1// Copyright 2022 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// Sharp RGB to YUV conversion.
11//
12// Author: Skal (pascal.massimino@gmail.com)
13
14#include "sharpyuv/sharpyuv.h"
15
16#include <assert.h>
17#include <limits.h>
18#include <stddef.h>
19#include <stdlib.h>
20#include <string.h>
21
22#include "src/webp/types.h"
23#include "sharpyuv/sharpyuv_cpu.h"
24#include "sharpyuv/sharpyuv_dsp.h"
25#include "sharpyuv/sharpyuv_gamma.h"
26
27//------------------------------------------------------------------------------
28
29int SharpYuvGetVersion(void) {
30 return SHARPYUV_VERSION;
31}
32
33//------------------------------------------------------------------------------
34// Sharp RGB->YUV conversion
35
36static const int kNumIterations = 4;
37
38#define YUV_FIX 16 // fixed-point precision for RGB->YUV
39static const int kYuvHalf = 1 << (YUV_FIX - 1);
40
41// Max bit depth so that intermediate calculations fit in 16 bits.
42static const int kMaxBitDepth = 14;
43
44// Returns the precision shift to use based on the input rgb_bit_depth.
45static int GetPrecisionShift(int rgb_bit_depth) {
46 // Try to add 2 bits of precision if it fits in kMaxBitDepth. Otherwise remove
47 // bits if needed.
48 return ((rgb_bit_depth + 2) <= kMaxBitDepth) ? 2
49 : (kMaxBitDepth - rgb_bit_depth);
50}
51
52typedef int16_t fixed_t; // signed type with extra precision for UV
53typedef uint16_t fixed_y_t; // unsigned type with extra precision for W
54
55//------------------------------------------------------------------------------
56
57static uint8_t clip_8b(fixed_t v) {
58 return (!(v & ~0xff)) ? (uint8_t)v : (v < 0) ? 0u : 255u;
59}
60
61static uint16_t clip(fixed_t v, int max) {
62 return (v < 0) ? 0 : (v > max) ? max : (uint16_t)v;
63}
64
65static fixed_y_t clip_bit_depth(int y, int bit_depth) {
66 const int max = (1 << bit_depth) - 1;
67 return (!(y & ~max)) ? (fixed_y_t)y : (y < 0) ? 0 : max;
68}
69
70//------------------------------------------------------------------------------
71
72static int RGBToGray(int64_t r, int64_t g, int64_t b) {
73 const int64_t luma = 13933 * r + 46871 * g + 4732 * b + kYuvHalf;
74 return (int)(luma >> YUV_FIX);
75}
76
77static uint32_t ScaleDown(uint16_t a, uint16_t b, uint16_t c, uint16_t d,
78 int rgb_bit_depth) {
79 const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
80 const uint32_t A = SharpYuvGammaToLinear(a, bit_depth);
81 const uint32_t B = SharpYuvGammaToLinear(b, bit_depth);
82 const uint32_t C = SharpYuvGammaToLinear(c, bit_depth);
83 const uint32_t D = SharpYuvGammaToLinear(d, bit_depth);
84 return SharpYuvLinearToGamma((A + B + C + D + 2) >> 2, bit_depth);
85}
86
87static WEBP_INLINE void UpdateW(const fixed_y_t* src, fixed_y_t* dst, int w,
88 int rgb_bit_depth) {
89 const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
90 int i;
91 for (i = 0; i < w; ++i) {
92 const uint32_t R = SharpYuvGammaToLinear(src[0 * w + i], bit_depth);
