1 files changed, 24 insertions, 3 deletions

diff --git a/chromium/third_party/blink/renderer/platform/peerconnection/rtc_video_decoder_stream_adapter.h b/chromium/third_party/blink/renderer/platform/peerconnection/rtc_video_decoder_stream_adapter.h
index 6f1b5755913..ef362b4f905 100644
--- a/chromium/third_party/blink/renderer/platform/peerconnection/rtc_video_decoder_stream_adapter.h
+++ b/chromium/third_party/blink/renderer/platform/peerconnection/rtc_video_decoder_stream_adapter.h
@@ -9,7 +9,6 @@
 #include <vector>
 
 #include "base/callback_forward.h"
-#include "base/macros.h"
 #include "base/memory/scoped_refptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequence_checker.h"
@@ -62,6 +61,20 @@ namespace blink {
 class PLATFORM_EXPORT RTCVideoDecoderStreamAdapter
     : public webrtc::VideoDecoder {
  public:
+  // Minimum resolution that we'll consider "not low resolution" for the purpose
+  // of falling back to software.
+#if defined(OS_CHROMEOS)
+  // Effectively opt-out CrOS, since it may cause tests to fail (b/179724180).
+  static constexpr gfx::Size kMinResolution{2, 2};
+#else
+  static constexpr gfx::Size kMinResolution{320, 240};
+#endif
+
+  // Maximum number of decoder instances we'll allow before fallback to software
+  // if the resolution is too low.  We'll allow more than this for high
+  // resolution streams, but they'll fall back if they adapt below the limit.
+  static constexpr int32_t kMaxDecoderInstances = 8;
+
   // Creates and initializes an RTCVideoDecoderStreamAdapter. Returns nullptr if
   // |format| cannot be supported. The gpu_factories may be null, in which case
   // only SW decoders will be used.
@@ -73,6 +86,10 @@ class PLATFORM_EXPORT RTCVideoDecoderStreamAdapter
       const gfx::ColorSpace& render_color_space,
       const webrtc::SdpVideoFormat& format);
 
+  RTCVideoDecoderStreamAdapter(const RTCVideoDecoderStreamAdapter&) = delete;
+  RTCVideoDecoderStreamAdapter& operator=(const RTCVideoDecoderStreamAdapter&) =
+      delete;
+
   // Called on |media_task_runner_|.
   ~RTCVideoDecoderStreamAdapter() override;
 
@@ -161,6 +178,8 @@ class PLATFORM_EXPORT RTCVideoDecoderStreamAdapter
   // Decoding thread members.
   bool key_frame_required_ = true;
   webrtc::VideoCodecType video_codec_type_ = webrtc::kVideoCodecGeneric;
+  // Has anything been sent to Decode() yet?
+  bool have_started_decoding_ = false;
 
   // Shared members.
   mutable base::Lock lock_;
@@ -184,6 +203,10 @@ class PLATFORM_EXPORT RTCVideoDecoderStreamAdapter
   // Time since construction.  Cleared when we record that a frame has been
   // successfully decoded.
   absl::optional<base::TimeTicks> start_time_ GUARDED_BY(lock_);
+  // Resolution of most recently decoded frame, or the initial resolution if we
+  // haven't decoded anything yet.  Since this is updated asynchronously, it's
+  // only an approximation of "most recently".
+  gfx::Size current_resolution_ GUARDED_BY(lock_);
 
   // Do we have an outstanding `DecoderStream::Read()`?
   // Media thread only.
@@ -202,8 +225,6 @@ class PLATFORM_EXPORT RTCVideoDecoderStreamAdapter
 
   base::WeakPtr<RTCVideoDecoderStreamAdapter> weak_this_;
   base::WeakPtrFactory<RTCVideoDecoderStreamAdapter> weak_this_factory_{this};
-
-  DISALLOW_COPY_AND_ASSIGN(RTCVideoDecoderStreamAdapter);
 };
 
 }  // namespace blink