yuv.c revision 8b720228d581a84fd173b6dcb2fa295b59db489a 
1// Copyright 2010 Google Inc. All Rights Reserved.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the COPYING file in the root of the source
5// tree. An additional intellectual property rights grant can be found
6// in the file PATENTS. All contributing project authors may
7// be found in the AUTHORS file in the root of the source tree.
8// -----------------------------------------------------------------------------
9//
10// YUV->RGB conversion function
11//
12// Author: Skal (pascal.massimino@gmail.com)
13
14#include "./yuv.h"
15
16
17#if defined(WEBP_YUV_USE_TABLE)
18
19static int done = 0;
20
21static WEBP_INLINE uint8_t clip(int v, int max_value) {
22  return v < 0 ? 0 : v > max_value ? max_value : v;
23}
24
25int16_t VP8kVToR[256], VP8kUToB[256];
26int32_t VP8kVToG[256], VP8kUToG[256];
27uint8_t VP8kClip[YUV_RANGE_MAX - YUV_RANGE_MIN];
28uint8_t VP8kClip4Bits[YUV_RANGE_MAX - YUV_RANGE_MIN];
29
30void VP8YUVInit(void) {
31  int i;
32  if (done) {
33    return;
34  }
35#ifndef USE_YUVj
36  for (i = 0; i < 256; ++i) {
37    VP8kVToR[i] = (89858 * (i - 128) + YUV_HALF) >> YUV_FIX;
38    VP8kUToG[i] = -22014 * (i - 128) + YUV_HALF;
39    VP8kVToG[i] = -45773 * (i - 128);
40    VP8kUToB[i] = (113618 * (i - 128) + YUV_HALF) >> YUV_FIX;
41  }
42  for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) {
43    const int k = ((i - 16) * 76283 + YUV_HALF) >> YUV_FIX;
44    VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255);
45    VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15);
46  }
47#else
48  for (i = 0; i < 256; ++i) {
49    VP8kVToR[i] = (91881 * (i - 128) + YUV_HALF) >> YUV_FIX;
50    VP8kUToG[i] = -22554 * (i - 128) + YUV_HALF;
51    VP8kVToG[i] = -46802 * (i - 128);
52    VP8kUToB[i] = (116130 * (i - 128) + YUV_HALF) >> YUV_FIX;
53  }
54  for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) {
55    const int k = i;
56    VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255);
57    VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15);
58  }
59#endif
60
61  done = 1;
62}
63
64#else
65
66void VP8YUVInit(void) {}
67
68#endif  // WEBP_YUV_USE_TABLE
69
70//-----------------------------------------------------------------------------
71// SSE2 extras
72
73#if defined(WEBP_USE_SSE2)
74
75#ifdef FANCY_UPSAMPLING
76
77#include <emmintrin.h>
78#include <string.h>   // for memcpy
79
80typedef union {   // handy struct for converting SSE2 registers
81  int32_t i32[4];
82  uint8_t u8[16];
83  __m128i m;
84} VP8kCstSSE2;
85
86static int done_sse2 = 0;
87static VP8kCstSSE2 VP8kUtoRGBA[256], VP8kVtoRGBA[256], VP8kYtoRGBA[256];
88
89void VP8YUVInitSSE2(void) {
90  if (!done_sse2) {
91    int i;
92    for (i = 0; i < 256; ++i) {
93      VP8kYtoRGBA[i].i32[0] =
94        VP8kYtoRGBA[i].i32[1] =
95        VP8kYtoRGBA[i].i32[2] = (i - 16) * kYScale + YUV_HALF2;
96      VP8kYtoRGBA[i].i32[3] = 0xff << YUV_FIX2;
97
98      VP8kUtoRGBA[i].i32[0] = 0;
99      VP8kUtoRGBA[i].i32[1] = -kUToG * (i - 128);
100      VP8kUtoRGBA[i].i32[2] =  kUToB * (i - 128);
101      VP8kUtoRGBA[i].i32[3] = 0;
102
103      VP8kVtoRGBA[i].i32[0] =  kVToR * (i - 128);
104      VP8kVtoRGBA[i].i32[1] = -kVToG * (i - 128);
105      VP8kVtoRGBA[i].i32[2] = 0;
106      VP8kVtoRGBA[i].i32[3] = 0;
107    }
108    done_sse2 = 1;
109  }
110}
111
112static WEBP_INLINE __m128i VP8GetRGBA32b(int y, int u, int v) {
113  const __m128i u_part = _mm_loadu_si128(&VP8kUtoRGBA[u].m);
114  const __m128i v_part = _mm_loadu_si128(&VP8kVtoRGBA[v].m);
115  const __m128i y_part = _mm_loadu_si128(&VP8kYtoRGBA[y].m);
116  const __m128i uv_part = _mm_add_epi32(u_part, v_part);
117  const __m128i rgba1 = _mm_add_epi32(y_part, uv_part);
