Implement external decoder support in WebRtcVideoEngine2.

R=stefan@webrtc.org
BUG=1788

Review URL: https://webrtc-codereview.appspot.com/30839004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/talk@7594 4adac7df-926f-26a2-2b94-8c16560cd09d

3 files changed, 177 insertions, 83 deletions

diff --git a/media/webrtc/webrtcvideoengine2.cc b/media/webrtc/webrtcvideoengine2.cc
index d902718..a877921 100644
--- a/media/webrtc/webrtcvideoengine2.cc
+++ b/media/webrtc/webrtcvideoengine2.cc
@@ -57,10 +57,18 @@ static bool CodecNameMatches(const std::string& name1,
   return _stricmp(name1.c_str(), name2.c_str()) == 0;
 }
 
+const char* kInternallySupportedCodecs[] = {
+    kVp8CodecName,
+};
+
 // True if codec is supported by a software implementation that's always
 // available.
 static bool CodecIsInternallySupported(const std::string& codec_name) {
-  return CodecNameMatches(codec_name, kVp8CodecName);
+  for (size_t i = 0; i < ARRAY_SIZE(kInternallySupportedCodecs); ++i) {
+    if (CodecNameMatches(codec_name, kInternallySupportedCodecs[i]))
+      return true;
+  }
+  return false;
 }
 
 static std::string CodecVectorToString(const std::vector<VideoCodec>& codecs) {
@@ -807,6 +815,37 @@ WebRtcVideoChannel2::~WebRtcVideoChannel2() {
 
 bool WebRtcVideoChannel2::Init() { return true; }
 
+bool WebRtcVideoChannel2::CodecIsExternallySupported(
+    const std::string& name) const {
+  if (external_encoder_factory_ == NULL) {
+    return false;
+  }
+
+  const std::vector<WebRtcVideoEncoderFactory::VideoCodec> external_codecs =
+      external_encoder_factory_->codecs();
+  for (size_t c = 0; c < external_codecs.size(); ++c) {
+    if (CodecNameMatches(name, external_codecs[c].name)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+std::vector<WebRtcVideoChannel2::VideoCodecSettings>
+WebRtcVideoChannel2::FilterSupportedCodecs(
+    const std::vector<WebRtcVideoChannel2::VideoCodecSettings>& mapped_codecs)
+    const {
+  std::vector<VideoCodecSettings> supported_codecs;
+  for (size_t i = 0; i < mapped_codecs.size(); ++i) {
+    const VideoCodecSettings& codec = mapped_codecs[i];
+    if (CodecIsInternallySupported(codec.codec.name) ||
+        CodecIsExternallySupported(codec.codec.name)) {
+      supported_codecs.push_back(codec);
+    }
+  }
+  return supported_codecs;
+}
+
 bool WebRtcVideoChannel2::SetRecvCodecs(const std::vector<VideoCodec>& codecs) {
   LOG(LS_INFO) << "SetRecvCodecs: " << CodecVectorToString(codecs);
   if (!ValidateCodecFormats(codecs)) {
@@ -815,21 +854,19 @@ bool WebRtcVideoChannel2::SetRecvCodecs(const std::vector<VideoCodec>& codecs) {
 
   const std::vector<VideoCodecSettings> mapped_codecs = MapCodecs(codecs);
   if (mapped_codecs.empty()) {
-    LOG(LS_ERROR) << "SetRecvCodecs called without video codec payloads.";
+    LOG(LS_ERROR) << "SetRecvCodecs called without any video codecs.";
     return false;
   }
 
-  // TODO(pbos): Add a decoder factory which controls supported codecs.
-  // Blocked on webrtc:2854.
-  for (size_t i = 0; i < mapped_codecs.size(); ++i) {
-    if (!CodecNameMatches(mapped_codecs[i].codec.name, kVp8CodecName)) {
-      LOG(LS_ERROR) << "SetRecvCodecs called with unsupported codec: '"
-                    << mapped_codecs[i].codec.name << "'";
-      return false;
-    }
+  const std::vector<VideoCodecSettings> supported_codecs =
+      FilterSupportedCodecs(mapped_codecs);
+
+  if (mapped_codecs.size() != supported_codecs.size()) {
+    LOG(LS_ERROR) << "SetRecvCodecs called with unsupported video codecs.";
+    return false;
   }
 