93 const uint32_t G = SharpYuvGammaToLinear(src[1 * w + i], bit_depth);
94 const uint32_t B = SharpYuvGammaToLinear(src[2 * w + i], bit_depth);
95 const uint32_t Y = RGBToGray(R, G, B);
96 dst[i] = (fixed_y_t)SharpYuvLinearToGamma(Y, bit_depth);
97 }
98}
99
100static void UpdateChroma(const fixed_y_t* src1, const fixed_y_t* src2,
101 fixed_t* dst, int uv_w, int rgb_bit_depth) {
102 int i;
103 for (i = 0; i < uv_w; ++i) {
104 const int r =
105 ScaleDown(src1[0 * uv_w + 0], src1[0 * uv_w + 1], src2[0 * uv_w + 0],
106 src2[0 * uv_w + 1], rgb_bit_depth);
107 const int g =
108 ScaleDown(src1[2 * uv_w + 0], src1[2 * uv_w + 1], src2[2 * uv_w + 0],
109 src2[2 * uv_w + 1], rgb_bit_depth);
110 const int b =
111 ScaleDown(src1[4 * uv_w + 0], src1[4 * uv_w + 1], src2[4 * uv_w + 0],
112 src2[4 * uv_w + 1], rgb_bit_depth);
113 const int W = RGBToGray(r, g, b);
114 dst[0 * uv_w] = (fixed_t)(r - W);
115 dst[1 * uv_w] = (fixed_t)(g - W);
116 dst[2 * uv_w] = (fixed_t)(b - W);
117 dst += 1;
118 src1 += 2;
119 src2 += 2;
120 }
121}
122
123static void StoreGray(const fixed_y_t* rgb, fixed_y_t* y, int w) {
124 int i;
125 assert(w > 0);
126 for (i = 0; i < w; ++i) {
127 y[i] = RGBToGray(rgb[0 * w + i], rgb[1 * w + i], rgb[2 * w + i]);
128 }
129}
130
131//------------------------------------------------------------------------------
132
133static WEBP_INLINE fixed_y_t Filter2(int A, int B, int W0, int bit_depth) {
134 const int v0 = (A * 3 + B + 2) >> 2;
135 return clip_bit_depth(v0 + W0, bit_depth);
136}
137
138//------------------------------------------------------------------------------
139
140static WEBP_INLINE int Shift(int v, int shift) {
141 return (shift >= 0) ? (v << shift) : (v >> -shift);
142}
143
144static void ImportOneRow(const uint8_t* const r_ptr,
145 const uint8_t* const g_ptr,
146 const uint8_t* const b_ptr,
147 int rgb_step,
148 int rgb_bit_depth,
149 int pic_width,
150 fixed_y_t* const dst) {
151 // Convert the rgb_step from a number of bytes to a number of uint8_t or
152 // uint16_t values depending the bit depth.
153 const int step = (rgb_bit_depth > 8) ? rgb_step / 2 : rgb_step;
154 int i;
155 const int w = (pic_width + 1) & ~1;
156 for (i = 0; i < pic_width; ++i) {
157 const int off = i * step;
158 const int shift = GetPrecisionShift(rgb_bit_depth);
159 if (rgb_bit_depth == 8) {
160 dst[i + 0 * w] = Shift(r_ptr[off], shift);
161 dst[i + 1 * w] = Shift(g_ptr[off], shift);
162 dst[i + 2 * w] = Shift(b_ptr[off], shift);
163 } else {
164 dst[i + 0 * w] = Shift(((uint16_t*)r_ptr)[off], shift);
165 dst[i + 1 * w] = Shift(((uint16_t*)g_ptr)[off], shift);
166 dst[i + 2 * w] = Shift(((uint16_t*)b_ptr)[off], shift);
167 }
168 }
169 if (pic_width & 1) { // replicate rightmost pixel
170 dst[pic_width + 0 * w] = dst[pic_width + 0 * w - 1];
171 dst[pic_width + 1 * w] = dst[pic_width + 1 * w - 1];
172 dst[pic_width + 2 * w] = dst[pic_width + 2 * w - 1];
173 }
174}
175
