media/base/video_util.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 #include "media/base/video_util.h"
   6
   7 #include <cmath>
   8
   9 #include "base/logging.h"
  10 #include "base/numerics/safe_conversions.h"
  11 #include "base/numerics/safe_math.h"
  12 #include "media/base/video_frame.h"
  13 #include "media/base/yuv_convert.h"
  14
  15 namespace media {
  16
  17 gfx::Size GetNaturalSize(const gfx::Size& visible_size,
  18                          int aspect_ratio_numerator,
  19                          int aspect_ratio_denominator) {
  20   if (aspect_ratio_denominator == 0 ||
  21       aspect_ratio_numerator < 0 ||
  22       aspect_ratio_denominator < 0)
  23     return gfx::Size();
  24
  25   double aspect_ratio = aspect_ratio_numerator /
  26       static_cast<double>(aspect_ratio_denominator);
  27
  28   return gfx::Size(round(visible_size.width() * aspect_ratio),
  29                    visible_size.height());
  30 }
  31
  32 void CopyPlane(size_t plane, const uint8* source, int stride, int rows,
  33                VideoFrame* frame) {
  34   uint8* dest = frame->data(plane);
  35   int dest_stride = frame->stride(plane);
  36
  37   // Clamp in case source frame has smaller stride.
  38   int bytes_to_copy_per_row = std::min(frame->row_bytes(plane), stride);
  39
  40   // Clamp in case source frame has smaller height.
  41   int rows_to_copy = std::min(frame->rows(plane), rows);
  42
  43   // Copy!
  44   for (int row = 0; row < rows_to_copy; ++row) {
  45     memcpy(dest, source, bytes_to_copy_per_row);
  46     source += stride;
  47     dest += dest_stride;
  48   }
  49 }
  50
  51 void CopyYPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  52   CopyPlane(VideoFrame::kYPlane, source, stride, rows, frame);
  53 }
  54
  55 void CopyUPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  56   CopyPlane(VideoFrame::kUPlane, source, stride, rows, frame);
  57 }
  58
  59 void CopyVPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  60   CopyPlane(VideoFrame::kVPlane, source, stride, rows, frame);
  61 }
  62
  63 void CopyAPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  64   CopyPlane(VideoFrame::kAPlane, source, stride, rows, frame);
  65 }
  66
  67 void MakeOpaqueAPlane(int stride, int rows, VideoFrame* frame) {
  68   int rows_to_clear = std::min(frame->rows(VideoFrame::kAPlane), rows);
  69   memset(frame->data(VideoFrame::kAPlane), 255,
  70          frame->stride(VideoFrame::kAPlane) * rows_to_clear);
  71 }
  72
  73 void FillYUV(VideoFrame* frame, uint8 y, uint8 u, uint8 v) {
  74   // Fill the Y plane.
  75   uint8* y_plane = frame->data(VideoFrame::kYPlane);
  76   int y_rows = frame->rows(VideoFrame::kYPlane);
  77   int y_row_bytes = frame->row_bytes(VideoFrame::kYPlane);
  78   for (int i = 0; i < y_rows; ++i) {
  79     memset(y_plane, y, y_row_bytes);
  80     y_plane += frame->stride(VideoFrame::kYPlane);
  81   }
  82
  83   // Fill the U and V planes.
  84   uint8* u_plane = frame->data(VideoFrame::kUPlane);
  85   uint8* v_plane = frame->data(VideoFrame::kVPlane);
  86   int uv_rows = frame->rows(VideoFrame::kUPlane);
  87   int u_row_bytes = frame->row_bytes(VideoFrame::kUPlane);
  88   int v_row_bytes = frame->row_bytes(VideoFrame::kVPlane);
  89   for (int i = 0; i < uv_rows; ++i) {
  90     memset(u_plane, u, u_row_bytes);
  91     memset(v_plane, v, v_row_bytes);
  92     u_plane += frame->stride(VideoFrame::kUPlane);
  93     v_plane += frame->stride(VideoFrame::kVPlane);
  94   }
  95 }
  96
  97 void FillYUVA(VideoFrame* frame, uint8 y, uint8 u, uint8 v, uint8 a) {
  98   // Fill Y, U and V planes.
  99   FillYUV(frame, y, u, v);
 100
 101   // Fill the A plane.
