ref: f9f3bb77618267d94cc2e5102c35e9d036cfcde0
dir: /src/gfx/makepng.c/
/*
* This file is part of RGBDS.
*
* Copyright (c) 2013-2018, stag019 and RGBDS contributors.
*
* SPDX-License-Identifier: MIT
*/
#include <stdlib.h>
#include <string.h>
#include "gfx/main.h"
void input_png_file(const struct Options opts, struct PNGImage *img)
{
FILE *f;
int i, y, num_trans;
bool has_palette = false;
png_byte *trans_alpha;
png_color_16 *trans_values;
bool *full_alpha;
png_color *palette;
f = fopen(opts.infile, "rb");
if (!f)
err(1, "Opening input png file '%s' failed", opts.infile);
img->png = png_create_read_struct(PNG_LIBPNG_VER_STRING,
NULL, NULL, NULL);
if (!img->png)
errx(1, "Creating png structure failed");
img->info = png_create_info_struct(img->png);
if (!img->info)
errx(1, "Creating png info structure failed");
/* TODO: Better error handling here? */
if (setjmp(png_jmpbuf(img->png)))
exit(1);
png_init_io(img->png, f);
png_read_info(img->png, img->info);
img->width = png_get_image_width(img->png, img->info);
img->height = png_get_image_height(img->png, img->info);
img->depth = png_get_bit_depth(img->png, img->info);
img->type = png_get_color_type(img->png, img->info);
if (img->type & PNG_COLOR_MASK_ALPHA)
png_set_strip_alpha(img->png);
if (img->depth != depth) {
if (opts.verbose) {
warnx("Image bit depth is not %i (is %i).", depth,
img->depth);
}
}
if (img->type == PNG_COLOR_TYPE_GRAY) {
if (img->depth < 8)
png_set_expand_gray_1_2_4_to_8(img->png);
png_set_gray_to_rgb(img->png);
} else {
if (img->depth < 8)
png_set_expand_gray_1_2_4_to_8(img->png);
has_palette = png_get_PLTE(img->png, img->info, &palette,
&colors);
}
if (png_get_tRNS(img->png, img->info, &trans_alpha, &num_trans,
&trans_values)) {
if (img->type == PNG_COLOR_TYPE_PALETTE) {
full_alpha = malloc(sizeof(bool) * num_trans);
for (i = 0; i < num_trans; i++) {
if (trans_alpha[i] > 0)
full_alpha[i] = false;
else
full_alpha[i] = true;
}
for (i = 0; i < num_trans; i++) {
if (full_alpha[i]) {
palette[i].red = 0xFF;
palette[i].green = 0x00;
palette[i].blue = 0xFF;
/*
* Set to the lightest color in the
* palette.
*/
}
}
free(full_alpha);
} else {
/* Set to the lightest color in the image. */
}
png_free_data(img->png, img->info, PNG_FREE_TRNS, -1);
}
if (has_palette) {
/* Make sure palette only has the amount of colors you want. */
} else {
/*
* Eventually when this copies colors from the image itself,
* make sure order is lightest to darkest.
*/
palette = malloc(sizeof(png_color) * colors);
if (strcmp(opts.infile, "rgb.png") == 0) {
palette[0].red = 0xFF;
palette[0].green = 0xEF;
palette[0].blue = 0xFF;
palette[1].red = 0xF7;
palette[1].green = 0xF7;
palette[1].blue = 0x8C;
palette[2].red = 0x94;
palette[2].green = 0x94;
palette[2].blue = 0xC6;
palette[3].red = 0x39;
palette[3].green = 0x39;
palette[3].blue = 0x84;
} else {
palette[0].red = 0xFF;
palette[0].green = 0xFF;
palette[0].blue = 0xFF;
palette[1].red = 0xA9;
palette[1].green = 0xA9;
palette[1].blue = 0xA9;
palette[2].red = 0x55;
palette[2].green = 0x55;
palette[2].blue = 0x55;
palette[3].red = 0x00;
palette[3].green = 0x00;
palette[3].blue = 0x00;
}
}
/*
* Also unfortunately, this sets it at 8 bit, and I can't find any
* option to reduce to 2 or 1 bit.
