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Provide option to swap bytes for 16 bit colormodes

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Color modes: RGB_565 & RGBA_4444
Change-Id: I571b6832b9848e5c4109272978f68623ca373383
This commit is contained in:
Vikas Arora
2013-01-18 16:23:09 -08:00
parent 1d2702b1da
commit 94a48b4bc3
6 changed files with 64 additions and 14 deletions
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29
src/dsp/yuv.h
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@ -62,10 +62,17 @@ static WEBP_INLINE void VP8YuvToRgb565(uint8_t y, uint8_t u, uint8_t v,
const int r_off = VP8kVToR[v];
const int g_off = (VP8kVToG[v] + VP8kUToG[u]) >> YUV_FIX;
const int b_off = VP8kUToB[u];
rgb[0] = ((VP8kClip[y + r_off - YUV_RANGE_MIN] & 0xf8) |
(VP8kClip[y + g_off - YUV_RANGE_MIN] >> 5));
rgb[1] = (((VP8kClip[y + g_off - YUV_RANGE_MIN] << 3) & 0xe0) |
(VP8kClip[y + b_off - YUV_RANGE_MIN] >> 3));
const uint8_t rg = ((VP8kClip[y + r_off - YUV_RANGE_MIN] & 0xf8) |
(VP8kClip[y + g_off - YUV_RANGE_MIN] >> 5));
const uint8_t gb = (((VP8kClip[y + g_off - YUV_RANGE_MIN] << 3) & 0xe0) |
(VP8kClip[y + b_off - YUV_RANGE_MIN] >> 3));
#ifdef WEBP_SWAP_16BIT_CSP
rgb[0] = gb;
rgb[1] = rg;
#else
rgb[0] = rg;
rgb[1] = gb;
#endif
}
static WEBP_INLINE void VP8YuvToArgb(uint8_t y, uint8_t u, uint8_t v,
@ -79,10 +86,16 @@ static WEBP_INLINE void VP8YuvToRgba4444(uint8_t y, uint8_t u, uint8_t v,
const int r_off = VP8kVToR[v];
const int g_off = (VP8kVToG[v] + VP8kUToG[u]) >> YUV_FIX;
const int b_off = VP8kUToB[u];
// Don't update alpha (last 4 bits of argb[1])
argb[0] = ((VP8kClip4Bits[y + r_off - YUV_RANGE_MIN] << 4) |
VP8kClip4Bits[y + g_off - YUV_RANGE_MIN]);
argb[1] = 0x0f | (VP8kClip4Bits[y + b_off - YUV_RANGE_MIN] << 4);
const uint8_t rg = ((VP8kClip4Bits[y + r_off - YUV_RANGE_MIN] << 4) |
VP8kClip4Bits[y + g_off - YUV_RANGE_MIN]);
const uint8_t ba = (VP8kClip4Bits[y + b_off - YUV_RANGE_MIN] << 4) | 0x0f;
#ifdef WEBP_SWAP_16BIT_CSP
argb[0] = ba;
argb[1] = rg;
#else
argb[0] = rg;
argb[1] = ba;
#endif
}
static WEBP_INLINE void VP8YuvToBgr(uint8_t y, uint8_t u, uint8_t v,