176static void InterpolateTwoRows(const fixed_y_t* const best_y,
177 const fixed_t* prev_uv,
178 const fixed_t* cur_uv,
179 const fixed_t* next_uv,
180 int w,
181 fixed_y_t* out1,
182 fixed_y_t* out2,
183 int rgb_bit_depth) {
184 const int uv_w = w >> 1;
185 const int len = (w - 1) >> 1; // length to filter
186 int k = 3;
187 const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
188 while (k-- > 0) { // process each R/G/B segments in turn
189 // special boundary case for i==0
190 out1[0] = Filter2(cur_uv[0], prev_uv[0], best_y[0], bit_depth);
191 out2[0] = Filter2(cur_uv[0], next_uv[0], best_y[w], bit_depth);
192
193 SharpYuvFilterRow(cur_uv, prev_uv, len, best_y + 0 + 1, out1 + 1,
194 bit_depth);
195 SharpYuvFilterRow(cur_uv, next_uv, len, best_y + w + 1, out2 + 1,
196 bit_depth);
197
198 // special boundary case for i == w - 1 when w is even
199 if (!(w & 1)) {
200 out1[w - 1] = Filter2(cur_uv[uv_w - 1], prev_uv[uv_w - 1],
201 best_y[w - 1 + 0], bit_depth);
202 out2[w - 1] = Filter2(cur_uv[uv_w - 1], next_uv[uv_w - 1],
203 best_y[w - 1 + w], bit_depth);
204 }
205 out1 += w;
206 out2 += w;
207 prev_uv += uv_w;
208 cur_uv += uv_w;
209 next_uv += uv_w;
210 }
211}
212
213static WEBP_INLINE int RGBToYUVComponent(int r, int g, int b,
214 const int coeffs[4], int sfix) {
215 const int srounder = 1 << (YUV_FIX + sfix - 1);
216 const int luma = coeffs[0] * r + coeffs[1] * g + coeffs[2] * b +
217 coeffs[3] + srounder;
218 return (luma >> (YUV_FIX + sfix));
219}
220
221static int ConvertWRGBToYUV(const fixed_y_t* best_y, const fixed_t* best_uv,
222 uint8_t* y_ptr, int y_stride, uint8_t* u_ptr,
223 int u_stride, uint8_t* v_ptr, int v_stride,
224 int rgb_bit_depth,
225 int yuv_bit_depth, int width, int height,
226 const SharpYuvConversionMatrix* yuv_matrix) {
227 int i, j;
228 const fixed_t* const best_uv_base = best_uv;
229 const int w = (width + 1) & ~1;
230 const int h = (height + 1) & ~1;
231 const int uv_w = w >> 1;
232 const int uv_h = h >> 1;
233 const int sfix = GetPrecisionShift(rgb_bit_depth);
234 const int yuv_max = (1 << yuv_bit_depth) - 1;
235
236 for (best_uv = best_uv_base, j = 0; j < height; ++j) {
237 for (i = 0; i < width; ++i) {
238 const int off = (i >> 1);
239 const int W = best_y[i];
240 const int r = best_uv[off + 0 * uv_w] + W;
241 const int g = best_uv[off + 1 * uv_w] + W;
242 const int b = best_uv[off + 2 * uv_w] + W;
243 const int y = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_y, sfix);
244 if (yuv_bit_depth <= 8) {
245 y_ptr[i] = clip_8b(y);
246 } else {
247 ((uint16_t*)y_ptr)[i] = clip(y, yuv_max);
248 }
249 }
250 best_y += w;
251 best_uv += (j & 1) * 3 * uv_w;
252 y_ptr += y_stride;
253 }
254 for (best_uv = best_uv_base, j = 0; j < uv_h; ++j) {
255 for (i = 0; i < uv_w; ++i) {
256 const int off = i;
257 // Note r, g and b values here are off by W, but a constant offset on all
258 // 3 components doesn't change the value of u and v with a YCbCr matrix.
