
}
else
{
rewind(fp);
if (total > 0)
{
/* Round up to a multiple of 4 here to allow an iCCP profile
* to be padded to a 4x boundary.
*/
png_bytep data = malloc((total+3)&~3);
if (data != NULL)
{
size_t new_size = 0;
for (;;)
{
ch = getc(fp);
if (ch == EOF) break;
data[new_size++] = (png_byte)ch;
}
if (ferror(fp) || new_size != total)
{
perror("temporary file");
fprintf(stderr, "temporary file read error\n");
free(data);
}
else
{
(void)fclose(fp);
*result = data;
return total;
}
}
else
fprintf(stderr, "%s: out of memory loading file\n", name);
}
else
fprintf(stderr, "%s: empty file\n", name);
}
}
}
else
{
perror(name);
fprintf(stderr, "%s: open failed\n", name);
}
fclose(fp);
}
else
fprintf(stderr, "makepng: %s: could not open temporary file\n", name);
exit(1);
return 0;
}
static png_size_t
load_fake(png_charp param, png_bytepp profile)
{
char *endptr = NULL;
unsigned long long int size = strtoull(param, &endptr, 0/*base*/);
/* The 'fake' format is <number>*[string] */
if (endptr != NULL && *endptr == '*')
{
size_t len = strlen(++endptr);
size_t result = (size_t)size;
if (len == 0) len = 1; /* capture the terminating '\0' */
/* Now repeat that string to fill 'size' bytes. */
if (result == size && (*profile = malloc(result)) != NULL)
{
png_bytep out = *profile;
if (len == 1)
memset(out, *endptr, result);
else
{
while (size >= len)
{
memcpy(out, endptr, len);
out += len;
size -= len;
}
memcpy(out, endptr, size);
}
return result;
}
else
{
fprintf(stderr, "%s: size exceeds system limits\n", param);
exit(1);
}
}
return 0;
}
static void
check_param_count(int nparams, int expect)
{
if (nparams != expect)
{
fprintf(stderr, "bad parameter count (internal error)\n");
exit(1);
}
}
static void
insert_iCCP(png_structp png_ptr, png_infop info_ptr, int nparams,
png_charpp params)
{
png_bytep profile = NULL;
png_uint_32 proflen = 0;
int result;
check_param_count(nparams, 2);
switch (params[1][0])
{
case '<':
{
png_size_t filelen = load_file(params[1]+1, &profile);
if (filelen > 0xfffffffc) /* Maximum profile length */
{
fprintf(stderr, "%s: file too long (%lu) for an ICC profile\n",
params[1]+1, (unsigned long)filelen);
exit(1);
}
proflen = (png_uint_32)filelen;
}
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
{
png_size_t fake_len = load_fake(params[1], &profile);
if (fake_len > 0) /* else a simple parameter */
{
if (fake_len > 0xffffffff) /* Maximum profile length */
{
fprintf(stderr,
"%s: fake data too long (%lu) for an ICC profile\n",
params[1], (unsigned long)fake_len);
exit(1);
}
proflen = (png_uint_32)(fake_len & ~3U);
/* Always fix up the profile length. */
png_save_uint_32(profile, proflen);
break;
}
}
default:
fprintf(stderr, "--insert iCCP \"%s\": unrecognized\n", params[1]);
fprintf(stderr, " use '<' to read a file: \"<filename\"\n");
exit(1);
}
result = 1;
if (proflen & 3)
{
fprintf(stderr,
"makepng: --insert iCCP %s: profile length made a multiple of 4\n",
params[1]);
/* load_file allocates extra space for this padding, the ICC spec requires
* padding with zero bytes.