-  recv_codecs_ = mapped_codecs;
+  recv_codecs_ = supported_codecs;
 
   rtc::CritScope stream_lock(&stream_crit_);
   for (std::map<uint32, WebRtcVideoReceiveStream*>::iterator it =
@@ -1899,34 +1936,67 @@ WebRtcVideoChannel2::WebRtcVideoReceiveStream::WebRtcVideoReceiveStream(
 
 WebRtcVideoChannel2::WebRtcVideoReceiveStream::~WebRtcVideoReceiveStream() {
   call_->DestroyVideoReceiveStream(stream_);
-  ClearDecoders();
+  ClearDecoders(&allocated_decoders_);
 }
 
-void WebRtcVideoChannel2::WebRtcVideoReceiveStream::SetRecvCodecs(
-    const std::vector<VideoCodecSettings>& recv_codecs) {
-  // TODO(pbos): Reconfigure RTX based on incoming recv_codecs.
-  // TODO(pbos): Base receive codecs off recv_codecs_ and set up using a
-  // DecoderFactory similar to send side. Pending webrtc:2854.
-  // Also set up default codecs if there's nothing in recv_codecs_.
-  ClearDecoders();
+WebRtcVideoChannel2::WebRtcVideoReceiveStream::AllocatedDecoder
+WebRtcVideoChannel2::WebRtcVideoReceiveStream::CreateOrReuseVideoDecoder(
+    std::vector<AllocatedDecoder>* old_decoders,
+    const VideoCodec& codec) {
+  webrtc::VideoCodecType type = CodecTypeFromName(codec.name);
 
-  AllocatedDecoder allocated_decoder(
-      webrtc::VideoDecoder::Create(webrtc::VideoDecoder::kVp8), false);
-  allocated_decoders_.push_back(allocated_decoder);
+  for (size_t i = 0; i < old_decoders->size(); ++i) {
+    if ((*old_decoders)[i].type == type) {
+      AllocatedDecoder decoder = (*old_decoders)[i];
+      (*old_decoders)[i] = old_decoders->back();
+      old_decoders->pop_back();
+      return decoder;
+    }
+  }
 
-  webrtc::VideoReceiveStream::Decoder decoder;
-  decoder.decoder = allocated_decoder.decoder;
-  decoder.payload_type = kDefaultVideoCodecPref.payload_type;
-  decoder.payload_name = "VP8";
+  if (external_decoder_factory_ != NULL) {
+    webrtc::VideoDecoder* decoder =
+        external_decoder_factory_->CreateVideoDecoder(type);
+    if (decoder != NULL) {
+      return AllocatedDecoder(decoder, type, true);
+    }
+  }
 
-  config_.decoders.push_back(decoder);
+  if (type == webrtc::kVideoCodecVP8) {
+    return AllocatedDecoder(
+        webrtc::VideoDecoder::Create(webrtc::VideoDecoder::kVp8), type, false);
+  }
 
-  config_.rtp.fec = recv_codecs.front().fec;
+  // This shouldn't happen, we should not be trying to create something we don't
+  // support.
+  assert(false);
+  return AllocatedDecoder(NULL, webrtc::kVideoCodecUnknown, false);
+}
+
+void WebRtcVideoChannel2::WebRtcVideoReceiveStream::SetRecvCodecs(
+    const std::vector<VideoCodecSettings>& recv_codecs) {
+  std::vector<AllocatedDecoder> old_decoders = allocated_decoders_;
+  allocated_decoders_.clear();
+  config_.decoders.clear();
+  for (size_t i = 0; i < recv_codecs.size(); ++i) {
+    AllocatedDecoder allocated_decoder =
+        CreateOrReuseVideoDecoder(&old_decoders, recv_codecs[i].codec);
+    allocated_decoders_.push_back(allocated_decoder);
 
