H264SPS: Centralize computation of coded size and visible rect.

media/formats/mp2t/es_parser_h264.cc

Index: media/formats/mp2t/es_parser_h264.cc
diff --git a/media/formats/mp2t/es_parser_h264.cc b/media/formats/mp2t/es_parser_h264.cc
index c074d544356fb581f3369d2c528f19ddbc14ccd8..89d7c4c285d9d778b738b7381c0417713a291433 100644
--- a/media/formats/mp2t/es_parser_h264.cc
+++ b/media/formats/mp2t/es_parser_h264.cc
@@ -8,6 +8,7 @@
 
 #include "base/logging.h"
 #include "base/numerics/safe_conversions.h"
+#include "base/optional.h"
 #include "media/base/encryption_scheme.h"
 #include "media/base/media_util.h"
 #include "media/base/stream_parser_buffer.h"
@@ -261,48 +262,34 @@ bool EsParserH264::UpdateVideoDecoderConfig(const H264SPS* sps,
   int sar_width = (sps->sar_width == 0) ? 1 : sps->sar_width;
   int sar_height = (sps->sar_height == 0) ? 1 : sps->sar_height;
 
-  // TODO(damienv): a MAP unit can be either 16 or 32 pixels.
-  // although it's 16 pixels for progressive non MBAFF frames.
-  int width_mb = sps->pic_width_in_mbs_minus1 + 1;
-  int height_mb = sps->pic_height_in_map_units_minus1 + 1;
-  if (width_mb > std::numeric_limits<int>::max() / 16 ||
-      height_mb > std::numeric_limits<int>::max() / 16) {
-    DVLOG(1) << "Picture size is too big: width_mb=" << width_mb
-             << " height_mb=" << height_mb;
+  base::Optional<gfx::Size> coded_size = sps->GetCodedSize();
+  if (!coded_size)
     return false;
-  }
 
-  gfx::Size coded_size(16 * width_mb, 16 * height_mb);
-  gfx::Rect visible_rect(
-      sps->frame_crop_left_offset,
-      sps->frame_crop_top_offset,
-      (coded_size.width() - sps->frame_crop_right_offset) -
-      sps->frame_crop_left_offset,
-      (coded_size.height() - sps->frame_crop_bottom_offset) -
-      sps->frame_crop_top_offset);
-  if (visible_rect.width() <= 0 || visible_rect.height() <= 0)
+  base::Optional<gfx::Rect> visible_rect = sps->GetVisibleRect();
+  if (!visible_rect)
     return false;
-  if (visible_rect.width() > std::numeric_limits<int>::max() / sar_width) {
+
+  if (visible_rect->width() > std::numeric_limits<int>::max() / sar_width) {
     DVLOG(1) << "Integer overflow detected: visible_rect.width()="
-             << visible_rect.width() << " sar_width=" << sar_width;
+             << visible_rect->width() << " sar_width=" << sar_width;
     return false;
   }
-  gfx::Size natural_size(
-      (visible_rect.width() * sar_width) / sar_height,
-      visible_rect.height());
+  gfx::Size natural_size((visible_rect->width() * sar_width) / sar_height,
+                         visible_rect->height());
   if (natural_size.width() == 0)
     return false;
 
   VideoDecoderConfig video_decoder_config(
       kCodecH264, H264Parser::ProfileIDCToVideoCodecProfile(sps->profile_idc),
-      PIXEL_FORMAT_YV12, COLOR_SPACE_HD_REC709, coded_size, visible_rect,
-      natural_size, EmptyExtraData(), scheme);
+      PIXEL_FORMAT_YV12, COLOR_SPACE_HD_REC709, coded_size.value(),
+      visible_rect.value(), natural_size, EmptyExtraData(), scheme);
 
   if (!video_decoder_config.Matches(last_video_decoder_config_)) {
     DVLOG(1) << "Profile IDC: " << sps->profile_idc;
     DVLOG(1) << "Level IDC: " << sps->level_idc;
-    DVLOG(1) << "Pic width: " << coded_size.width();
-    DVLOG(1) << "Pic height: " << coded_size.height();
+    DVLOG(1) << "Pic width: " << coded_size->width();
+    DVLOG(1) << "Pic height: " << coded_size->height();
     DVLOG(1) << "log2_max_frame_num_minus4: "
              << sps->log2_max_frame_num_minus4;
     DVLOG(1) << "SAR: width=" << sps->sar_width