media/base/yuv_convert.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This webpage shows layout of YV12 and other YUV formats
   6 // http://www.fourcc.org/yuv.php
   7 // The actual conversion is best described here
   8 // http://en.wikipedia.org/wiki/YUV
   9 // An article on optimizing YUV conversion using tables instead of multiplies
  10 // http://lestourtereaux.free.fr/papers/data/yuvrgb.pdf
  11 //
  12 // YV12 is a full plane of Y and a half height, half width chroma planes
  13 // YV16 is a full plane of Y and a full height, half width chroma planes
  14 //
  15 // ARGB pixel format is output, which on little endian is stored as BGRA.
  16 // The alpha is set to 255, allowing the application to use RGBA or RGB32.
  17
  18 #include "media/base/yuv_convert.h"
  19
  20 #include "base/cpu.h"
  21 #include "base/logging.h"
  22 #include "base/memory/scoped_ptr.h"
  23 #include "build/build_config.h"
  24 #include "media/base/simd/convert_rgb_to_yuv.h"
  25 #include "media/base/simd/convert_yuv_to_rgb.h"
  26 #include "media/base/simd/filter_yuv.h"
  27
  28 #if defined(ARCH_CPU_X86_FAMILY)
  29 #if defined(COMPILER_MSVC)
  30 #include <intrin.h>
  31 #else
  32 #include <mmintrin.h>
  33 #endif
  34 #endif
  35
  36 // Assembly functions are declared without namespace.
  37 extern "C" { void EmptyRegisterState_MMX(); }  // extern "C"
  38
  39 namespace media {
  40
  41 typedef void (*FilterYUVRowsProc)(uint8*, const uint8*, const uint8*, int, int);
  42
  43 typedef void (*ConvertRGBToYUVProc)(const uint8*,
  44                                     uint8*,
  45                                     uint8*,
  46                                     uint8*,
  47                                     int,
  48                                     int,
  49                                     int,
  50                                     int,
  51                                     int);
  52
  53 typedef void (*ConvertYUVToRGB32Proc)(const uint8*,
  54                                       const uint8*,
  55                                       const uint8*,
  56                                       uint8*,
  57                                       int,
  58                                       int,
  59                                       int,
  60                                       int,
  61                                       int,
  62                                       YUVType);
  63
  64 typedef void (*ConvertYUVAToARGBProc)(const uint8*,
  65                                       const uint8*,
  66                                       const uint8*,
  67                                       const uint8*,
  68                                       uint8*,
  69                                       int,
  70                                       int,
  71                                       int,
  72                                       int,
  73                                       int,
  74                                       int,
  75                                       YUVType);
  76
  77 typedef void (*ConvertYUVToRGB32RowProc)(const uint8*,
  78                                          const uint8*,
  79                                          const uint8*,
  80                                          uint8*,
  81                                          ptrdiff_t);
  82
  83 typedef void (*ConvertYUVAToARGBRowProc)(const uint8*,
  84                                          const uint8*,
  85                                          const uint8*,
  86                                          const uint8*,
  87                                          uint8*,
  88                                          ptrdiff_t);
  89
  90 typedef void (*ScaleYUVToRGB32RowProc)(const uint8*,
  91                                        const uint8*,
  92                                        const uint8*,
  93                                        uint8*,
  94                                        ptrdiff_t,
  95                                        ptrdiff_t);
  96
  97 static FilterYUVRowsProc g_filter_yuv_rows_proc_ = NULL;
  98 static ConvertYUVToRGB32RowProc g_convert_yuv_to_rgb32_row_proc_ = NULL;
  99 static ScaleYUVToRGB32RowProc g_scale_yuv_to_rgb32_row_proc_ = NULL;
 100 static ScaleYUVToRGB32RowProc g_linear_scale_yuv_to_rgb32_row_proc_ = NULL;
 101 static ConvertRGBToYUVProc g_convert_rgb32_to_yuv_proc_ = NULL;
 102 static ConvertRGBToYUVProc g_convert_rgb24_to_yuv_proc_ = NULL;
 103 static ConvertYUVToRGB32Proc g_convert_yuv_to_rgb32_proc_ = NULL;
 104 static ConvertYUVAToARGBProc g_convert_yuva_to_argb_proc_ = NULL;
 105
 106 // Empty SIMD registers state after using them.