+    webrtc::VideoReceiveStream::Decoder decoder;
+    decoder.decoder = allocated_decoder.decoder;
+    decoder.payload_type = recv_codecs[i].codec.id;
+    decoder.payload_name = recv_codecs[i].codec.name;
+    config_.decoders.push_back(decoder);
+  }
+
+  // TODO(pbos): Reconfigure RTX based on incoming recv_codecs.
+  config_.rtp.fec = recv_codecs.front().fec;
   config_.rtp.nack.rtp_history_ms =
       IsNackEnabled(recv_codecs.begin()->codec) ? kNackHistoryMs : 0;
   config_.rtp.remb = IsRembEnabled(recv_codecs.begin()->codec);
 
+  ClearDecoders(&old_decoders);
   RecreateWebRtcStream();
 }
 
@@ -1944,16 +2014,17 @@ void WebRtcVideoChannel2::WebRtcVideoReceiveStream::RecreateWebRtcStream() {
   stream_->Start();
 }
 
-void WebRtcVideoChannel2::WebRtcVideoReceiveStream::ClearDecoders() {
-  for (size_t i = 0; i < allocated_decoders_.size(); ++i) {
-    if (allocated_decoders_[i].external) {
+void WebRtcVideoChannel2::WebRtcVideoReceiveStream::ClearDecoders(
+    std::vector<AllocatedDecoder>* allocated_decoders) {
+  for (size_t i = 0; i < allocated_decoders->size(); ++i) {
+    if ((*allocated_decoders)[i].external) {
       external_decoder_factory_->DestroyVideoDecoder(
-          allocated_decoders_[i].decoder);
+          (*allocated_decoders)[i].decoder);
     } else {
-      delete allocated_decoders_[i].decoder;
+      delete (*allocated_decoders)[i].decoder;
     }
   }
-  allocated_decoders_.clear();
+  allocated_decoders->clear();
 }
 
 void WebRtcVideoChannel2::WebRtcVideoReceiveStream::RenderFrame(
@@ -2115,31 +2186,6 @@ WebRtcVideoChannel2::MapCodecs(const std::vector<VideoCodec>& codecs) {
   return video_codecs;
 }
 
-std::vector<WebRtcVideoChannel2::VideoCodecSettings>
-WebRtcVideoChannel2::FilterSupportedCodecs(
-    const std::vector<WebRtcVideoChannel2::VideoCodecSettings>& mapped_codecs) {
-  std::vector<VideoCodecSettings> supported_codecs;
-  for (size_t i = 0; i < mapped_codecs.size(); ++i) {
-    const VideoCodecSettings& codec = mapped_codecs[i];
-    if (CodecIsInternallySupported(codec.codec.name)) {
-      supported_codecs.push_back(codec);
-    }
-
-    if (external_encoder_factory_ == NULL) {
-      continue;
-    }
-    const std::vector<WebRtcVideoEncoderFactory::VideoCodec> external_codecs =
-        external_encoder_factory_->codecs();
-    for (size_t c = 0; c < external_codecs.size(); ++c) {
-      if (CodecNameMatches(codec.codec.name, external_codecs[c].name)) {
-        supported_codecs.push_back(codec);
-        break;
-      }
-    }
-  }
-  return supported_codecs;
-}
-
 }  // namespace cricket
 