*/
while (proflen & 3)
profile[proflen++] = 0;
}
if (profile != NULL && proflen > 3)
{
png_uint_32 prof_header = png_get_uint_32(profile);
if (prof_header != proflen)
{
fprintf(stderr, "--insert iCCP %s: profile length field wrong:\n",
params[1]);
fprintf(stderr, " actual %lu, recorded value %lu (corrected)\n",
(unsigned long)proflen, (unsigned long)prof_header);
png_save_uint_32(profile, proflen);
}
}
if (result && profile != NULL && proflen >=4)
png_set_iCCP(png_ptr, info_ptr, params[0], PNG_COMPRESSION_TYPE_BASE,
profile, proflen);
if (profile)
free(profile);
if (!result)
exit(1);
}
static void
clear_text(png_text *text, png_charp keyword)
{
text->compression = -1; /* none */
text->key = keyword;
text->text = NULL;
text->text_length = 0; /* libpng calculates this */
text->itxt_length = 0; /* libpng calculates this */
text->lang = NULL;
text->lang_key = NULL;
}
static void
set_text(png_structp png_ptr, png_infop info_ptr, png_textp text,
png_charp param)
{
switch (param[0])
{
case '<':
{
png_bytep file = NULL;
text->text_length = load_file(param+1, &file);
text->text = (png_charp)file;
}
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
{
png_bytep data = NULL;
png_size_t fake_len = load_fake(param, &data);
if (fake_len > 0) /* else a simple parameter */
{
text->text_length = fake_len;
text->text = (png_charp)data;
break;
}
}
default:
text->text = param;
break;
}
png_set_text(png_ptr, info_ptr, text, 1);
if (text->text != param)
free(text->text);
}
static void
insert_tEXt(png_structp png_ptr, png_infop info_ptr, int nparams,
png_charpp params)
{
png_text text;
check_param_count(nparams, 2);
clear_text(&text, params[0]);
set_text(png_ptr, info_ptr, &text, params[1]);
}
static void
insert_zTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
png_charpp params)
{
png_text text;
check_param_count(nparams, 2);
clear_text(&text, params[0]);
text.compression = 0; /* deflate */
set_text(png_ptr, info_ptr, &text, params[1]);
}
static void
insert_iTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
png_charpp params)
{
png_text text;
check_param_count(nparams, 4);
clear_text(&text, params[0]);
text.compression = 2; /* iTXt + deflate */
text.lang = params[1];/* language tag */
text.lang_key = params[2]; /* translated keyword */
set_text(png_ptr, info_ptr, &text, params[3]);
}
static void
insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
{
int i;
png_uint_16 freq[256];
/* libpng takes the count from the PLTE count; we don't check it here but we
* do set the array to 0 for unspecified entries.
*/
memset(freq, 0, sizeof freq);
for (i=0; i<nparams; ++i)
{
char *endptr = NULL;
unsigned long int l = strtoul(params[i], &endptr, 0/*base*/);
if (params[i][0] && *endptr == 0 && l <= 65535)
freq[i] = (png_uint_16)l;
else
{
fprintf(stderr, "hIST[%d]: %s: invalid frequency\n", i, params[i]);
exit(1);
}
}
png_set_hIST(png_ptr, info_ptr, freq);
}
#if 0
static void
insert_sPLT(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
{
fprintf(stderr, "insert sPLT: NYI\n");
}
#endif
static int
find_parameters(png_const_charp what, png_charp param, png_charp *list,
int nparams)
{
/* Parameters are separated by '\n' or ':' characters, up to nparams are
* accepted (more is an error) and the number found is returned.
