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 "media/base/video_frame.h"
  11 #include "media/base/yuv_convert.h"
  12
  13 namespace media {
  14
  15 gfx::Size GetNaturalSize(const gfx::Size& visible_size,
  16                          int aspect_ratio_numerator,
  17                          int aspect_ratio_denominator) {
  18   if (aspect_ratio_denominator == 0 ||
  19       aspect_ratio_numerator < 0 ||
  20       aspect_ratio_denominator < 0)
  21     return gfx::Size();
  22
  23   double aspect_ratio = aspect_ratio_numerator /
  24       static_cast<double>(aspect_ratio_denominator);
  25
  26   int width = floor(visible_size.width() * aspect_ratio + 0.5);
  27   int height = visible_size.height();
  28
  29   // An even width makes things easier for YV12 and appears to be the behavior
  30   // expected by WebKit layout tests.
  31   return gfx::Size(width & ~1, height);
  32 }
  33
  34 void CopyPlane(size_t plane, const uint8* source, int stride, int rows,
  35                VideoFrame* frame) {
  36   uint8* dest = frame->data(plane);
  37   int dest_stride = frame->stride(plane);
  38
  39   // Clamp in case source frame has smaller stride.
  40   int bytes_to_copy_per_row = std::min(frame->row_bytes(plane), stride);
  41
  42   // Clamp in case source frame has smaller height.
  43   int rows_to_copy = std::min(frame->rows(plane), rows);
  44
  45   // Copy!
  46   for (int row = 0; row < rows_to_copy; ++row) {
  47     memcpy(dest, source, bytes_to_copy_per_row);
  48     source += stride;
  49     dest += dest_stride;
  50   }
  51 }
  52
  53 void CopyYPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  54   CopyPlane(VideoFrame::kYPlane, source, stride, rows, frame);
  55 }
  56
  57 void CopyUPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  58   CopyPlane(VideoFrame::kUPlane, source, stride, rows, frame);
  59 }
  60
  61 void CopyVPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  62   CopyPlane(VideoFrame::kVPlane, source, stride, rows, frame);
  63 }
  64
  65 void CopyAPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  66   CopyPlane(VideoFrame::kAPlane, source, stride, rows, frame);
  67 }
  68
  69 void MakeOpaqueAPlane(int stride, int rows, VideoFrame* frame) {
  70   int rows_to_clear = std::min(frame->rows(VideoFrame::kAPlane), rows);
  71   memset(frame->data(VideoFrame::kAPlane), 255,
  72          frame->stride(VideoFrame::kAPlane) * rows_to_clear);
  73 }
  74
  75 void FillYUV(VideoFrame* frame, uint8 y, uint8 u, uint8 v) {
  76   // Fill the Y plane.
  77   uint8* y_plane = frame->data(VideoFrame::kYPlane);
  78   int y_rows = frame->rows(VideoFrame::kYPlane);
  79   int y_row_bytes = frame->row_bytes(VideoFrame::kYPlane);
  80   for (int i = 0; i < y_rows; ++i) {
  81     memset(y_plane, y, y_row_bytes);
  82     y_plane += frame->stride(VideoFrame::kYPlane);
  83   }
  84
  85   // Fill the U and V planes.
