1 files changed, 101 insertions, 0 deletions
diff --git a/src/image.c b/src/image.c
new file mode 100644
index 0000000..dd52b95
--- /dev/null
+++ b/src/image.c
@@ -0,0 +1,101 @@
+#include "image.h"
+#include "common.h"
+
+unsigned decode32(uint32_t** out, unsigned* w, unsigned* h,
+                  unsigned char* in, size_t insize)
+{
+#if defined(USE_LIBPNG)
+    unsigned retval = 1;
+
+    FILE* fp = fmemopen(in, insize, "rb");;
+    png_bytep* row_pointers = NULL;
+
+    if (insize < 8 || png_sig_cmp(in, 0, 8))  abort();
+
+    png_structp png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    png_infop info = png_create_info_struct(png);
+
+    if(setjmp(png_jmpbuf(png))) goto cleanup;
+
+    png_init_io(png, fp);
+    png_read_info(png, info);
+
+    if(png_get_bit_depth(png, info) == 16) png_set_strip_16(png);
+
+    *w = png_get_image_width(png, info);
+    *h = png_get_image_height(png, info);
+
+    png_byte color_type = png_get_color_type(png, info);
+
+    if(color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_palette_to_rgb(png);
+ 
+    if(png_get_valid(png, info, PNG_INFO_tRNS))
+        png_set_tRNS_to_alpha(png);
+
+    row_pointers = local_malloc(sizeof(png_bytep) * *h);
+    *out = local_malloc(sizeof(**out) * (*w * *h));
+    for(int y = 0; y < *h; y++)
+    {
+        row_pointers[y] = (png_byte*)(*out+((*w)*y));
+    }
+
+    png_read_image(png, row_pointers);
+
+    retval = 0;
+
+    cleanup:
+    png_destroy_read_struct(&png, &info, NULL);
+
+    if (fp) fclose(fp);
+    if (row_pointers) free(row_pointers);
+
+    return retval;
+#elif defined(USE_LODEPNG)
+    return lodepng_decode32((unsigned char**)out, w, h, in, insize);
+#else
+    #error "No decode implementation"
+#endif
+}
+
+unsigned encode32_file(const char* filename, const uint32_t* image, unsigned w, unsigned h)
+{
+#if defined(USE_LIBPNG)
+    /* create file */
+    FILE *fp = fopen(filename, "wb");
+    png_bytep* row_pointers = NULL;
+
+    /* initialize stuff */
+    png_structp png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    png_infop info_ptr = png_create_info_struct(png);
+    if(setjmp(png_jmpbuf(png))) goto cleanup;
+
+    png_init_io(png, fp);
+
+
+    png_set_IHDR(png, info_ptr, w, h,
+                 8, PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
+                 PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    png_write_info(png, info_ptr);
+
+    row_pointers = local_malloc(sizeof(png_bytep) * h);
+    for(int y = 0; y < h; y++)
+    {
+        row_pointers[y] = (png_byte*)(image+(w*y));
+    }
+
+    png_write_image(png, row_pointers);
+
+    png_write_end(png, NULL);
+
+    cleanup:
+
+    free(row_pointers);
+    fclose(fp);
+#elif defined(USE_LODEPNG)
+    return lodepng_encode32_file(filename, image, w, h);
+#else
+    #error "No encode implementation"
+#endif
+}
+\ No newline at end of file