*/
int i;
for (i=0; *param && i<nparams; ++i)
{
list[i] = param;
while (*++param) if (*param == '\n' || *param == ':')
{
*param++ = 0; /* Terminate last parameter */
break; /* And start a new one. */
}
}
if (*param)
{
fprintf(stderr, "--insert %s: too many parameters (%s)\n", what, param);
exit(1);
}
list[i] = NULL; /* terminates list */
return i; /* number of parameters filled in */
}
static void
bad_parameter_count(png_const_charp what, int nparams)
{
fprintf(stderr, "--insert %s: bad parameter count %d\n", what, nparams);
exit(1);
}
static chunk_insert *
make_insert(png_const_charp what,
void (*insert)(png_structp, png_infop, int, png_charpp),
int nparams, png_charpp list)
{
int i;
chunk_insert *cip;
cip = malloc(offsetof(chunk_insert,parameters) +
nparams * sizeof (png_charp));
if (cip == NULL)
{
fprintf(stderr, "--insert %s: out of memory allocating %d parameters\n",
what, nparams);
exit(1);
}
cip->next = NULL;
cip->insert = insert;
cip->nparams = nparams;
for (i=0; i<nparams; ++i)
cip->parameters[i] = list[i];
return cip;
}
static chunk_insert *
find_insert(png_const_charp what, png_charp param)
{
png_uint_32 chunk = 0;
png_charp parameter_list[1024];
int i, nparams;
/* Assemble the chunk name */
for (i=0; i<4; ++i)
{
char ch = what[i];
if ((ch >= 65 && ch <= 90) || (ch >= 97 && ch <= 122))
chunk = (chunk << 8) + what[i];
else
break;
}
if (i < 4 || what[4] != 0)
{
fprintf(stderr, "makepng --insert \"%s\": invalid chunk name\n", what);
exit(1);
}
/* Assemble the parameter list. */
nparams = find_parameters(what, param, parameter_list, 1024);
# define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))
switch (chunk)
{
case CHUNK(105,67,67,80): /* iCCP */
if (nparams == 2)
return make_insert(what, insert_iCCP, nparams, parameter_list);
break;
case CHUNK(116,69,88,116): /* tEXt */
if (nparams == 2)
return make_insert(what, insert_tEXt, nparams, parameter_list);
break;
case CHUNK(122,84,88,116): /* zTXt */
if (nparams == 2)
return make_insert(what, insert_zTXt, nparams, parameter_list);
break;
case CHUNK(105,84,88,116): /* iTXt */
if (nparams == 4)
return make_insert(what, insert_iTXt, nparams, parameter_list);
break;
case CHUNK(104,73,83,84): /* hIST */
if (nparams <= 256)
return make_insert(what, insert_hIST, nparams, parameter_list);
break;
#if 0
case CHUNK(115,80,76,84): /* sPLT */
return make_insert(what, insert_sPLT, nparams, parameter_list);
#endif
default:
fprintf(stderr, "makepng --insert \"%s\": unrecognized chunk name\n",
what);
exit(1);
}
bad_parameter_count(what, nparams);
return NULL;
}
/* This is a not-very-good parser for a sequence of numbers (including 0). It
* doesn't accept some apparently valid things, but it accepts all the sensible
* combinations.
*/
static void
parse_color(char *arg, unsigned int *colors)
{
unsigned int ncolors = 0;
while (*arg && ncolors < 4)
{
char *ep = arg;
unsigned long ul = strtoul(arg, &ep, 0);
if (ul > 65535)
{
fprintf(stderr, "makepng --color=...'%s': too big\n", arg);
exit(1);
}
if (ep == arg)
{
fprintf(stderr, "makepng --color=...'%s': not a valid color\n", arg);
exit(1);
}
if (*ep) ++ep; /* skip a separator */
arg = ep;
colors[++ncolors] = (unsigned int)ul; /* checked above */
}
if (*arg)
{
fprintf(stderr, "makepng --color=...'%s': too many values\n", arg);
exit(1);
}
*colors = ncolors;
}
int
main(int argc, char **argv)
{
FILE *fp = stdout;
const char *file_name = NULL;
int color_type = 8; /* invalid */
int bit_depth = 32; /* invalid */
unsigned int colors[5];