259 const int r = best_uv[off + 0 * uv_w];
260 const int g = best_uv[off + 1 * uv_w];
261 const int b = best_uv[off + 2 * uv_w];
262 const int u = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_u, sfix);
263 const int v = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_v, sfix);
264 if (yuv_bit_depth <= 8) {
265 u_ptr[i] = clip_8b(u);
266 v_ptr[i] = clip_8b(v);
267 } else {
268 ((uint16_t*)u_ptr)[i] = clip(u, yuv_max);
269 ((uint16_t*)v_ptr)[i] = clip(v, yuv_max);
270 }
271 }
272 best_uv += 3 * uv_w;
273 u_ptr += u_stride;
274 v_ptr += v_stride;
275 }
276 return 1;
277}
278
279//------------------------------------------------------------------------------
280// Main function
281
282static void* SafeMalloc(uint64_t nmemb, size_t size) {
283 const uint64_t total_size = nmemb * (uint64_t)size;
284 if (total_size != (size_t)total_size) return NULL;
285 return malloc((size_t)total_size);
286}
287
288#define SAFE_ALLOC(W, H, T) ((T*)SafeMalloc((W) * (H), sizeof(T)))
289
290static int DoSharpArgbToYuv(const uint8_t* r_ptr, const uint8_t* g_ptr,
291 const uint8_t* b_ptr, int rgb_step, int rgb_stride,
292 int rgb_bit_depth, uint8_t* y_ptr, int y_stride,
293 uint8_t* u_ptr, int u_stride, uint8_t* v_ptr,
294 int v_stride, int yuv_bit_depth, int width,
295 int height,
296 const SharpYuvConversionMatrix* yuv_matrix) {
297 // we expand the right/bottom border if needed
298 const int w = (width + 1) & ~1;
299 const int h = (height + 1) & ~1;
300 const int uv_w = w >> 1;
301 const int uv_h = h >> 1;
302 uint64_t prev_diff_y_sum = ~0;
303 int j, iter;
304
305 // TODO(skal): allocate one big memory chunk. But for now, it's easier
306 // for valgrind debugging to have several chunks.
307 fixed_y_t* const tmp_buffer = SAFE_ALLOC(w * 3, 2, fixed_y_t); // scratch
308 fixed_y_t* const best_y_base = SAFE_ALLOC(w, h, fixed_y_t);
309 fixed_y_t* const target_y_base = SAFE_ALLOC(w, h, fixed_y_t);
310 fixed_y_t* const best_rgb_y = SAFE_ALLOC(w, 2, fixed_y_t);
311 fixed_t* const best_uv_base = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t);
312 fixed_t* const target_uv_base = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t);
313 fixed_t* const best_rgb_uv = SAFE_ALLOC(uv_w * 3, 1, fixed_t);
314 fixed_y_t* best_y = best_y_base;
315 fixed_y_t* target_y = target_y_base;
316 fixed_t* best_uv = best_uv_base;
317 fixed_t* target_uv = target_uv_base;
318 const uint64_t diff_y_threshold = (uint64_t)(3.0 * w * h);
319 int ok;
320 assert(w > 0);
321 assert(h > 0);
322
323 if (best_y_base == NULL || best_uv_base == NULL ||
324 target_y_base == NULL || target_uv_base == NULL ||
325 best_rgb_y == NULL || best_rgb_uv == NULL ||
326 tmp_buffer == NULL) {
327 ok = 0;
328 goto End;
329 }
330
331 // Import RGB samples to W/RGB representation.
332 for (j = 0; j < height; j += 2) {
333 const int is_last_row = (j == height - 1);
334 fixed_y_t* const src1 = tmp_buffer + 0 * w;
335 fixed_y_t* const src2 = tmp_buffer + 3 * w;
336
337 // prepare two rows of input
338 ImportOneRow(r_ptr, g_ptr, b_ptr, rgb_step, rgb_bit_depth, width,
339 src1);
340 if (!is_last_row) {
341 ImportOneRow(r_ptr + rgb_stride, g_ptr + rgb_stride, b_ptr + rgb_stride,
342 rgb_step, rgb_bit_depth, width, src2);
343 } else {
344 memcpy(src2, src1, 3 * w * sizeof(*src2));
345 }
346 StoreGray(src1, best_y + 0, w);
347 StoreGray(src2, best_y + w, w);
348
349 UpdateW(src1, target_y, w, rgb_bit_depth);
350 UpdateW(src2, target_y + w, w, rgb_bit_depth);
351 UpdateChroma(src1, src2, target_uv, uv_w, rgb_bit_depth);
352 memcpy(best_uv, target_uv, 3 * uv_w * sizeof(*best_uv));
353 best_y += 2 * w;
354 best_uv += 3 * uv_w;
355 target_y += 2 * w;
356 target_uv += 3 * uv_w;
357 r_ptr += 2 * rgb_stride;
358 g_ptr += 2 * rgb_stride;
359 b_ptr += 2 * rgb_stride;
360 }
361
362 // Iterate and resolve clipping conflicts.
