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// Copyright 2010 Google Inc.
//
// 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_DECODE_YUV_H_
#define WEBP_DECODE_YUV_H_
#include "webp/decode_vp8.h"
#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];
inline static 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];
}
inline static void VP8YuvToRgba(int y, int u, int v, uint8_t* const rgba) {
VP8YuvToRgb(y, u, v, rgba);
rgba[3] = 0xff;
}
inline static 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];
}
inline static void VP8YuvToBgra(int y, int u, int v, uint8_t* const bgra) {
VP8YuvToBgr(y, u, v, bgra);
bgra[3] = 0xff;
}
// Must be called before everything, to initialize the tables.
void VP8YUVInit();
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif
#endif // WEBP_DECODE_YUV_H_
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