 #endif  // HAVE_WEBRTC_VIDEO
diff --git a/media/webrtc/webrtcvideoengine2.h b/media/webrtc/webrtcvideoengine2.h
index b9a8682..0b812ef 100644
--- a/media/webrtc/webrtcvideoengine2.h
+++ b/media/webrtc/webrtcvideoengine2.h
@@ -276,6 +276,7 @@ class WebRtcVideoChannel2 : public rtc::MessageHandler,
  private:
   void ConfigureReceiverRtp(webrtc::VideoReceiveStream::Config* config,
                             const StreamParams& sp) const;
+  bool CodecIsExternallySupported(const std::string& name) const;
 
   struct VideoCodecSettings {
     VideoCodecSettings();
@@ -408,16 +409,22 @@ class WebRtcVideoChannel2 : public rtc::MessageHandler,
 
    private:
     struct AllocatedDecoder {
-      AllocatedDecoder(webrtc::VideoDecoder* decoder, bool external)
-          : decoder(decoder), external(external) {}
+      AllocatedDecoder(webrtc::VideoDecoder* decoder,
+                       webrtc::VideoCodecType type,
+                       bool external)
+          : decoder(decoder), type(type), external(external) {}
       webrtc::VideoDecoder* decoder;
+      webrtc::VideoCodecType type;
       bool external;
     };
 
     void SetSize(int width, int height);
     void RecreateWebRtcStream();
 
-    void ClearDecoders();
+    AllocatedDecoder CreateOrReuseVideoDecoder(
+        std::vector<AllocatedDecoder>* old_decoder,
+        const VideoCodec& codec);
+    void ClearDecoders(std::vector<AllocatedDecoder>* allocated_decoders);
 
     webrtc::Call* const call_;
 
@@ -445,7 +452,7 @@ class WebRtcVideoChannel2 : public rtc::MessageHandler,
   static std::vector<VideoCodecSettings> MapCodecs(
       const std::vector<VideoCodec>& codecs);
   std::vector<VideoCodecSettings> FilterSupportedCodecs(
-      const std::vector<VideoCodecSettings>& mapped_codecs);
+      const std::vector<VideoCodecSettings>& mapped_codecs) const;
 
   void FillSenderStats(VideoMediaInfo* info);
   void FillReceiverStats(VideoMediaInfo* info);
diff --git a/media/webrtc/webrtcvideoengine2_unittest.cc b/media/webrtc/webrtcvideoengine2_unittest.cc
index 7c8da13..e45ad6d 100644
--- a/media/webrtc/webrtcvideoengine2_unittest.cc
+++ b/media/webrtc/webrtcvideoengine2_unittest.cc
@@ -349,6 +349,10 @@ class WebRtcVideoEngine2Test : public ::testing::Test {
       cricket::WebRtcVideoEncoderFactory* encoder_factory,
       const std::vector<VideoCodec>& codecs);
 
+  VideoMediaChannel* SetUpForExternalDecoderFactory(
+      cricket::WebRtcVideoDecoderFactory* decoder_factory,
+      const std::vector<VideoCodec>& codecs);
+
   void TestStartBitrate(bool override_start_bitrate, int start_bitrate_bps);
 
   WebRtcVideoEngine2 engine_;
@@ -579,6 +583,19 @@ VideoMediaChannel* WebRtcVideoEngine2Test::SetUpForExternalEncoderFactory(
   return channel;
 }
 
+VideoMediaChannel* WebRtcVideoEngine2Test::SetUpForExternalDecoderFactory(
+    cricket::WebRtcVideoDecoderFactory* decoder_factory,
+    const std::vector<VideoCodec>& codecs) {
+  engine_.SetExternalDecoderFactory(decoder_factory);
+  engine_.Init(rtc::Thread::Current());
+
+  VideoMediaChannel* channel =
+      engine_.CreateChannel(cricket::VideoOptions(), NULL);
+  EXPECT_TRUE(channel->SetRecvCodecs(codecs));
+
+  return channel;
+}
+
 TEST_F(WebRtcVideoEngine2Test, ChannelWithExternalH264CanChangeToInternalVp8) {
   cricket::FakeWebRtcVideoEncoderFactory encoder_factory;
   encoder_factory.AddSupportedVideoCodecType(webrtc::kVideoCodecH264, "H264");
@@ -632,6 +649,50 @@ TEST_F(WebRtcVideoEngine2Test, ReportSupportedExternalCodecs) {
   EXPECT_EQ("H264", external_codec.name);
 }
 