 107 void EmptyRegisterStateStub() {}
 108 #if defined(MEDIA_MMX_INTRINSICS_AVAILABLE)
 109 void EmptyRegisterStateIntrinsic() { _mm_empty(); }
 110 #endif
 111 typedef void (*EmptyRegisterStateProc)();
 112 static EmptyRegisterStateProc g_empty_register_state_proc_ = NULL;
 113
 114 void InitializeCPUSpecificYUVConversions() {
 115   CHECK(!g_filter_yuv_rows_proc_);
 116   CHECK(!g_convert_yuv_to_rgb32_row_proc_);
 117   CHECK(!g_scale_yuv_to_rgb32_row_proc_);
 118   CHECK(!g_linear_scale_yuv_to_rgb32_row_proc_);
 119   CHECK(!g_convert_rgb32_to_yuv_proc_);
 120   CHECK(!g_convert_rgb24_to_yuv_proc_);
 121   CHECK(!g_convert_yuv_to_rgb32_proc_);
 122   CHECK(!g_convert_yuva_to_argb_proc_);
 123   CHECK(!g_empty_register_state_proc_);
 124
 125   g_filter_yuv_rows_proc_ = FilterYUVRows_C;
 126   g_convert_yuv_to_rgb32_row_proc_ = ConvertYUVToRGB32Row_C;
 127   g_scale_yuv_to_rgb32_row_proc_ = ScaleYUVToRGB32Row_C;
 128   g_linear_scale_yuv_to_rgb32_row_proc_ = LinearScaleYUVToRGB32Row_C;
 129   g_convert_rgb32_to_yuv_proc_ = ConvertRGB32ToYUV_C;
 130   g_convert_rgb24_to_yuv_proc_ = ConvertRGB24ToYUV_C;
 131   g_convert_yuv_to_rgb32_proc_ = ConvertYUVToRGB32_C;
 132   g_convert_yuva_to_argb_proc_ = ConvertYUVAToARGB_C;
 133   g_empty_register_state_proc_ = EmptyRegisterStateStub;
 134
 135 #if defined(ARCH_CPU_X86_FAMILY)
 136   base::CPU cpu;
 137   if (cpu.has_mmx()) {
 138     g_convert_yuv_to_rgb32_row_proc_ = ConvertYUVToRGB32Row_MMX;
 139     g_scale_yuv_to_rgb32_row_proc_ = ScaleYUVToRGB32Row_MMX;
 140     g_convert_yuv_to_rgb32_proc_ = ConvertYUVToRGB32_MMX;
 141     g_convert_yuva_to_argb_proc_ = ConvertYUVAToARGB_MMX;
 142     g_linear_scale_yuv_to_rgb32_row_proc_ = LinearScaleYUVToRGB32Row_MMX;
 143
 144 #if defined(MEDIA_MMX_INTRINSICS_AVAILABLE)
 145     g_filter_yuv_rows_proc_ = FilterYUVRows_MMX;
 146     g_empty_register_state_proc_ = EmptyRegisterStateIntrinsic;
 147 #else
 148     g_empty_register_state_proc_ = EmptyRegisterState_MMX;
 149 #endif
 150   }
 151
 152   if (cpu.has_sse()) {
 153     g_convert_yuv_to_rgb32_row_proc_ = ConvertYUVToRGB32Row_SSE;
 154     g_scale_yuv_to_rgb32_row_proc_ = ScaleYUVToRGB32Row_SSE;
 155     g_linear_scale_yuv_to_rgb32_row_proc_ = LinearScaleYUVToRGB32Row_SSE;
 156     g_convert_yuv_to_rgb32_proc_ = ConvertYUVToRGB32_SSE;
 157   }
 158
 159   if (cpu.has_sse2()) {
 160     g_filter_yuv_rows_proc_ = FilterYUVRows_SSE2;
 161     g_convert_rgb32_to_yuv_proc_ = ConvertRGB32ToYUV_SSE2;
 162
 163 #if defined(ARCH_CPU_X86_64)
 164     g_scale_yuv_to_rgb32_row_proc_ = ScaleYUVToRGB32Row_SSE2_X64;
 165
 166     // Technically this should be in the MMX section, but MSVC will optimize out
 167     // the export of LinearScaleYUVToRGB32Row_MMX, which is required by the unit
 168     // tests, if that decision can be made at compile time.  Since all X64 CPUs
 169     // have SSE2, we can hack around this by making the selection here.
