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add WebPDispatchAlphaToGreen() to dsp

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SSE2 version is 2.1x faster

This is used to transfer the alpha plane to green channel before lossless compression.

Change-Id: I01d9df0051c183b1ff5d6eb69961d4f43e33141a
This commit is contained in:
Pascal Massimino
2014-10-06 23:15:44 +02:00
parent 1bd4c2ad23
commit 2d9b0a4472
4 changed files with 51 additions and 13 deletions
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15
src/dsp/alpha_processing.c
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@@ -303,6 +303,19 @@ static int DispatchAlpha(const uint8_t* alpha, int alpha_stride,
return (alpha_mask != 0xff);
}
static void DispatchAlphaToGreen(const uint8_t* alpha, int alpha_stride,
int width, int height,
uint32_t* dst, int dst_stride) {
int i, j;
for (j = 0; j < height; ++j) {
for (i = 0; i < width; ++i) {
dst[i] = alpha[i] << 8; // leave A/R/B channels zero'd.
}
alpha += alpha_stride;
dst += dst_stride;
}
}
static int ExtractAlpha(const uint8_t* argb, int argb_stride,
int width, int height,
uint8_t* alpha, int alpha_stride) {
@@ -324,6 +337,7 @@ static int ExtractAlpha(const uint8_t* argb, int argb_stride,
void (*WebPApplyAlphaMultiply)(uint8_t*, int, int, int, int);
void (*WebPApplyAlphaMultiply4444)(uint8_t*, int, int, int);
int (*WebPDispatchAlpha)(const uint8_t*, int, int, int, uint8_t*, int);
void (*WebPDispatchAlphaToGreen)(const uint8_t*, int, int, int, uint32_t*, int);
int (*WebPExtractAlpha)(const uint8_t*, int, int, int, uint8_t*, int);
//------------------------------------------------------------------------------
@@ -339,6 +353,7 @@ void WebPInitAlphaProcessing(void) {
WebPApplyAlphaMultiply = ApplyAlphaMultiply;
WebPApplyAlphaMultiply4444 = ApplyAlphaMultiply_16b;
WebPDispatchAlpha = DispatchAlpha;
WebPDispatchAlphaToGreen = DispatchAlphaToGreen;
WebPExtractAlpha = ExtractAlpha;
// If defined, use CPUInfo() to overwrite some pointers with faster versions.