 102   uint8* a_plane = frame->data(VideoFrame::kAPlane);
 103   int a_rows = frame->rows(VideoFrame::kAPlane);
 104   int a_row_bytes = frame->row_bytes(VideoFrame::kAPlane);
 105   for (int i = 0; i < a_rows; ++i) {
 106     memset(a_plane, a, a_row_bytes);
 107     a_plane += frame->stride(VideoFrame::kAPlane);
 108   }
 109 }
 110
 111 static void LetterboxPlane(VideoFrame* frame,
 112                            int plane,
 113                            const gfx::Rect& view_area,
 114                            uint8 fill_byte) {
 115   uint8* ptr = frame->data(plane);
 116   const int rows = frame->rows(plane);
 117   const int row_bytes = frame->row_bytes(plane);
 118   const int stride = frame->stride(plane);
 119
 120   CHECK_GE(stride, row_bytes);
 121   CHECK_GE(view_area.x(), 0);
 122   CHECK_GE(view_area.y(), 0);
 123   CHECK_LE(view_area.right(), row_bytes);
 124   CHECK_LE(view_area.bottom(), rows);
 125
 126   int y = 0;
 127   for (; y < view_area.y(); y++) {
 128     memset(ptr, fill_byte, row_bytes);
 129     ptr += stride;
 130   }
 131   if (view_area.width() < row_bytes) {
 132     for (; y < view_area.bottom(); y++) {
 133       if (view_area.x() > 0) {
 134         memset(ptr, fill_byte, view_area.x());
 135       }
 136       if (view_area.right() < row_bytes) {
 137         memset(ptr + view_area.right(),
 138                fill_byte,
 139                row_bytes - view_area.right());
 140       }
 141       ptr += stride;
 142     }
 143   } else {
 144     y += view_area.height();
 145     ptr += stride * view_area.height();
 146   }
 147   for (; y < rows; y++) {
 148     memset(ptr, fill_byte, row_bytes);
 149     ptr += stride;
 150   }
 151 }
 152
 153 void LetterboxYUV(VideoFrame* frame, const gfx::Rect& view_area) {
 154   DCHECK(!(view_area.x() & 1));
 155   DCHECK(!(view_area.y() & 1));
 156   DCHECK(!(view_area.width() & 1));
 157   DCHECK(!(view_area.height() & 1));
 158   DCHECK(frame->format() == PIXEL_FORMAT_YV12 ||
 159          frame->format() == PIXEL_FORMAT_I420);
 160   LetterboxPlane(frame, VideoFrame::kYPlane, view_area, 0x00);
 161   gfx::Rect half_view_area(view_area.x() / 2,
 162                            view_area.y() / 2,
 163                            view_area.width() / 2,
 164                            view_area.height() / 2);
 165   LetterboxPlane(frame, VideoFrame::kUPlane, half_view_area, 0x80);
 166   LetterboxPlane(frame, VideoFrame::kVPlane, half_view_area, 0x80);
 167 }
 168
 169 void RotatePlaneByPixels(
 170     const uint8* src,
 171     uint8* dest,
 172     int width,
 173     int height,
 174     int rotation,  // Clockwise.
 175     bool flip_vert,
 176     bool flip_horiz) {
 177   DCHECK((width > 0) && (height > 0) &&
 178          ((width & 1) == 0) && ((height & 1) == 0) &&
 179          (rotation >= 0) && (rotation < 360) && (rotation % 90 == 0));
 180
 181   // Consolidate cases. Only 0 and 90 are left.
 182   if (rotation == 180 || rotation == 270) {
 183     rotation -= 180;
 184     flip_vert = !flip_vert;
 185     flip_horiz = !flip_horiz;
 186   }
 187
 188   int num_rows = height;
 189   int num_cols = width;
 190   int src_stride = width;
 191   // During pixel copying, the corresponding incremental of dest pointer
 192   // when src pointer moves to next row.
 193   int dest_row_step = width;
 194   // During pixel copying, the corresponding incremental of dest pointer
 195   // when src pointer moves to next column.
 196   int dest_col_step = 1;
 197
 198   if (rotation == 0) {
 199     if (flip_horiz) {
 200       // Use pixel copying.
 201       dest_col_step = -1;
 202       if (flip_vert) {
 203         // Rotation 180.
 204         dest_row_step = -width;
 205         dest += height * width - 1;
 206       } else {
 207         dest += width - 1;
 208       }
 209     } else {
 210       if (flip_vert) {
 211         // Fast copy by rows.
 212         dest += width * (height - 1);
 213         for (int row = 0; row < height; ++row) {
 214           memcpy(dest, src, width);
 215           src += width;
 216           dest -= width;
 217         }
 218       } else {
 219         memcpy(dest, src, width * height);
 220       }
 221       return;
 222     }
 223   } else if (rotation == 90) {
 224     int offset;
 225     if (width > height) {
 226       offset = (width - height) / 2;
 227       src += offset;
 228       num_rows = num_cols = height;
 229     } else {
 230       offset = (height - width) / 2;
 231       src += width * offset;
 232       num_rows = num_cols = width;
 233     }
 234
 235     dest_col_step = (flip_vert ? -width : width);
 236     dest_row_step = (flip_horiz ? 1 : -1);
 237     if (flip_horiz) {
 238       if (flip_vert) {
 239         dest += (width > height ? width * (height - 1) + offset :
 240                                   width * (height - offset - 1));
 241       } else {
 242         dest += (width > height ? offset : width * offset);
 243       }
 244     } else {
 245       if (flip_vert) {
 246         dest += (width > height ?  width * height - offset - 1 :
 247                                    width * (height - offset) - 1);
 248       } else {
 249         dest += (width > height ? width - offset - 1 :
 250                                   width * (offset + 1) - 1);
 251       }
 252     }
 253   } else {
 254     NOTREACHED();
 255   }
 256
 257   // Copy pixels.
