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Diffstat (limited to 'drivers/webpold/dsp/yuv.h')
-rw-r--r-- | drivers/webpold/dsp/yuv.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/webpold/dsp/yuv.h b/drivers/webpold/dsp/yuv.h new file mode 100644 index 0000000000..a569109c54 --- /dev/null +++ b/drivers/webpold/dsp/yuv.h @@ -0,0 +1,128 @@ +// Copyright 2010 Google Inc. All Rights Reserved. +// +// This code is licensed under the same terms as WebM: +// Software License Agreement: http://www.webmproject.org/license/software/ +// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ +// ----------------------------------------------------------------------------- +// +// inline YUV<->RGB conversion function +// +// Author: Skal (pascal.massimino@gmail.com) + +#ifndef WEBP_DSP_YUV_H_ +#define WEBP_DSP_YUV_H_ + +#include "../dec/decode_vp8.h" + +//------------------------------------------------------------------------------ +// YUV -> RGB conversion + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +enum { YUV_FIX = 16, // fixed-point precision + YUV_RANGE_MIN = -227, // min value of r/g/b output + YUV_RANGE_MAX = 256 + 226 // max value of r/g/b output +}; +extern int16_t VP8kVToR[256], VP8kUToB[256]; +extern int32_t VP8kVToG[256], VP8kUToG[256]; +extern uint8_t VP8kClip[YUV_RANGE_MAX - YUV_RANGE_MIN]; +extern uint8_t VP8kClip4Bits[YUV_RANGE_MAX - YUV_RANGE_MIN]; + +static WEBP_INLINE void VP8YuvToRgb(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const rgb) { + 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]; + rgb[1] = VP8kClip[y + g_off - YUV_RANGE_MIN]; + rgb[2] = VP8kClip[y + b_off - YUV_RANGE_MIN]; +} + +static WEBP_INLINE void VP8YuvToRgb565(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const rgb) { + 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)); +} + +static WEBP_INLINE void VP8YuvToArgb(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const argb) { + argb[0] = 0xff; + VP8YuvToRgb(y, u, v, argb + 1); +} + +static WEBP_INLINE void VP8YuvToRgba4444(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const argb) { + 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); +} + +static WEBP_INLINE void VP8YuvToBgr(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const bgr) { + const int r_off = VP8kVToR[v]; + const int g_off = (VP8kVToG[v] + VP8kUToG[u]) >> YUV_FIX; + const int b_off = VP8kUToB[u]; + bgr[0] = VP8kClip[y + b_off - YUV_RANGE_MIN]; + bgr[1] = VP8kClip[y + g_off - YUV_RANGE_MIN]; + bgr[2] = VP8kClip[y + r_off - YUV_RANGE_MIN]; +} + +static WEBP_INLINE void VP8YuvToBgra(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const bgra) { + VP8YuvToBgr(y, u, v, bgra); + bgra[3] = 0xff; +} + +static WEBP_INLINE void VP8YuvToRgba(uint8_t y, uint8_t u, uint8_t v, + uint8_t* const rgba) { + VP8YuvToRgb(y, u, v, rgba); + rgba[3] = 0xff; +} + +// Must be called before everything, to initialize the tables. +void VP8YUVInit(void); + +//------------------------------------------------------------------------------ +// RGB -> YUV conversion +// The exact naming is Y'CbCr, following the ITU-R BT.601 standard. +// More information at: http://en.wikipedia.org/wiki/YCbCr +// Y = 0.2569 * R + 0.5044 * G + 0.0979 * B + 16 +// U = -0.1483 * R - 0.2911 * G + 0.4394 * B + 128 +// V = 0.4394 * R - 0.3679 * G - 0.0715 * B + 128 +// We use 16bit fixed point operations. + +static WEBP_INLINE int VP8ClipUV(int v) { + v = (v + (257 << (YUV_FIX + 2 - 1))) >> (YUV_FIX + 2); + return ((v & ~0xff) == 0) ? v : (v < 0) ? 0 : 255; +} + +static WEBP_INLINE int VP8RGBToY(int r, int g, int b) { + const int kRound = (1 << (YUV_FIX - 1)) + (16 << YUV_FIX); + const int luma = 16839 * r + 33059 * g + 6420 * b; + return (luma + kRound) >> YUV_FIX; // no need to clip +} + +static WEBP_INLINE int VP8RGBToU(int r, int g, int b) { + return VP8ClipUV(-9719 * r - 19081 * g + 28800 * b); +} + +static WEBP_INLINE int VP8RGBToV(int r, int g, int b) { + return VP8ClipUV(+28800 * r - 24116 * g - 4684 * b); +} + +#if defined(__cplusplus) || defined(c_plusplus) +} // extern "C" +#endif + +#endif /* WEBP_DSP_YUV_H_ */ |