diff options
Diffstat (limited to 'drivers/webpold/dsp/yuv.c')
-rw-r--r-- | drivers/webpold/dsp/yuv.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/drivers/webpold/dsp/yuv.c b/drivers/webpold/dsp/yuv.c new file mode 100644 index 0000000000..7f05f9a3aa --- /dev/null +++ b/drivers/webpold/dsp/yuv.c @@ -0,0 +1,52 @@ +// 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/ +// ----------------------------------------------------------------------------- +// +// YUV->RGB conversion function +// +// Author: Skal (pascal.massimino@gmail.com) + +#include "./yuv.h" + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +enum { YUV_HALF = 1 << (YUV_FIX - 1) }; + +int16_t VP8kVToR[256], VP8kUToB[256]; +int32_t VP8kVToG[256], VP8kUToG[256]; +uint8_t VP8kClip[YUV_RANGE_MAX - YUV_RANGE_MIN]; +uint8_t VP8kClip4Bits[YUV_RANGE_MAX - YUV_RANGE_MIN]; + +static int done = 0; + +static WEBP_INLINE uint8_t clip(int v, int max_value) { + return v < 0 ? 0 : v > max_value ? max_value : v; +} + +void VP8YUVInit(void) { + int i; + if (done) { + return; + } + for (i = 0; i < 256; ++i) { + VP8kVToR[i] = (89858 * (i - 128) + YUV_HALF) >> YUV_FIX; + VP8kUToG[i] = -22014 * (i - 128) + YUV_HALF; + VP8kVToG[i] = -45773 * (i - 128); + VP8kUToB[i] = (113618 * (i - 128) + YUV_HALF) >> YUV_FIX; + } + for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) { + const int k = ((i - 16) * 76283 + YUV_HALF) >> YUV_FIX; + VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255); + VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15); + } + done = 1; +} + +#if defined(__cplusplus) || defined(c_plusplus) +} // extern "C" +#endif |