#endif
}
+static int ExtractAlpha(const uint8_t* argb, int argb_stride,
+ int width, int height,
+ uint8_t* alpha, int alpha_stride) {
+ uint8_t alpha_mask = 0xff;
+ int i, j;
+
+ for (j = 0; j < height; ++j) {
+ for (i = 0; i < width; ++i) {
+ const uint8_t alpha_value = argb[4 * i];
+ alpha[i] = alpha_value;
+ alpha_mask &= alpha_value;
+ }
+ argb += argb_stride;
+ alpha += alpha_stride;
+ }
+ return (alpha_mask == 0xff);
+}
+
void (*WebPApplyAlphaMultiply)(uint8_t*, int, int, int, int);
void (*WebPApplyAlphaMultiply4444)(uint8_t*, int, int, int);
+int (*WebPExtractAlpha)(const uint8_t*, int, int, int, uint8_t*, int);
//------------------------------------------------------------------------------
// Init function
+extern void WebPInitAlphaProcessingSSE2(void);
+
void WebPInitAlphaProcessing(void) {
WebPMultARGBRow = MultARGBRow;
WebPMultRow = MultRow;
WebPApplyAlphaMultiply = ApplyAlphaMultiply;
WebPApplyAlphaMultiply4444 = ApplyAlphaMultiply_16b;
+ WebPExtractAlpha = ExtractAlpha;
+
+ // If defined, use CPUInfo() to overwrite some pointers with faster versions.
+ if (VP8GetCPUInfo != NULL) {
+#if defined(WEBP_USE_SSE2)
+ if (VP8GetCPUInfo(kSSE2)) {
+ WebPInitAlphaProcessingSSE2();
+ }
+#endif
+ }
}