 170     g_linear_scale_yuv_to_rgb32_row_proc_ = LinearScaleYUVToRGB32Row_MMX_X64;
 171 #endif
 172   }
 173
 174   if (cpu.has_ssse3()) {
 175     g_convert_rgb24_to_yuv_proc_ = &ConvertRGB24ToYUV_SSSE3;
 176
 177     // TODO(hclam): Add ConvertRGB32ToYUV_SSSE3 when the cyan problem is solved.
 178     // See: crbug.com/100462
 179   }
 180 #endif
 181 }
 182
 183 // Empty SIMD registers state after using them.
 184 void EmptyRegisterState() { g_empty_register_state_proc_(); }
 185
 186 // 16.16 fixed point arithmetic
 187 const int kFractionBits = 16;
 188 const int kFractionMax = 1 << kFractionBits;
 189 const int kFractionMask = ((1 << kFractionBits) - 1);
 190
 191 // Scale a frame of YUV to 32 bit ARGB.
 192 void ScaleYUVToRGB32(const uint8* y_buf,
 193                      const uint8* u_buf,
 194                      const uint8* v_buf,
 195                      uint8* rgb_buf,
 196                      int source_width,
 197                      int source_height,
 198                      int width,
 199                      int height,
 200                      int y_pitch,
 201                      int uv_pitch,
 202                      int rgb_pitch,
 203                      YUVType yuv_type,
 204                      Rotate view_rotate,
 205                      ScaleFilter filter) {
 206   // Handle zero sized sources and destinations.
 207   if ((yuv_type == YV12 && (source_width < 2 || source_height < 2)) ||
 208       (yuv_type == YV16 && (source_width < 2 || source_height < 1)) ||
 209       width == 0 || height == 0)
 210     return;
 211
 212   // 4096 allows 3 buffers to fit in 12k.
 213   // Helps performance on CPU with 16K L1 cache.
 214   // Large enough for 3830x2160 and 30" displays which are 2560x1600.
 215   const int kFilterBufferSize = 4096;
 216   // Disable filtering if the screen is too big (to avoid buffer overflows).
 217   // This should never happen to regular users: they don't have monitors
 218   // wider than 4096 pixels.
 219   // TODO(fbarchard): Allow rotated videos to filter.
 220   if (source_width > kFilterBufferSize || view_rotate)
 221     filter = FILTER_NONE;
 222
 223   unsigned int y_shift = yuv_type;
 224   // Diagram showing origin and direction of source sampling.
 225   // ->0   4<-
 226   // 7       3
 227   //
 228   // 6       5
 229   // ->1   2<-
 230   // Rotations that start at right side of image.
 231   if ((view_rotate == ROTATE_180) || (view_rotate == ROTATE_270) ||
 232       (view_rotate == MIRROR_ROTATE_0) || (view_rotate == MIRROR_ROTATE_90)) {
 233     y_buf += source_width - 1;
 234     u_buf += source_width / 2 - 1;
 235     v_buf += source_width / 2 - 1;
 236     source_width = -source_width;
 237   }
 238   // Rotations that start at bottom of image.
 239   if ((view_rotate == ROTATE_90) || (view_rotate == ROTATE_180) ||
 240       (view_rotate == MIRROR_ROTATE_90) || (view_rotate == MIRROR_ROTATE_180)) {
 241     y_buf += (source_height - 1) * y_pitch;
 242     u_buf += ((source_height >> y_shift) - 1) * uv_pitch;
 243     v_buf += ((source_height >> y_shift) - 1) * uv_pitch;
 244     source_height = -source_height;
 245   }
 246
 247   int source_dx = source_width * kFractionMax / width;
 248
 249   if ((view_rotate == ROTATE_90) || (view_rotate == ROTATE_270)) {
 250     int tmp = height;
 251     height = width;
 252     width = tmp;
 253     tmp = source_height;
 254     source_height = source_width;
 255     source_width = tmp;
 256     int source_dy = source_height * kFractionMax / height;
 257     source_dx = ((source_dy >> kFractionBits) * y_pitch) << kFractionBits;
 258     if (view_rotate == ROTATE_90) {
 259       y_pitch = -1;
 260       uv_pitch = -1;
 261       source_height = -source_height;
 262     } else {
 263       y_pitch = 1;
 264       uv_pitch = 1;
 265     }
 266   }
 267
 268   // Need padding because FilterRows() will write 1 to 16 extra pixels
 269   // after the end for SSE2 version.
