quirc/tests/dbgutil.c
Dmitrij D. Czarkoff 8decf20d4f Strip alpha channel from PNG images with tRNS chunk
When PNG transformations are set up, tRNS chunk is converted to alpha channel
early in the process.  Later the decision whether to strip alpha channel or not
is made upon checking (color_type & PNG_COLOR_MASK_ALPHA).  Thus alpha channel
created by tRNS chunk conversion does not get stripped.
2016-08-15 15:39:18 +02:00

295 lines
7.2 KiB
C

/* quirc -- QR-code recognition library
* Copyright (C) 2010-2012 Daniel Beer <dlbeer@gmail.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <jpeglib.h>
#include <png.h>
#include <quirc.h>
#include "dbgutil.h"
void dump_data(const struct quirc_data *data)
{
static const char *data_type_str[] = {
[QUIRC_DATA_TYPE_NUMERIC] = "NUMERIC",
[QUIRC_DATA_TYPE_ALPHA] = "ALPHANUMERIC",
[QUIRC_DATA_TYPE_BYTE] = "BINARY",
[QUIRC_DATA_TYPE_KANJI] = "KANJI",
};
printf(" Version: %d\n", data->version);
printf(" ECC level: %c\n", "MLHQ"[data->ecc_level]);
printf(" Mask: %d\n", data->mask);
printf(" Data type: %d (%s)\n",
data->data_type, data_type_str[data->data_type]);
printf(" Length: %d\n", data->payload_len);
printf(" Payload: %s\n", data->payload);
}
void dump_cells(const struct quirc_code *code)
{
int u, v;
printf(" %d cells, corners:", code->size);
for (u = 0; u < 4; u++)
printf(" (%d,%d)", code->corners[u].x,
code->corners[u].y);
printf("\n");
for (v = 0; v < code->size; v++) {
printf(" ");
for (u = 0; u < code->size; u++) {
int p = v * code->size + u;
if (code->cell_bitmap[p >> 3] & (1 << (p & 7)))
printf("[]");
else
printf(" ");
}
printf("\n");
}
}
struct my_jpeg_error {
struct jpeg_error_mgr base;
jmp_buf env;
};
static void my_output_message(struct jpeg_common_struct *com)
{
struct my_jpeg_error *err = (struct my_jpeg_error *)com->err;
char buf[JMSG_LENGTH_MAX];
err->base.format_message(com, buf);
fprintf(stderr, "JPEG error: %s", buf);
}
static void my_error_exit(struct jpeg_common_struct *com)
{
struct my_jpeg_error *err = (struct my_jpeg_error *)com->err;
my_output_message(com);
longjmp(err->env, 0);
}
static struct jpeg_error_mgr *my_error_mgr(struct my_jpeg_error *err)
{
jpeg_std_error(&err->base);
err->base.error_exit = my_error_exit;
err->base.output_message = my_output_message;
return &err->base;
}
int load_jpeg(struct quirc *q, const char *filename)
{
FILE *infile = fopen(filename, "rb");
struct jpeg_decompress_struct dinfo;
struct my_jpeg_error err;
uint8_t *image;
int y;
if (!infile) {
perror("can't open input file");
return -1;
}
memset(&dinfo, 0, sizeof(dinfo));
dinfo.err = my_error_mgr(&err);
if (setjmp(err.env))
goto fail;
jpeg_create_decompress(&dinfo);
jpeg_stdio_src(&dinfo, infile);
jpeg_read_header(&dinfo, TRUE);
dinfo.output_components = 1;
dinfo.out_color_space = JCS_GRAYSCALE;
jpeg_start_decompress(&dinfo);
if (dinfo.output_components != 1) {
fprintf(stderr, "Unexpected number of output components: %d",
dinfo.output_components);
goto fail;
}
if (quirc_resize(q, dinfo.output_width, dinfo.output_height) < 0)
goto fail;
image = quirc_begin(q, NULL, NULL);
for (y = 0; y < dinfo.output_height; y++) {
JSAMPROW row_pointer = image + y * dinfo.output_width;
jpeg_read_scanlines(&dinfo, &row_pointer, 1);
}
fclose(infile);
jpeg_finish_decompress(&dinfo);
jpeg_destroy_decompress(&dinfo);
return 0;
fail:
fclose(infile);
jpeg_destroy_decompress(&dinfo);
return -1;
}
/* hacked from https://dev.w3.org/Amaya/libpng/example.c
*
* Check if a file is a PNG image using png_sig_cmp(). Returns 1 if the given
* file is a PNG and 0 otherwise.