 258   for (int row = 0; row < num_rows; ++row) {
 259     const uint8* src_ptr = src;
 260     uint8* dest_ptr = dest;
 261     for (int col = 0; col < num_cols; ++col) {
 262       *dest_ptr = *src_ptr++;
 263       dest_ptr += dest_col_step;
 264     }
 265     src += src_stride;
 266     dest += dest_row_step;
 267   }
 268 }
 269
 270 // Helper function to return |a| divided by |b|, rounded to the nearest integer.
 271 static int RoundedDivision(int64 a, int b) {
 272   DCHECK_GE(a, 0);
 273   DCHECK_GT(b, 0);
 274   base::CheckedNumeric<uint64> result(a);
 275   result += b / 2;
 276   result /= b;
 277   return base::checked_cast<int>(result.ValueOrDie());
 278 }
 279
 280 // Common logic for the letterboxing and scale-within/scale-encompassing
 281 // functions.  Scales |size| to either fit within or encompass |target|,
 282 // depending on whether |fit_within_target| is true.
 283 static gfx::Size ScaleSizeToTarget(const gfx::Size& size,
 284                                    const gfx::Size& target,
 285                                    bool fit_within_target) {
 286   if (size.IsEmpty())
 287     return gfx::Size();  // Corner case: Aspect ratio is undefined.
 288
 289   const int64 x = static_cast<int64>(size.width()) * target.height();
 290   const int64 y = static_cast<int64>(size.height()) * target.width();
 291   const bool use_target_width = fit_within_target ? (y < x) : (x < y);
 292   return use_target_width ?
 293       gfx::Size(target.width(), RoundedDivision(y, size.width())) :
 294       gfx::Size(RoundedDivision(x, size.height()), target.height());
 295 }
 296
 297 gfx::Rect ComputeLetterboxRegion(const gfx::Rect& bounds,
 298                                  const gfx::Size& content) {
 299   // If |content| has an undefined aspect ratio, let's not try to divide by
 300   // zero.
 301   if (content.IsEmpty())
 302     return gfx::Rect();
 303
 304   gfx::Rect result = bounds;
 305   result.ClampToCenteredSize(ScaleSizeToTarget(content, bounds.size(), true));
 306   return result;
 307 }
 308
 309 gfx::Size ScaleSizeToFitWithinTarget(const gfx::Size& size,
 310                                      const gfx::Size& target) {
 311   return ScaleSizeToTarget(size, target, true);
 312 }
 313
 314 gfx::Size ScaleSizeToEncompassTarget(const gfx::Size& size,
 315                                      const gfx::Size& target) {
 316   return ScaleSizeToTarget(size, target, false);
 317 }
 318
 319 gfx::Size PadToMatchAspectRatio(const gfx::Size& size,
 320                                 const gfx::Size& target) {
 321   if (target.IsEmpty())
 322     return gfx::Size();  // Aspect ratio is undefined.
 323
 324   const int64 x = static_cast<int64>(size.width()) * target.height();
 325   const int64 y = static_cast<int64>(size.height()) * target.width();
 326   if (x < y)
 327     return gfx::Size(RoundedDivision(y, target.height()), size.height());
 328   return gfx::Size(size.width(), RoundedDivision(x, target.width()));
 329 }
 330
 331 void CopyRGBToVideoFrame(const uint8* source,
 332                          int stride,
 333                          const gfx::Rect& region_in_frame,
 334                          VideoFrame* frame) {
 335   const int kY = VideoFrame::kYPlane;
 336   const int kU = VideoFrame::kUPlane;
 337   const int kV = VideoFrame::kVPlane;
 338   CHECK_EQ(frame->stride(kU), frame->stride(kV));
 339   const int uv_stride = frame->stride(kU);
 340
 341   if (region_in_frame != gfx::Rect(frame->coded_size())) {
 342     LetterboxYUV(frame, region_in_frame);
 343   }
 344
 345   const int y_offset = region_in_frame.x()
 346                      + (region_in_frame.y() * frame->stride(kY));
 347   const int uv_offset = region_in_frame.x() / 2
 348                       + (region_in_frame.y() / 2 * uv_stride);
 349
 350   ConvertRGB32ToYUV(source,
 351                     frame->data(kY) + y_offset,
 352                     frame->data(kU) + uv_offset,
 353                     frame->data(kV) + uv_offset,
 354                     region_in_frame.width(),
 355                     region_in_frame.height(),
 356                     stride,
 357                     frame->stride(kY),
 358                     uv_stride);
 359 }
 360
 361 }  // namespace media