118  const __m128i rgba2 = _mm_srai_epi32(rgba1, YUV_FIX2);
119  return rgba2;
120}
121
122static WEBP_INLINE void VP8YuvToRgbSSE2(uint8_t y, uint8_t u, uint8_t v,
123                                        uint8_t* const rgb) {
124  const __m128i tmp0 = VP8GetRGBA32b(y, u, v);
125  const __m128i tmp1 = _mm_packs_epi32(tmp0, tmp0);
126  const __m128i tmp2 = _mm_packus_epi16(tmp1, tmp1);
127  // Note: we store 8 bytes at a time, not 3 bytes! -> memory stomp
128  _mm_storel_epi64((__m128i*)rgb, tmp2);
129}
130
131static WEBP_INLINE void VP8YuvToBgrSSE2(uint8_t y, uint8_t u, uint8_t v,
132                                        uint8_t* const bgr) {
133  const __m128i tmp0 = VP8GetRGBA32b(y, u, v);
134  const __m128i tmp1 = _mm_shuffle_epi32(tmp0, _MM_SHUFFLE(3, 0, 1, 2));
135  const __m128i tmp2 = _mm_packs_epi32(tmp1, tmp1);
136  const __m128i tmp3 = _mm_packus_epi16(tmp2, tmp2);
137  // Note: we store 8 bytes at a time, not 3 bytes! -> memory stomp
138  _mm_storel_epi64((__m128i*)bgr, tmp3);
139}
140
141void VP8YuvToRgba32(const uint8_t* y, const uint8_t* u, const uint8_t* v,
142                    uint8_t* dst) {
143  int n;
144  for (n = 0; n < 32; n += 4) {
145    const __m128i tmp0_1 = VP8GetRGBA32b(y[n + 0], u[n + 0], v[n + 0]);
146    const __m128i tmp0_2 = VP8GetRGBA32b(y[n + 1], u[n + 1], v[n + 1]);
147    const __m128i tmp0_3 = VP8GetRGBA32b(y[n + 2], u[n + 2], v[n + 2]);
148    const __m128i tmp0_4 = VP8GetRGBA32b(y[n + 3], u[n + 3], v[n + 3]);
149    const __m128i tmp1_1 = _mm_packs_epi32(tmp0_1, tmp0_2);
150    const __m128i tmp1_2 = _mm_packs_epi32(tmp0_3, tmp0_4);
151    const __m128i tmp2 = _mm_packus_epi16(tmp1_1, tmp1_2);
152    _mm_storeu_si128((__m128i*)dst, tmp2);
153    dst += 4 * 4;
154  }
155}
156
157void VP8YuvToBgra32(const uint8_t* y, const uint8_t* u, const uint8_t* v,
158                    uint8_t* dst) {
159  int n;
160  for (n = 0; n < 32; n += 2) {
161    const __m128i tmp0_1 = VP8GetRGBA32b(y[n + 0], u[n + 0], v[n + 0]);
162    const __m128i tmp0_2 = VP8GetRGBA32b(y[n + 1], u[n + 1], v[n + 1]);
163    const __m128i tmp1_1 = _mm_shuffle_epi32(tmp0_1, _MM_SHUFFLE(3, 0, 1, 2));
164    const __m128i tmp1_2 = _mm_shuffle_epi32(tmp0_2, _MM_SHUFFLE(3, 0, 1, 2));
165    const __m128i tmp2_1 = _mm_packs_epi32(tmp1_1, tmp1_2);
166    const __m128i tmp3 = _mm_packus_epi16(tmp2_1, tmp2_1);
167    _mm_storel_epi64((__m128i*)dst, tmp3);
168    dst += 4 * 2;
169  }
170}
171
172void VP8YuvToRgb32(const uint8_t* y, const uint8_t* u, const uint8_t* v,
173                   uint8_t* dst) {
174  int n;
175  uint8_t tmp0[2 * 3 + 5 + 15];
176  uint8_t* const tmp = (uint8_t*)((uintptr_t)(tmp0 + 15) & ~15);  // align
177  for (n = 0; n < 30; ++n) {   // we directly stomp the *dst memory
178    VP8YuvToRgbSSE2(y[n], u[n], v[n], dst + n * 3);
179  }
180  // Last two pixels are special: we write in a tmp buffer before sending
181  // to dst.
182  VP8YuvToRgbSSE2(y[n + 0], u[n + 0], v[n + 0], tmp + 0);
183  VP8YuvToRgbSSE2(y[n + 1], u[n + 1], v[n + 1], tmp + 3);
184  memcpy(dst + n * 3, tmp, 2 * 3);
185}
186
187void VP8YuvToBgr32(const uint8_t* y, const uint8_t* u, const uint8_t* v,
188                   uint8_t* dst) {
189  int n;
190  uint8_t tmp0[2 * 3 + 5 + 15];
191  uint8_t* const tmp = (uint8_t*)((uintptr_t)(tmp0 + 15) & ~15);  // align
192  for (n = 0; n < 30; ++n) {
193    VP8YuvToBgrSSE2(y[n], u[n], v[n], dst + n * 3);
194  }
195  VP8YuvToBgrSSE2(y[n + 0], u[n + 0], v[n + 0], tmp + 0);
196  VP8YuvToBgrSSE2(y[n + 1], u[n + 1], v[n + 1], tmp + 3);
197  memcpy(dst + n * 3, tmp, 2 * 3);
198}
199
200#else
201
202void VP8YUVInitSSE2(void) {}
203
204#endif  // FANCY_UPSAMPLING
205
206#endif  // WEBP_USE_SSE2
207
208