 270   uint8 yuvbuf[16 + kFilterBufferSize * 3 + 16];
 271   uint8* ybuf =
 272       reinterpret_cast<uint8*>(reinterpret_cast<uintptr_t>(yuvbuf + 15) & ~15);
 273   uint8* ubuf = ybuf + kFilterBufferSize;
 274   uint8* vbuf = ubuf + kFilterBufferSize;
 275
 276   // TODO(fbarchard): Fixed point math is off by 1 on negatives.
 277
 278   // We take a y-coordinate in [0,1] space in the source image space, and
 279   // transform to a y-coordinate in [0,1] space in the destination image space.
 280   // Note that the coordinate endpoints lie on pixel boundaries, not on pixel
 281   // centers: e.g. a two-pixel-high image will have pixel centers at 0.25 and
 282   // 0.75.  The formula is as follows (in fixed-point arithmetic):
 283   //   y_dst = dst_height * ((y_src + 0.5) / src_height)
 284   //   dst_pixel = clamp([0, dst_height - 1], floor(y_dst - 0.5))
 285   // Implement this here as an accumulator + delta, to avoid expensive math
 286   // in the loop.
 287   int source_y_subpixel_accum =
 288       ((kFractionMax / 2) * source_height) / height - (kFractionMax / 2);
 289   int source_y_subpixel_delta = ((1 << kFractionBits) * source_height) / height;
 290
 291   // TODO(fbarchard): Split this into separate function for better efficiency.
 292   for (int y = 0; y < height; ++y) {
 293     uint8* dest_pixel = rgb_buf + y * rgb_pitch;
 294     int source_y_subpixel = source_y_subpixel_accum;
 295     source_y_subpixel_accum += source_y_subpixel_delta;
 296     if (source_y_subpixel < 0)
 297       source_y_subpixel = 0;
 298     else if (source_y_subpixel > ((source_height - 1) << kFractionBits))
 299       source_y_subpixel = (source_height - 1) << kFractionBits;
 300
 301     const uint8* y_ptr = NULL;
 302     const uint8* u_ptr = NULL;
 303     const uint8* v_ptr = NULL;
 304     // Apply vertical filtering if necessary.
 305     // TODO(fbarchard): Remove memcpy when not necessary.
 306     if (filter & media::FILTER_BILINEAR_V) {
 307       int source_y = source_y_subpixel >> kFractionBits;
 308       y_ptr = y_buf + source_y * y_pitch;
 309       u_ptr = u_buf + (source_y >> y_shift) * uv_pitch;
 310       v_ptr = v_buf + (source_y >> y_shift) * uv_pitch;
 311
 312       // Vertical scaler uses 16.8 fixed point.
 313       int source_y_fraction = (source_y_subpixel & kFractionMask) >> 8;
 314       if (source_y_fraction != 0) {
 315         g_filter_yuv_rows_proc_(
 316             ybuf, y_ptr, y_ptr + y_pitch, source_width, source_y_fraction);
 317       } else {
 318         memcpy(ybuf, y_ptr, source_width);
 319       }
 320       y_ptr = ybuf;
 321       ybuf[source_width] = ybuf[source_width - 1];
 322
 323       int uv_source_width = (source_width + 1) / 2;
 324       int source_uv_fraction;
 325
 326       // For formats with half-height UV planes, each even-numbered pixel row
 327       // should not interpolate, since the next row to interpolate from should
 328       // be a duplicate of the current row.
 329       if (y_shift && (source_y & 0x1) == 0)
 330         source_uv_fraction = 0;
 331       else
 332         source_uv_fraction = source_y_fraction;
 333
 334       if (source_uv_fraction != 0) {
 335         g_filter_yuv_rows_proc_(
 336             ubuf, u_ptr, u_ptr + uv_pitch, uv_source_width, source_uv_fraction);
 337         g_filter_yuv_rows_proc_(
 338             vbuf, v_ptr, v_ptr + uv_pitch, uv_source_width, source_uv_fraction);
 339       } else {
 340         memcpy(ubuf, u_ptr, uv_source_width);
 341         memcpy(vbuf, v_ptr, uv_source_width);
 342       }
 343       u_ptr = ubuf;
 344       v_ptr = vbuf;
 345       ubuf[uv_source_width] = ubuf[uv_source_width - 1];
 346       vbuf[uv_source_width] = vbuf[uv_source_width - 1];
 347     } else {
 348       // Offset by 1/2 pixel for center sampling.
