// Copyright 2010 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// YUV->RGB conversion functions
//
// Author: Skal (pascal.massimino@gmail.com)
#include "./yuv.h"
#if defined(WEBP_YUV_USE_TABLE)
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;
}
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];
void VP8YUVInit(void) {
int i;
if (done) {
return;
}
#ifndef USE_YUVj
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);
}
#else
for (i = 0; i < 256; ++i) {
VP8kVToR[i] = (91881 * (i - 128) + YUV_HALF) >> YUV_FIX;
VP8kUToG[i] = -22554 * (i - 128) + YUV_HALF;
VP8kVToG[i] = -46802 * (i - 128);
VP8kUToB[i] = (116130 * (i - 128) + YUV_HALF) >> YUV_FIX;
}
for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) {
const int k = i;
VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255);
VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15);
}
#endif
done = 1;
}
#else
void VP8YUVInit(void) {}
#endif // WEBP_YUV_USE_TABLE
//-----------------------------------------------------------------------------
// Plain-C version
#define ROW_FUNC(FUNC_NAME, FUNC, XSTEP) \
static void FUNC_NAME(const uint8_t* y, \
const uint8_t* u, const uint8_t* v, \
uint8_t* dst, int len) { \
const uint8_t* const end = dst + (len & ~1) * XSTEP; \
while (dst != end) { \
FUNC(y[0], u[0], v[0], dst); \
FUNC(y[1], u[0], v[0], dst + XSTEP); \
y += 2; \
++u; \
++v; \
dst += 2 * XSTEP; \
} \
if (len & 1) { \
FUNC(y[0], u[0], v[0], dst); \
} \
} \
// All variants implemented.
ROW_FUNC(YuvToRgbRow, VP8YuvToRgb, 3)
ROW_FUNC(YuvToBgrRow, VP8YuvToBgr, 3)
ROW_FUNC(YuvToRgbaRow, VP8YuvToRgba, 4)
ROW_FUNC(YuvToBgraRow, VP8YuvToBgra, 4)
ROW_FUNC(YuvToArgbRow, VP8YuvToArgb, 4)
ROW_FUNC(YuvToRgba4444Row, VP8YuvToRgba4444, 2)
ROW_FUNC(YuvToRgb565Row, VP8YuvToRgb565, 2)
#undef ROW_FUNC
// Main call for processing a plane with a WebPSamplerRowFunc function:
void WebPSamplerProcessPlane(const uint8_t* y, int y_stride,
const uint8_t* u, const uint8_t* v, int uv_stride,
uint8_t* dst, int dst_stride,
int width, int height, WebPSamplerRowFunc func) {
int j;
for (j = 0; j < height; ++j) {
func(y, u, v, dst, width);
y += y_stride;
if (j & 1) {
u += uv_stride;
v += uv_stride;
}
dst += dst_stride;
}
}
//-----------------------------------------------------------------------------
// Main call
WebPSamplerRowFunc WebPSamplers[MODE_LAST];
extern void WebPInitSamplersSSE2(void);
extern void WebPInitSamplersMIPS32(void);
void WebPInitSamplers(void) {
WebPSamplers[MODE_RGB] = YuvToRgbRow;
WebPSamplers[MODE_RGBA] = YuvToRgbaRow;
WebPSamplers[MODE_BGR] = YuvToBgrRow;
WebPSamplers[MODE_BGRA] = YuvToBgraRow;
WebPSamplers[MODE_ARGB] = YuvToArgbRow;
WebPSamplers[MODE_RGBA_4444] = YuvToRgba4444Row;
WebPSamplers[MODE_RGB_565] = YuvToRgb565Row;
WebPSamplers[MODE_rgbA] = YuvToRgbaRow;
WebPSamplers[MODE_bgrA] = YuvToBgraRow;
WebPSamplers[MODE_Argb] = YuvToArgbRow;
WebPSamplers[MODE_rgbA_4444] = YuvToRgba4444Row;
// If defined, use CPUInfo() to overwrite some pointers with faster versions.
if (VP8GetCPUInfo != NULL) {
#if defined(WEBP_USE_SSE2)
if (VP8GetCPUInfo(kSSE2)) {
WebPInitSamplersSSE2();
}
#endif // WEBP_USE_SSE2
#if defined(WEBP_USE_MIPS32)
if (VP8GetCPUInfo(kMIPS32)) {
WebPInitSamplersMIPS32();
}
#endif // WEBP_USE_MIPS32
}
}
//-----------------------------------------------------------------------------