unsigned int filters = PNG_ALL_FILTERS;
png_fixed_point gamma = 0; /* not set */
chunk_insert *head_insert = NULL;
chunk_insert **insert_ptr = &head_insert;
memset(colors, 0, sizeof colors);
while (--argc > 0)
{
char *arg = *++argv;
if (strcmp(arg, "--sRGB") == 0)
{
gamma = PNG_DEFAULT_sRGB;
continue;
}
if (strcmp(arg, "--linear") == 0)
{
gamma = PNG_FP_1;
continue;
}
if (strcmp(arg, "--1.8") == 0)
{
gamma = PNG_GAMMA_MAC_18;
continue;
}
if (strcmp(arg, "--nofilters") == 0)
{
filters = PNG_FILTER_NONE;
continue;
}
if (strncmp(arg, "--color=", 8) == 0)
{
parse_color(arg+8, colors);
continue;
}
if (argc >= 3 && strcmp(arg, "--insert") == 0)
{
png_const_charp what = *++argv;
png_charp param = *++argv;
chunk_insert *new_insert;
argc -= 2;
new_insert = find_insert(what, param);
if (new_insert != NULL)
{
*insert_ptr = new_insert;
insert_ptr = &new_insert->next;
}
continue;
}
if (arg[0] == '-')
{
fprintf(stderr, "makepng: %s: invalid option\n", arg);
exit(1);
}
if (strcmp(arg, "palette") == 0)
{
color_type = PNG_COLOR_TYPE_PALETTE;
continue;
}
if (strncmp(arg, "gray", 4) == 0)
{
if (arg[4] == 0)
{
color_type = PNG_COLOR_TYPE_GRAY;
continue;
}
else if (strcmp(arg+4, "a") == 0 ||
strcmp(arg+4, "alpha") == 0 ||
strcmp(arg+4, "-alpha") == 0)
{
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
continue;
}
}
if (strncmp(arg, "rgb", 3) == 0)
{
if (arg[3] == 0)
{
color_type = PNG_COLOR_TYPE_RGB;
continue;
}
else if (strcmp(arg+3, "a") == 0 ||
strcmp(arg+3, "alpha") == 0 ||
strcmp(arg+3, "-alpha") == 0)
{
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
continue;
}
}
if (color_type == 8 && isdigit(arg[0]))
{
color_type = atoi(arg);
if (color_type < 0 || color_type > 6 || color_type == 1 ||
color_type == 5)
{
fprintf(stderr, "makepng: %s: not a valid color type\n", arg);
exit(1);
}
continue;
}
if (bit_depth == 32 && isdigit(arg[0]))
{
bit_depth = atoi(arg);
if (bit_depth <= 0 || bit_depth > 16 ||
(bit_depth & -bit_depth) != bit_depth)
{
fprintf(stderr, "makepng: %s: not a valid bit depth\n", arg);
exit(1);
}
continue;
}
if (argc == 1) /* It's the file name */
{
fp = fopen(arg, "wb");
if (fp == NULL)
{
fprintf(stderr, "%s: %s: could not open\n", arg, strerror(errno));
exit(1);
}
file_name = arg;
continue;
}
fprintf(stderr, "makepng: %s: unknown argument\n", arg);
exit(1);
} /* argument while loop */
if (color_type == 8 || bit_depth == 32)
{
fprintf(stderr, "usage: makepng [--sRGB|--linear|--1.8] "
"[--color=...] color-type bit-depth [file-name]\n"
" Make a test PNG file, by default writes to stdout.\n");
exit(1);
}
/* Check the colors */
{
const unsigned int lim = (color_type == PNG_COLOR_TYPE_PALETTE ? 255U :
(1U<<bit_depth)-1);
unsigned int i;
for (i=1; i<=colors[0]; ++i)
if (colors[i] > lim)
{
fprintf(stderr, "makepng: --color=...: %u out of range [0..%u]\n",
colors[i], lim);
exit(1);
}
}
/* Restrict the filters for more speed to those we know are used for the
* generated images.
*/
if (filters == PNG_ALL_FILTERS)
{
if ((color_type & PNG_COLOR_MASK_PALETTE) != 0 || bit_depth < 8)
filters = PNG_FILTER_NONE;
else if (color_type & PNG_COLOR_MASK_COLOR) /* rgb */
{
if (bit_depth == 8)
filters &= ~(PNG_FILTER_NONE | PNG_FILTER_AVG);
else
filters = PNG_FILTER_SUB | PNG_FILTER_PAETH;
}
else /* gray 8 or 16-bit */
filters &= ~PNG_FILTER_NONE;
}
{
int ret = write_png(&file_name, fp, color_type, bit_depth, gamma,
head_insert, filters, colors);
if (ret != 0 && file_name != NULL)
remove(file_name);
return ret;
}
}