 349       int source_y = (source_y_subpixel + (kFractionMax / 2)) >> kFractionBits;
 350       y_ptr = y_buf + source_y * y_pitch;
 351       u_ptr = u_buf + (source_y >> y_shift) * uv_pitch;
 352       v_ptr = v_buf + (source_y >> y_shift) * uv_pitch;
 353     }
 354     if (source_dx == kFractionMax) {  // Not scaled
 355       g_convert_yuv_to_rgb32_row_proc_(y_ptr, u_ptr, v_ptr, dest_pixel, width);
 356     } else {
 357       if (filter & FILTER_BILINEAR_H) {
 358         g_linear_scale_yuv_to_rgb32_row_proc_(
 359             y_ptr, u_ptr, v_ptr, dest_pixel, width, source_dx);
 360       } else {
 361         g_scale_yuv_to_rgb32_row_proc_(
 362             y_ptr, u_ptr, v_ptr, dest_pixel, width, source_dx);
 363       }
 364     }
 365   }
 366
 367   g_empty_register_state_proc_();
 368 }
 369
 370 // Scale a frame of YV12 to 32 bit ARGB for a specific rectangle.
 371 void ScaleYUVToRGB32WithRect(const uint8* y_buf,
 372                              const uint8* u_buf,
 373                              const uint8* v_buf,
 374                              uint8* rgb_buf,
 375                              int source_width,
 376                              int source_height,
 377                              int dest_width,
 378                              int dest_height,
 379                              int dest_rect_left,
 380                              int dest_rect_top,
 381                              int dest_rect_right,
 382                              int dest_rect_bottom,
 383                              int y_pitch,
 384                              int uv_pitch,
 385                              int rgb_pitch) {
 386   // This routine doesn't currently support up-scaling.
 387   CHECK_LE(dest_width, source_width);
 388   CHECK_LE(dest_height, source_height);
 389
 390   // Sanity-check the destination rectangle.
 391   DCHECK(dest_rect_left >= 0 && dest_rect_right <= dest_width);
 392   DCHECK(dest_rect_top >= 0 && dest_rect_bottom <= dest_height);
 393   DCHECK(dest_rect_right > dest_rect_left);
 394   DCHECK(dest_rect_bottom > dest_rect_top);
 395
 396   // Fixed-point value of vertical and horizontal scale down factor.
 397   // Values are in the format 16.16.
 398   int y_step = kFractionMax * source_height / dest_height;
 399   int x_step = kFractionMax * source_width / dest_width;
 400
 401   // Determine the coordinates of the rectangle in 16.16 coords.
 402   // NB: Our origin is the *center* of the top/left pixel, NOT its top/left.
 403   // If we're down-scaling by more than a factor of two, we start with a 50%
 404   // fraction to avoid degenerating to point-sampling - we should really just
 405   // fix the fraction at 50% for all pixels in that case.
 406   int source_left = dest_rect_left * x_step;
 407   int source_right = (dest_rect_right - 1) * x_step;
 408   if (x_step < kFractionMax * 2) {
 409     source_left += ((x_step - kFractionMax) / 2);
 410     source_right += ((x_step - kFractionMax) / 2);
 411   } else {
 412     source_left += kFractionMax / 2;
 413     source_right += kFractionMax / 2;
 414   }
 415   int source_top = dest_rect_top * y_step;
 416   if (y_step < kFractionMax * 2) {
 417     source_top += ((y_step - kFractionMax) / 2);
 418   } else {
 419     source_top += kFractionMax / 2;
 420   }
 421
 422   // Determine the parts of the Y, U and V buffers to interpolate.
