Transpile libimagequant

codecs/imagequant/imagequant.c

@@ -0,0 +1,67 @@
+#include "emscripten.h"
+#include <stdlib.h>
+#include <inttypes.h>
+
+#include "libimagequant.h"
+
+EMSCRIPTEN_KEEPALIVE
+int version() {
+  return (((LIQ_VERSION/10000) % 100) << 16) |
+         (((LIQ_VERSION/100  ) % 100) << 8) |
+         (((LIQ_VERSION/1    ) % 100) << 0);
+}
+
+EMSCRIPTEN_KEEPALIVE
+uint8_t* create_buffer(int width, int height) {
+  return malloc(width * height * 4 * sizeof(uint8_t));
+}
+
+EMSCRIPTEN_KEEPALIVE
+void destroy_buffer(uint8_t* p) {
+  free(p);
+}
+
+liq_attr *attr;
+liq_image *image;
+liq_result *res;
+int result[2];
+EMSCRIPTEN_KEEPALIVE
+void quantize(uint8_t* image_buffer, int image_width, int image_height, int num_colors, float dithering) {
+  int size = image_width * image_height;
+  attr = liq_attr_create();
+  image = liq_image_create_rgba(attr, image_buffer, image_width, image_height, 0);
+  liq_set_max_colors(attr, 16);
+  liq_image_quantize(image, attr, &res);
+  liq_set_dithering_level(res, dithering);
+  uint8_t* image8bit = (uint8_t*) malloc(size);
+  result[0] = (int) malloc(size * 4);
+  liq_write_remapped_image(res, image, image8bit, size);
+  const liq_palette *pal = liq_get_palette(res);
+  // Turn palletted image back into an RGBA image
+  for(int i = 0; i < size; i++) {
+    ((uint8_t*)result[0])[i * 4 + 0] = pal->entries[image8bit[i]].r;
+    ((uint8_t*)result[0])[i * 4 + 1] = pal->entries[image8bit[i]].g;
+    ((uint8_t*)result[0])[i * 4 + 2] = pal->entries[image8bit[i]].b;
+    ((uint8_t*)result[0])[i * 4 + 3] = pal->entries[image8bit[i]].a;
+  }
+  free(image8bit);
+  liq_result_destroy(res);
+  liq_image_destroy(image);
+  liq_attr_destroy(attr);
+}
+
+EMSCRIPTEN_KEEPALIVE
+void free_result() {
+  free(result[0]);
+}
+
+EMSCRIPTEN_KEEPALIVE
+int get_result_pointer() {
+  return result[0];
+}
+
+EMSCRIPTEN_KEEPALIVE
+int get_result_palette_pointer() {
+  return result[1];
+}
+