363 for (iter = 0; iter < kNumIterations; ++iter) {
364 const fixed_t* cur_uv = best_uv_base;
365 const fixed_t* prev_uv = best_uv_base;
366 uint64_t diff_y_sum = 0;
367
368 best_y = best_y_base;
369 best_uv = best_uv_base;
370 target_y = target_y_base;
371 target_uv = target_uv_base;
372 for (j = 0; j < h; j += 2) {
373 fixed_y_t* const src1 = tmp_buffer + 0 * w;
374 fixed_y_t* const src2 = tmp_buffer + 3 * w;
375 {
376 const fixed_t* const next_uv = cur_uv + ((j < h - 2) ? 3 * uv_w : 0);
377 InterpolateTwoRows(best_y, prev_uv, cur_uv, next_uv, w,
378 src1, src2, rgb_bit_depth);
379 prev_uv = cur_uv;
380 cur_uv = next_uv;
381 }
382
383 UpdateW(src1, best_rgb_y + 0 * w, w, rgb_bit_depth);
384 UpdateW(src2, best_rgb_y + 1 * w, w, rgb_bit_depth);
385 UpdateChroma(src1, src2, best_rgb_uv, uv_w, rgb_bit_depth);
386
387 // update two rows of Y and one row of RGB
388 diff_y_sum +=
389 SharpYuvUpdateY(target_y, best_rgb_y, best_y, 2 * w,
390 rgb_bit_depth + GetPrecisionShift(rgb_bit_depth));
391 SharpYuvUpdateRGB(target_uv, best_rgb_uv, best_uv, 3 * uv_w);
392
393 best_y += 2 * w;
394 best_uv += 3 * uv_w;
395 target_y += 2 * w;
396 target_uv += 3 * uv_w;
397 }
398 // test exit condition
399 if (iter > 0) {
400 if (diff_y_sum < diff_y_threshold) break;
401 if (diff_y_sum > prev_diff_y_sum) break;
402 }
403 prev_diff_y_sum = diff_y_sum;
404 }
405
406 // final reconstruction
407 ok = ConvertWRGBToYUV(best_y_base, best_uv_base, y_ptr, y_stride, u_ptr,
408 u_stride, v_ptr, v_stride, rgb_bit_depth, yuv_bit_depth,
409 width, height, yuv_matrix);
410
411 End:
412 free(best_y_base);
413 free(best_uv_base);
414 free(target_y_base);
415 free(target_uv_base);
416 free(best_rgb_y);
417 free(best_rgb_uv);
418 free(tmp_buffer);
419 return ok;
420}
421#undef SAFE_ALLOC
422
423#if defined(WEBP_USE_THREAD) && !defined(_WIN32)
424#include <pthread.h> // NOLINT
425
426#define LOCK_ACCESS \
427 static pthread_mutex_t sharpyuv_lock = PTHREAD_MUTEX_INITIALIZER; \
428 if (pthread_mutex_lock(&sharpyuv_lock)) return
429#define UNLOCK_ACCESS_AND_RETURN \
430 do { \
431 (void)pthread_mutex_unlock(&sharpyuv_lock); \
432 return; \
433 } while (0)
434#else // !(defined(WEBP_USE_THREAD) && !defined(_WIN32))
435#define LOCK_ACCESS do {} while (0)
436#define UNLOCK_ACCESS_AND_RETURN return
437#endif // defined(WEBP_USE_THREAD) && !defined(_WIN32)
438
439// Hidden exported init function.
440// By default SharpYuvConvert calls it with SharpYuvGetCPUInfo. If needed,
441// users can declare it as extern and call it with an alternate VP8CPUInfo
442// function.
443extern VP8CPUInfo SharpYuvGetCPUInfo;
444SHARPYUV_EXTERN void SharpYuvInit(VP8CPUInfo cpu_info_func);
445void SharpYuvInit(VP8CPUInfo cpu_info_func) {
446 static volatile VP8CPUInfo sharpyuv_last_cpuinfo_used =
447 (VP8CPUInfo)&sharpyuv_last_cpuinfo_used;
448 LOCK_ACCESS;
449 // Only update SharpYuvGetCPUInfo when called from external code to avoid a
450 // race on reading the value in SharpYuvConvert().