  86   uint8* u_plane = frame->data(VideoFrame::kUPlane);
  87   uint8* v_plane = frame->data(VideoFrame::kVPlane);
  88   int uv_rows = frame->rows(VideoFrame::kUPlane);
  89   int u_row_bytes = frame->row_bytes(VideoFrame::kUPlane);
  90   int v_row_bytes = frame->row_bytes(VideoFrame::kVPlane);
  91   for (int i = 0; i < uv_rows; ++i) {
  92     memset(u_plane, u, u_row_bytes);
  93     memset(v_plane, v, v_row_bytes);
  94     u_plane += frame->stride(VideoFrame::kUPlane);
  95     v_plane += frame->stride(VideoFrame::kVPlane);
  96   }
  97 }
  98
  99 static void LetterboxPlane(VideoFrame* frame,
 100                            int plane,
 101                            const gfx::Rect& view_area,
 102                            uint8 fill_byte) {
 103   uint8* ptr = frame->data(plane);
 104   const int rows = frame->rows(plane);
 105   const int row_bytes = frame->row_bytes(plane);
 106   const int stride = frame->stride(plane);
 107
 108   CHECK_GE(stride, row_bytes);
 109   CHECK_GE(view_area.x(), 0);
 110   CHECK_GE(view_area.y(), 0);
 111   CHECK_LE(view_area.right(), row_bytes);
 112   CHECK_LE(view_area.bottom(), rows);
 113
 114   int y = 0;
 115   for (; y < view_area.y(); y++) {
 116     memset(ptr, fill_byte, row_bytes);
 117     ptr += stride;
 118   }
 119   if (view_area.width() < row_bytes) {
 120     for (; y < view_area.bottom(); y++) {
 121       if (view_area.x() > 0) {
 122         memset(ptr, fill_byte, view_area.x());
 123       }
 124       if (view_area.right() < row_bytes) {
 125         memset(ptr + view_area.right(),
 126                fill_byte,
 127                row_bytes - view_area.right());
 128       }
 129       ptr += stride;
 130     }
 131   } else {
 132     y += view_area.height();
 133     ptr += stride * view_area.height();
 134   }
 135   for (; y < rows; y++) {
 136     memset(ptr, fill_byte, row_bytes);
 137     ptr += stride;
 138   }
 139 }
 140
 141 void LetterboxYUV(VideoFrame* frame, const gfx::Rect& view_area) {
 142   DCHECK(!(view_area.x() & 1));
 143   DCHECK(!(view_area.y() & 1));
 144   DCHECK(!(view_area.width() & 1));
 145   DCHECK(!(view_area.height() & 1));
 146   DCHECK(frame->format() == VideoFrame::YV12 ||
 147          frame->format() == VideoFrame::YV12J ||
 148          frame->format() == VideoFrame::I420);
 149   LetterboxPlane(frame, VideoFrame::kYPlane, view_area, 0x00);
 150   gfx::Rect half_view_area(view_area.x() / 2,
 151                            view_area.y() / 2,
 152                            view_area.width() / 2,
 153                            view_area.height() / 2);
 154   LetterboxPlane(frame, VideoFrame::kUPlane, half_view_area, 0x80);
 155   LetterboxPlane(frame, VideoFrame::kVPlane, half_view_area, 0x80);
 156 }
 157
 158 void RotatePlaneByPixels(
 159     const uint8* src,
 160     uint8* dest,
 161     int width,
 162     int height,
 163     int rotation,  // Clockwise.
 164     bool flip_vert,
 165     bool flip_horiz) {
 166   DCHECK((width > 0) && (height > 0) &&
 167          ((width & 1) == 0) && ((height & 1) == 0) &&
 168          (rotation >= 0) && (rotation < 360) && (rotation % 90 == 0));
 169
 170   // Consolidate cases. Only 0 and 90 are left.
 171   if (rotation == 180 || rotation == 270) {
 172     rotation -= 180;
 173     flip_vert = !flip_vert;
 174     flip_horiz = !flip_horiz;
 175   }
 176
 177   int num_rows = height;
 178   int num_cols = width;
 179   int src_stride = width;
 180   // During pixel copying, the corresponding incremental of dest pointer
 181   // when src pointer moves to next row.
 182   int dest_row_step = width;
 183   // During pixel copying, the corresponding incremental of dest pointer
 184   // when src pointer moves to next column.
 185   int dest_col_step = 1;
 186
 187   if (rotation == 0) {
 188     if (flip_horiz) {
 189       // Use pixel copying.
 190       dest_col_step = -1;
 191       if (flip_vert) {
 192         // Rotation 180.
 193         dest_row_step = -width;
 194         dest += height * width - 1;
 195       } else {
 196         dest += width - 1;
 197       }
 198     } else {
 199       if (flip_vert) {
 200         // Fast copy by rows.
