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#include <SDL2/SDL.h>
#include <string.h>
#include <jpeglib.h>
#include <setjmp.h>
SDL_Texture* imv_load_jpeg(SDL_Renderer *r, const char* path)
{
FILE *fp = fopen(path, "rb");
if(!fp) {
return NULL;
}
struct jpeg_decompress_struct cinfo;
jpeg_create_decompress(&cinfo);
struct jpeg_error_mgr jerr;
cinfo.err = jpeg_std_error(&jerr);
jpeg_stdio_src(&cinfo, fp);
jpeg_read_header(&cinfo, TRUE);
jpeg_start_decompress(&cinfo);
int row_stride = cinfo.output_width * cinfo.output_components;
JSAMPARRAY buffer = (*cinfo.mem->alloc_sarray)
((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
char* pixels = (char*)malloc(row_stride*cinfo.output_height);
while (cinfo.output_scanline < cinfo.output_height) {
jpeg_read_scanlines(&cinfo, buffer, 1);
void *out_row = pixels + row_stride * (cinfo.output_scanline-1);
memcpy(out_row, buffer[0], row_stride);
}
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
fclose(fp);
SDL_Texture *img = SDL_CreateTexture(r,
SDL_PIXELFORMAT_RGB24, SDL_TEXTUREACCESS_STATIC,
cinfo.output_width, cinfo.output_height);
SDL_Rect area = {0,0,cinfo.output_width,cinfo.output_height};
SDL_UpdateTexture(img, &area, pixels, row_stride);
free(pixels);
return img;
}
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