libpng/contrib/libtests/makepng.c
John Bowler cb129a6234 [libpng16] Improved pngstest fine tuning of error numbers, new test file
generator.  The generator generates images that test the full range of sample
values, allow the error numbers in pngstest to be tuned and checked.  makepng
also allows generation of images with extra chunks, although this is
still work-in-progress.
2012-03-01 21:26:54 -06:00

1158 lines
31 KiB
C

/* makepng.c
*
* Copyright (c) 2012 John Cunningham Bowler
*
* Last changed in libpng 1.6.0 [(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-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. 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 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 <stdlib.h>
#include <stdio.h>
#include <string.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)
{
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)
{
/*
* 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
*/
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; /* Maxium x is 4*1024, maxium 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)
{
png_uint_32 size_max = image_size_of_type(color_type, bit_depth)-1;
png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
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);
}
}
static int /* 0 on success, else an error code */
write_png(FILE *fp, int color_type, int bit_depth,
volatile png_fixed_point gamma, chunk_insert * volatile insert)
{
png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,0,0,0);
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;
}
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);
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=0; i<255; ++i)
gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + 127.5);
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);
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, PNG_NO_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);
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)
{
png_bytep data = malloc(total);
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 > 0xffffffff) /* 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;
}
}
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,
"--insert iCCP %s: profile length must be a multiple of 4\n",
params[1]);
result = 0; /* Cannot fix this! */
}
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 (correted)\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;
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[2];/* language tag */
text.lang_key = params[3]; /* translated keyword */
set_text(png_ptr, info_ptr, &text, params[1]);
}
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;
}
int
main(int argc, char **argv)
{
FILE *fp = stdout;
int color_type = 8; /* invalid */
int bit_depth = 32; /* invalid */
png_fixed_point gamma = 0; /* not set */
chunk_insert *head_insert = NULL;
chunk_insert **insert_ptr = &head_insert;
while (--argc > 0)
{
const char *arg = *++argv;
if (strcmp(arg, "--sRGB") == 0)
gamma = PNG_DEFAULT_sRGB;
else if (strcmp(arg, "--linear") == 0)
gamma = PNG_FP_1;
else if (strcmp(arg, "--1.8") == 0)
gamma = PNG_GAMMA_MAC_18;
else 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;
}
}
else if (arg[0] == '-')
{
fprintf(stderr, "makepng: %s: invalid option\n", arg);
exit(1);
}
else if (strcmp(arg, "palette") == 0)
color_type = PNG_COLOR_TYPE_PALETTE;
else if (strncmp(arg, "gray", 4) == 0)
{
color_type = PNG_COLOR_TYPE_GRAY;
if (strcmp(arg+4, "a") == 0 ||
strcmp(arg+4, "alpha") == 0 ||
strcmp(arg+4, "-alpha") == 0)
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
}
else if (strncmp(arg, "rgb", 3) == 0)
{
color_type = PNG_COLOR_TYPE_RGB;
if (strcmp(arg+3, "a") == 0 ||
strcmp(arg+3, "alpha") == 0 ||
strcmp(arg+3, "-alpha") == 0)
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
}
else if (color_type == 8)
{
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);
}
}
else if (bit_depth == 32)
{
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);
}
}
else 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);
}
}
else
{
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-type bit-depth [file-name]\n"
" Make a test PNG file, by default writes to stdout.\n");
exit(1);
}
return write_png(fp, color_type, bit_depth, gamma, head_insert);
}