*/
#if PNG_LIBPNG_VER < 10402
png_set_dither(img->png, palette, colors, colors, NULL, 1);
#else
png_set_quantize(img->png, palette, colors, colors, NULL, 1);
#endif
if (!has_palette) {
png_set_PLTE(img->png, img->info, palette, colors);
free(palette);
}
/*
* If other useless chunks exist (sRGB, bKGD, pHYs, gAMA, cHRM, iCCP,
* etc.) offer to remove?
*/
png_read_update_info(img->png, img->info);
img->data = malloc(sizeof(png_byte *) * img->height);
for (y = 0; y < img->height; y++)
img->data[y] = malloc(png_get_rowbytes(img->png, img->info));
png_read_image(img->png, img->data);
png_read_end(img->png, img->info);
fclose(f);
}
void get_text(struct PNGImage *png)
{
png_text *text;
int i, numtxts, numremoved;
png_get_text(png->png, png->info, &text, &numtxts);
for (i = 0; i < numtxts; i++) {
if (strcmp(text[i].key, "h") == 0 && !*text[i].text) {
png->horizontal = true;
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
} else if (strcmp(text[i].key, "x") == 0) {
png->trim = strtoul(text[i].text, NULL, 0);
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
} else if (strcmp(text[i].key, "t") == 0) {
png->mapfile = text[i].text;
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
} else if (strcmp(text[i].key, "T") == 0 && !*text[i].text) {
png->mapout = true;
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
} else if (strcmp(text[i].key, "p") == 0) {
png->palfile = text[i].text;
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
} else if (strcmp(text[i].key, "P") == 0 && !*text[i].text) {
png->palout = true;
png_free_data(png->png, png->info, PNG_FREE_TEXT, i);
}
}
/*
* TODO: Remove this and simply change the warning function not to warn
* instead.
*/
for (i = 0, numremoved = 0; i < numtxts; i++) {
if (text[i].key == NULL)
numremoved++;
text[i].key = text[i + numremoved].key;
text[i].text = text[i + numremoved].text;
text[i].compression = text[i + numremoved].compression;
}
png_set_text(png->png, png->info, text, numtxts - numremoved);
}
void set_text(const struct PNGImage *png)
{
png_text *text;
char buffer[3];
text = malloc(sizeof(png_text));
if (png->horizontal) {
text[0].key = "h";
text[0].text = "";
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
if (png->trim) {
text[0].key = "x";
snprintf(buffer, 3, "%d", png->trim);
text[0].text = buffer;
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
if (*png->mapfile) {
text[0].key = "t";
text[0].text = "";
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
if (png->mapout) {
text[0].key = "T";
text[0].text = "";
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
if (*png->palfile) {
text[0].key = "p";
text[0].text = "";
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
if (png->palout) {
text[0].key = "P";
text[0].text = "";
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
png_set_text(png->png, png->info, text, 1);
}
free(text);
}
void output_png_file(const struct Options opts, const struct PNGImage *png)
{
FILE *f;
char *outfile;
png_struct *img;
/*
* TODO: Variable outfile is for debugging purposes. Eventually,
* opts.infile will be used directly.
*/
if (opts.debug) {
outfile = malloc(strlen(opts.infile) + 5);
strcpy(outfile, opts.infile);
strcat(outfile, ".out");
} else {
outfile = opts.infile;
}
f = fopen(outfile, "wb");
if (!f)
err(1, "Opening output png file '%s' failed", outfile);
img = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!img)
errx(1, "Creating png structure failed");
/* TODO: Better error handling here? */
if (setjmp(png_jmpbuf(img)))
exit(1);
png_init_io(img, f);
png_write_info(img, png->info);
png_write_image(img, png->data);
png_write_end(img, NULL);
fclose(f);
if (opts.debug)
free(outfile);
}
void free_png_data(const struct PNGImage *png)
{
int y;
for (y = 0; y < png->height; y++)
free(png->data[y]);
free(png->data);
}