*/
#define PNG_BYTES_TO_CHECK 4
int check_if_png(const char *filename)
{
int ret = 0;
FILE *infile = NULL;
unsigned char buf[PNG_BYTES_TO_CHECK];
/* Open the prospective PNG file. */
if ((infile = fopen(filename, "rb")) == NULL)
goto out;
/* Read in some of the signature bytes */
if (fread(buf, 1, PNG_BYTES_TO_CHECK, infile) != PNG_BYTES_TO_CHECK)
goto out;
/*
* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
* png_sig_cmp() returns zero if the image is a PNG and nonzero if it
* isn't a PNG.
*/
if (png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK) == 0)
ret = 1;
/* FALLTHROUGH */
out:
if (infile)
fclose(infile);
return (ret);
}
int load_png(struct quirc *q, const char *filename)
{
int width, height, rowbytes, interlace_type, number_passes = 1;
png_uint_32 trns;
png_byte color_type, bit_depth;
png_structp png_ptr = NULL;
png_infop info_ptr = NULL;
FILE *infile = NULL;
uint8_t *image;
int ret = -1;
int pass;
if ((infile = fopen(filename, "rb")) == NULL)
goto out;
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr)
goto out;
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr)
goto out;
if (setjmp(png_jmpbuf(png_ptr)))
goto out;
png_init_io(png_ptr, infile);
png_read_info(png_ptr, info_ptr);
color_type = png_get_color_type(png_ptr, info_ptr);
bit_depth = png_get_bit_depth(png_ptr, info_ptr);
interlace_type = png_get_interlace_type(png_ptr, info_ptr);
// Read any color_type into 8bit depth, Grayscale format.
// See http://www.libpng.org/pub/png/libpng-manual.txt
// PNG_COLOR_TYPE_GRAY_ALPHA is always 8 or 16bit depth.
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(png_ptr);
if ((trns = png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
png_set_tRNS_to_alpha(png_ptr);
if (bit_depth == 16)
png_set_scale_16(png_ptr);
if ((trns) || color_type & PNG_COLOR_MASK_ALPHA)
png_set_strip_alpha(png_ptr);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
if (color_type == PNG_COLOR_TYPE_PALETTE ||
color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
png_set_rgb_to_gray_fixed(png_ptr, 1, -1, -1);
}
if (interlace_type != PNG_INTERLACE_NONE)
number_passes = png_set_interlace_handling(png_ptr);
png_read_update_info(png_ptr, info_ptr);
width = png_get_image_width(png_ptr, info_ptr);
height = png_get_image_height(png_ptr, info_ptr);
rowbytes = png_get_rowbytes(png_ptr, info_ptr);
if (rowbytes != width) {
fprintf(stderr,
"load_png: expected rowbytes to be %u but got %u\n",
width, rowbytes);
goto out;
}
if (quirc_resize(q, width, height) < 0)
goto out;
image = quirc_begin(q, NULL, NULL);
for (pass = 0; pass < number_passes; pass++) {
int y;
for (y = 0; y < height; y++) {
png_bytep row_pointer = image + y * width;
png_read_rows(png_ptr, &row_pointer, NULL, 1);
}
}
png_read_end(png_ptr, info_ptr);
ret = 0;
/* FALLTHROUGH */
out:
/* cleanup */
if (png_ptr) {
if (info_ptr)
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
else
png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
}
if (infile)
fclose(infile);
return (ret);
}