 201         dest += width * (height - 1);
 202         for (int row = 0; row < height; ++row) {
 203           memcpy(dest, src, width);
 204           src += width;
 205           dest -= width;
 206         }
 207       } else {
 208         memcpy(dest, src, width * height);
 209       }
 210       return;
 211     }
 212   } else if (rotation == 90) {
 213     int offset;
 214     if (width > height) {
 215       offset = (width - height) / 2;
 216       src += offset;
 217       num_rows = num_cols = height;
 218     } else {
 219       offset = (height - width) / 2;
 220       src += width * offset;
 221       num_rows = num_cols = width;
 222     }
 223
 224     dest_col_step = (flip_vert ? -width : width);
 225     dest_row_step = (flip_horiz ? 1 : -1);
 226     if (flip_horiz) {
 227       if (flip_vert) {
 228         dest += (width > height ? width * (height - 1) + offset :
 229                                   width * (height - offset - 1));
 230       } else {
 231         dest += (width > height ? offset : width * offset);
 232       }
 233     } else {
 234       if (flip_vert) {
 235         dest += (width > height ?  width * height - offset - 1 :
 236                                    width * (height - offset) - 1);
 237       } else {
 238         dest += (width > height ? width - offset - 1 :
 239                                   width * (offset + 1) - 1);
 240       }
 241     }
 242   } else {
 243     NOTREACHED();
 244   }
 245
 246   // Copy pixels.
 247   for (int row = 0; row < num_rows; ++row) {
 248     const uint8* src_ptr = src;
 249     uint8* dest_ptr = dest;
 250     for (int col = 0; col < num_cols; ++col) {
 251       *dest_ptr = *src_ptr++;
 252       dest_ptr += dest_col_step;
 253     }
 254     src += src_stride;
 255     dest += dest_row_step;
 256   }
 257 }
 258
 259 gfx::Rect ComputeLetterboxRegion(const gfx::Rect& bounds,
 260                                  const gfx::Size& content) {
 261   // If |content| has an undefined aspect ratio, let's not try to divide by
 262   // zero.
 263   if (content.IsEmpty())
 264     return gfx::Rect();
 265
 266   int64 x = static_cast<int64>(content.width()) * bounds.height();
 267   int64 y = static_cast<int64>(content.height()) * bounds.width();
 268
 269   gfx::Size letterbox(bounds.width(), bounds.height());
 270   if (y < x)
 271     letterbox.set_height(static_cast<int>(y / content.width()));
 272   else
 273     letterbox.set_width(static_cast<int>(x / content.height()));
 274   gfx::Rect result = bounds;
 275   result.ClampToCenteredSize(letterbox);
 276   return result;
 277 }
 278
 279 void CopyRGBToVideoFrame(const uint8* source,
 280                          int stride,
 281                          const gfx::Rect& region_in_frame,
 282                          VideoFrame* frame) {
 283   const int kY = VideoFrame::kYPlane;
 284   const int kU = VideoFrame::kUPlane;
 285   const int kV = VideoFrame::kVPlane;
 286   CHECK_EQ(frame->stride(kU), frame->stride(kV));
 287   const int uv_stride = frame->stride(kU);
 288
 289   if (region_in_frame != gfx::Rect(frame->coded_size())) {
 290     LetterboxYUV(frame, region_in_frame);
 291   }
 292
 293   const int y_offset = region_in_frame.x()
 294                      + (region_in_frame.y() * frame->stride(kY));
 295   const int uv_offset = region_in_frame.x() / 2
 296                       + (region_in_frame.y() / 2 * uv_stride);
 297
 298   ConvertRGB32ToYUV(source,
 299                     frame->data(kY) + y_offset,
 300                     frame->data(kU) + uv_offset,
 301                     frame->data(kV) + uv_offset,
 302                     region_in_frame.width(),
 303                     region_in_frame.height(),
 304                     stride,
 305                     frame->stride(kY),
 306                     uv_stride);
 307 }
 308
 309 }  // namespace media