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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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16
src/enc/alpha.c
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@ -61,18 +61,8 @@ static int EncodeLossless(const uint8_t* const data, int width, int height,
if (!WebPPictureAlloc(&picture)) return 0;
// Transfer the alpha values to the green channel.
{
int i, j;
uint32_t* dst = picture.argb;
const uint8_t* src = data;
for (j = 0; j < picture.height; ++j) {
for (i = 0; i < picture.width; ++i) {
dst[i] = src[i] << 8; // we leave A/R/B channels zero'd.
}
src += width;
dst += picture.argb_stride;
}
}
WebPDispatchAlphaToGreen(data, width, picture.width, picture.height,
picture.argb, picture.argb_stride);
WebPConfigInit(&config);
config.lossless = 1;
@ -376,6 +366,7 @@ static int CompressAlphaJob(VP8Encoder* const enc, void* dummy) {
}
void VP8EncInitAlpha(VP8Encoder* const enc) {
WebPInitAlphaProcessing();
enc->has_alpha_ = WebPPictureHasTransparency(enc->pic_);
enc->alpha_data_ = NULL;
enc->alpha_data_size_ = 0;
@ -430,4 +421,3 @@ int VP8EncDeleteAlpha(VP8Encoder* const enc) {
enc->has_alpha_ = 0;
return ok;
}