 423   int source_y_left = source_left >> kFractionBits;
 424   int source_y_right =
 425       std::min((source_right >> kFractionBits) + 2, source_width + 1);
 426
 427   int source_uv_left = source_y_left / 2;
 428   int source_uv_right = std::min((source_right >> (kFractionBits + 1)) + 2,
 429                                  (source_width + 1) / 2);
 430
 431   int source_y_width = source_y_right - source_y_left;
 432   int source_uv_width = source_uv_right - source_uv_left;
 433
 434   // Determine number of pixels in each output row.
 435   int dest_rect_width = dest_rect_right - dest_rect_left;
 436
 437   // Intermediate buffer for vertical interpolation.
 438   // 4096 bytes allows 3 buffers to fit in 12k, which fits in a 16K L1 cache,
 439   // and is bigger than most users will generally need.
 440   // The buffer is 16-byte aligned and padded with 16 extra bytes; some of the
 441   // FilterYUVRowProcs have alignment requirements, and the SSE version can
 442   // write up to 16 bytes past the end of the buffer.
 443   const int kFilterBufferSize = 4096;
 444   const bool kAvoidUsingOptimizedFilter = source_width > kFilterBufferSize;
 445   uint8 yuv_temp[16 + kFilterBufferSize * 3 + 16];
 446   uint8* y_temp = reinterpret_cast<uint8*>(
 447       reinterpret_cast<uintptr_t>(yuv_temp + 15) & ~15);
 448   uint8* u_temp = y_temp + kFilterBufferSize;
 449   uint8* v_temp = u_temp + kFilterBufferSize;
 450
 451   // Move to the top-left pixel of output.
 452   rgb_buf += dest_rect_top * rgb_pitch;
 453   rgb_buf += dest_rect_left * 4;
 454
 455   // For each destination row perform interpolation and color space
 456   // conversion to produce the output.
 457   for (int row = dest_rect_top; row < dest_rect_bottom; ++row) {
 458     // Round the fixed-point y position to get the current row.
 459     int source_row = source_top >> kFractionBits;
 460     int source_uv_row = source_row / 2;
 461     DCHECK(source_row < source_height);
 462
 463     // Locate the first row for each plane for interpolation.
 464     const uint8* y0_ptr = y_buf + y_pitch * source_row + source_y_left;
 465     const uint8* u0_ptr = u_buf + uv_pitch * source_uv_row + source_uv_left;
 466     const uint8* v0_ptr = v_buf + uv_pitch * source_uv_row + source_uv_left;
 467     const uint8* y1_ptr = NULL;
 468     const uint8* u1_ptr = NULL;
 469     const uint8* v1_ptr = NULL;
 470
 471     // Locate the second row for interpolation, being careful not to overrun.
 472     if (source_row + 1 >= source_height) {
 473       y1_ptr = y0_ptr;
 474     } else {
 475       y1_ptr = y0_ptr + y_pitch;
 476     }
 477     if (source_uv_row + 1 >= (source_height + 1) / 2) {
 478       u1_ptr = u0_ptr;
 479       v1_ptr = v0_ptr;
 480     } else {
 481       u1_ptr = u0_ptr + uv_pitch;
 482       v1_ptr = v0_ptr + uv_pitch;
 483     }
 484
 485     if (!kAvoidUsingOptimizedFilter) {
 486       // Vertical scaler uses 16.8 fixed point.
 487       int fraction = (source_top & kFractionMask) >> 8;
 488       g_filter_yuv_rows_proc_(
 489           y_temp + source_y_left, y0_ptr, y1_ptr, source_y_width, fraction);
 490       g_filter_yuv_rows_proc_(
 491           u_temp + source_uv_left, u0_ptr, u1_ptr, source_uv_width, fraction);
 492       g_filter_yuv_rows_proc_(
 493           v_temp + source_uv_left, v0_ptr, v1_ptr, source_uv_width, fraction);
 494
 495       // Perform horizontal interpolation and color space conversion.
 496       // TODO(hclam): Use the MMX version after more testing.
 497       LinearScaleYUVToRGB32RowWithRange_C(y_temp,
 498                                           u_temp,
 499                                           v_temp,
 500                                           rgb_buf,
 501                                           dest_rect_width,
 502                                           source_left,
 503                                           x_step);
 504     } else {
 505       // If the frame is too large then we linear scale a single row.
