diff options
Diffstat (limited to 'tools/make_lang_png_transparent.c')
| -rw-r--r-- | tools/make_lang_png_transparent.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/tools/make_lang_png_transparent.c b/tools/make_lang_png_transparent.c new file mode 100644 index 000000000..9a037e864 --- /dev/null +++ b/tools/make_lang_png_transparent.c @@ -0,0 +1,167 @@ +/* + * Guillaume Cottenceau (gc at mandriva.com) + * + * Copyright 2002-2005 Mandriva + * + * This software may be freely redistributed under the terms of the GNU + * public license. + * + */ + +#include <unistd.h> +#include <stdio.h> +#include <string.h> +#include <stdarg.h> + +#define PNG_DEBUG 3 +#include <png.h> + +void abort_(const char * s, ...) +{ + va_list args; + va_start(args, s); + vfprintf(stderr, s, args); + fprintf(stderr, "\n"); + va_end(args); + abort(); +} + +int x, y; + +int width, height; +png_byte color_type; +png_byte bit_depth; + +png_structp png_ptr; +png_infop info_ptr; +int number_of_passes; +png_bytep * row_pointers; + +void read_png_file(char* file_name) +{ + char header[8]; // 8 is the maximum size that can be checked + + /* open file and test for it being a png */ + FILE *fp = fopen(file_name, "rb"); + if (!fp) + abort_("[read_png_file] File %s could not be opened for reading", file_name); + fread(header, 1, 8, fp); + if (png_sig_cmp(header, 0, 8)) + abort_("[read_png_file] File %s is not recognized as a PNG file", file_name); + + + /* initialize stuff */ + png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); + + if (!png_ptr) + abort_("[read_png_file] png_create_read_struct failed"); + + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + abort_("[read_png_file] png_create_info_struct failed"); + + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[read_png_file] Error during init_io"); + + png_init_io(png_ptr, fp); + png_set_sig_bytes(png_ptr, 8); + + png_read_info(png_ptr, info_ptr); + + width = info_ptr->width; + height = info_ptr->height; + color_type = info_ptr->color_type; + bit_depth = info_ptr->bit_depth; + + number_of_passes = png_set_interlace_handling(png_ptr); + png_read_update_info(png_ptr, info_ptr); + + + /* read file */ + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[read_png_file] Error during read_image"); + + row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * height); + for (y=0; y<height; y++) + row_pointers[y] = (png_byte*) malloc(info_ptr->rowbytes); + + png_read_image(png_ptr, row_pointers); +} + + +void write_png_file(char* file_name) +{ + /* create file */ + FILE *fp = fopen(file_name, "wb"); + if (!fp) + abort_("[write_png_file] File %s could not be opened for writing", file_name); + + + /* initialize stuff */ + png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); + + if (!png_ptr) + abort_("[write_png_file] png_create_write_struct failed"); + + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + abort_("[write_png_file] png_create_info_struct failed"); + + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[write_png_file] Error during init_io"); + + png_init_io(png_ptr, fp); + + + /* write header */ + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[write_png_file] Error during writing header"); + + png_set_IHDR(png_ptr, info_ptr, width, height, + bit_depth, color_type, PNG_INTERLACE_NONE, + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); + + png_write_info(png_ptr, info_ptr); + + + /* write bytes */ + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[write_png_file] Error during writing bytes"); + + png_write_image(png_ptr, row_pointers); + + + /* end write */ + if (setjmp(png_jmpbuf(png_ptr))) + abort_("[write_png_file] Error during end of write"); + + png_write_end(png_ptr, NULL); + +} + +void process_file(void) +{ + if (info_ptr->color_type != PNG_COLOR_TYPE_RGBA) + abort_("[process_file] color_type of input file must be PNG_COLOR_TYPE_RGBA (is %d)", info_ptr->color_type); + + for (y=0; y<height; y++) { + png_byte* row = row_pointers[y]; + for (x=0; x<width; x++) { + png_byte* ptr = &(row[x*4]); + ptr[3] = 255-ptr[0]; + ptr[0] = ptr[1] = ptr[2] = 0; + } + } + +} + + +int main(int argc, char **argv) +{ + if (argc != 3) + abort_("Usage: program_name <file_in> <file_out>"); + + read_png_file(argv[1]); + process_file(); + write_png_file(argv[2]); +} |