451 if (cpu_info_func != (VP8CPUInfo)&SharpYuvGetCPUInfo) {
452 SharpYuvGetCPUInfo = cpu_info_func;
453 }
454 if (sharpyuv_last_cpuinfo_used == SharpYuvGetCPUInfo) {
455 UNLOCK_ACCESS_AND_RETURN;
456 }
457
458 SharpYuvInitDsp();
459 SharpYuvInitGammaTables();
460
461 sharpyuv_last_cpuinfo_used = SharpYuvGetCPUInfo;
462 UNLOCK_ACCESS_AND_RETURN;
463}
464
465int SharpYuvConvert(const void* r_ptr, const void* g_ptr,
466 const void* b_ptr, int rgb_step, int rgb_stride,
467 int rgb_bit_depth, void* y_ptr, int y_stride,
468 void* u_ptr, int u_stride, void* v_ptr,
469 int v_stride, int yuv_bit_depth, int width,
470 int height, const SharpYuvConversionMatrix* yuv_matrix) {
471 SharpYuvConversionMatrix scaled_matrix;
472 const int rgb_max = (1 << rgb_bit_depth) - 1;
473 const int rgb_round = 1 << (rgb_bit_depth - 1);
474 const int yuv_max = (1 << yuv_bit_depth) - 1;
475 const int sfix = GetPrecisionShift(rgb_bit_depth);
476
477 if (width < 1 || height < 1 || width == INT_MAX || height == INT_MAX ||
478 r_ptr == NULL || g_ptr == NULL || b_ptr == NULL || y_ptr == NULL ||
479 u_ptr == NULL || v_ptr == NULL) {
480 return 0;
481 }
482 if (rgb_bit_depth != 8 && rgb_bit_depth != 10 && rgb_bit_depth != 12 &&
483 rgb_bit_depth != 16) {
484 return 0;
485 }
486 if (yuv_bit_depth != 8 && yuv_bit_depth != 10 && yuv_bit_depth != 12) {
487 return 0;
488 }
489 if (rgb_bit_depth > 8 && (rgb_step % 2 != 0 || rgb_stride %2 != 0)) {
490 // Step/stride should be even for uint16_t buffers.
491 return 0;
492 }
493 if (yuv_bit_depth > 8 &&
494 (y_stride % 2 != 0 || u_stride % 2 != 0 || v_stride % 2 != 0)) {
495 // Stride should be even for uint16_t buffers.
496 return 0;
497 }
498 // The address of the function pointer is used to avoid a read race.
499 SharpYuvInit((VP8CPUInfo)&SharpYuvGetCPUInfo);
500
501 // Add scaling factor to go from rgb_bit_depth to yuv_bit_depth, to the
502 // rgb->yuv conversion matrix.
503 if (rgb_bit_depth == yuv_bit_depth) {
504 memcpy(&scaled_matrix, yuv_matrix, sizeof(scaled_matrix));
505 } else {
506 int i;
507 for (i = 0; i < 3; ++i) {
508 scaled_matrix.rgb_to_y[i] =
509 (yuv_matrix->rgb_to_y[i] * yuv_max + rgb_round) / rgb_max;
510 scaled_matrix.rgb_to_u[i] =
511 (yuv_matrix->rgb_to_u[i] * yuv_max + rgb_round) / rgb_max;
512 scaled_matrix.rgb_to_v[i] =
513 (yuv_matrix->rgb_to_v[i] * yuv_max + rgb_round) / rgb_max;
514 }
515 }
516 // Also incorporate precision change scaling.
517 scaled_matrix.rgb_to_y[3] = Shift(yuv_matrix->rgb_to_y[3], sfix);
518 scaled_matrix.rgb_to_u[3] = Shift(yuv_matrix->rgb_to_u[3], sfix);
519 scaled_matrix.rgb_to_v[3] = Shift(yuv_matrix->rgb_to_v[3], sfix);
520
521 return DoSharpArgbToYuv(r_ptr, g_ptr, b_ptr, rgb_step, rgb_stride,
522 rgb_bit_depth, y_ptr, y_stride, u_ptr, u_stride,
523 v_ptr, v_stride, yuv_bit_depth, width, height,
524 &scaled_matrix);
525}
526
527//------------------------------------------------------------------------------
528