 506       LinearScaleYUVToRGB32RowWithRange_C(y0_ptr,
 507                                           u0_ptr,
 508                                           v0_ptr,
 509                                           rgb_buf,
 510                                           dest_rect_width,
 511                                           source_left,
 512                                           x_step);
 513     }
 514
 515     // Advance vertically in the source and destination image.
 516     source_top += y_step;
 517     rgb_buf += rgb_pitch;
 518   }
 519
 520   g_empty_register_state_proc_();
 521 }
 522
 523 void ConvertRGB32ToYUV(const uint8* rgbframe,
 524                        uint8* yplane,
 525                        uint8* uplane,
 526                        uint8* vplane,
 527                        int width,
 528                        int height,
 529                        int rgbstride,
 530                        int ystride,
 531                        int uvstride) {
 532   g_convert_rgb32_to_yuv_proc_(rgbframe,
 533                                yplane,
 534                                uplane,
 535                                vplane,
 536                                width,
 537                                height,
 538                                rgbstride,
 539                                ystride,
 540                                uvstride);
 541 }
 542
 543 void ConvertRGB24ToYUV(const uint8* rgbframe,
 544                        uint8* yplane,
 545                        uint8* uplane,
 546                        uint8* vplane,
 547                        int width,
 548                        int height,
 549                        int rgbstride,
 550                        int ystride,
 551                        int uvstride) {
 552   g_convert_rgb24_to_yuv_proc_(rgbframe,
 553                                yplane,
 554                                uplane,
 555                                vplane,
 556                                width,
 557                                height,
 558                                rgbstride,
 559                                ystride,
 560                                uvstride);
 561 }
 562
 563 void ConvertYUY2ToYUV(const uint8* src,
 564                       uint8* yplane,
 565                       uint8* uplane,
 566                       uint8* vplane,
 567                       int width,
 568                       int height) {
 569   for (int i = 0; i < height / 2; ++i) {
 570     for (int j = 0; j < (width / 2); ++j) {
 571       yplane[0] = src[0];
 572       *uplane = src[1];
 573       yplane[1] = src[2];
 574       *vplane = src[3];
 575       src += 4;
 576       yplane += 2;
 577       uplane++;
 578       vplane++;
 579     }
 580     for (int j = 0; j < (width / 2); ++j) {
 581       yplane[0] = src[0];
 582       yplane[1] = src[2];
 583       src += 4;
 584       yplane += 2;
 585     }
 586   }
 587 }
 588
 589 void ConvertNV21ToYUV(const uint8* src,
 590                       uint8* yplane,
 591                       uint8* uplane,
 592                       uint8* vplane,
 593                       int width,
 594                       int height) {
 595   int y_plane_size = width * height;
 596   memcpy(yplane, src, y_plane_size);
 597
 598   src += y_plane_size;
 599   int u_plane_size = y_plane_size >> 2;
 600   for (int i = 0; i < u_plane_size; ++i) {
 601     *vplane++ = *src++;
 602     *uplane++ = *src++;
 603   }
 604 }
 605
 606 void ConvertYUVToRGB32(const uint8* yplane,
 607                        const uint8* uplane,
 608                        const uint8* vplane,
 609                        uint8* rgbframe,
 610                        int width,
 611                        int height,
 612                        int ystride,
 613                        int uvstride,
 614                        int rgbstride,
 615                        YUVType yuv_type) {
 616   g_convert_yuv_to_rgb32_proc_(yplane,
 617                                uplane,
 618                                vplane,
 619                                rgbframe,
 620                                width,
 621                                height,
 622                                ystride,
 623                                uvstride,
 624                                rgbstride,
 625                                yuv_type);
 626 }
 627
 628 void ConvertYUVAToARGB(const uint8* yplane,
 629                        const uint8* uplane,
 630                        const uint8* vplane,
 631                        const uint8* aplane,
 632                        uint8* rgbframe,
 633                        int width,
 634                        int height,
 635                        int ystride,
 636                        int uvstride,
 637                        int astride,
 638                        int rgbstride,
 639                        YUVType yuv_type) {
 640   g_convert_yuva_to_argb_proc_(yplane,
 641                                uplane,
 642                                vplane,
 643                                aplane,
 644                                rgbframe,
 645                                width,
 646                                height,
 647                                ystride,
 648                                uvstride,
 649                                astride,
 650                                rgbstride,
 651                                yuv_type);
 652 }
 653
 654 }  // namespace media