+TEST_F(WebRtcVideoEngine2Test, RegisterExternalDecodersIfSupported) {
+  cricket::FakeWebRtcVideoDecoderFactory decoder_factory;
+  decoder_factory.AddSupportedVideoCodecType(webrtc::kVideoCodecVP8);
+  std::vector<cricket::VideoCodec> codecs;
+  codecs.push_back(kVp8Codec);
+
+  rtc::scoped_ptr<VideoMediaChannel> channel(
+      SetUpForExternalDecoderFactory(&decoder_factory, codecs));
+
+  EXPECT_TRUE(
+      channel->AddRecvStream(cricket::StreamParams::CreateLegacy(kSsrc)));
+  ASSERT_EQ(1u, decoder_factory.decoders().size());
+
+  // Setting codecs of the same type should not reallocate the decoder.
+  EXPECT_TRUE(channel->SetRecvCodecs(codecs));
+  EXPECT_EQ(1, decoder_factory.GetNumCreatedDecoders());
+
+  // Remove stream previously added to free the external decoder instance.
+  EXPECT_TRUE(channel->RemoveRecvStream(kSsrc));
+  EXPECT_EQ(0u, decoder_factory.decoders().size());
+}
+
+// Verifies that we can set up decoders that are not internally supported.
+TEST_F(WebRtcVideoEngine2Test, RegisterExternalH264DecoderIfSupported) {
+  // TODO(pbos): Do not assume that encoder/decoder support is symmetric. We
+  // can't even query the WebRtcVideoDecoderFactory for supported codecs.
+  // For now we add a FakeWebRtcVideoEncoderFactory to add H264 to supported
+  // codecs.
+  cricket::FakeWebRtcVideoEncoderFactory encoder_factory;
+  encoder_factory.AddSupportedVideoCodecType(webrtc::kVideoCodecH264, "H264");
+  engine_.SetExternalEncoderFactory(&encoder_factory);
+  cricket::FakeWebRtcVideoDecoderFactory decoder_factory;
+  decoder_factory.AddSupportedVideoCodecType(webrtc::kVideoCodecH264);
+  std::vector<cricket::VideoCodec> codecs;
+  codecs.push_back(kH264Codec);
+
+  rtc::scoped_ptr<VideoMediaChannel> channel(
+      SetUpForExternalDecoderFactory(&decoder_factory, codecs));
+
+  EXPECT_TRUE(
+      channel->AddRecvStream(cricket::StreamParams::CreateLegacy(kSsrc)));
+  ASSERT_EQ(1u, decoder_factory.decoders().size());
+}
+
 class WebRtcVideoEngine2BaseTest
     : public VideoEngineTest<cricket::WebRtcVideoEngine2> {
  protected:
@@ -1800,26 +1861,6 @@ TEST_F(WebRtcVideoChannel2Test, DISABLED_SetOptionsWithMaxBitrate) {
   FAIL() << "Not implemented.";  // TODO(pbos): Implement.
 }
 
-TEST_F(WebRtcVideoChannel2Test, DISABLED_ResetCodecOnScreencast) {
-  FAIL() << "Not implemented.";  // TODO(pbos): Implement.
-}
-
-TEST_F(WebRtcVideoChannel2Test, DISABLED_RegisterDecoderIfFactoryIsGiven) {
-  FAIL() << "Not implemented.";  // TODO(pbos): Implement.
-}
-
-TEST_F(WebRtcVideoChannel2Test, DISABLED_DontRegisterDecoderMultipleTimes) {
-  FAIL() << "Not implemented.";  // TODO(pbos): Implement.
-}
-
-TEST_F(WebRtcVideoChannel2Test, DISABLED_DontRegisterDecoderForNonVP8) {
-  FAIL() << "Not implemented.";  // TODO(pbos): Implement.
-}
-
-TEST_F(WebRtcVideoChannel2Test, DISABLED_ExternalCodecIgnored) {
-  FAIL() << "Not implemented.";  // TODO(pbos): Implement.
-}
-
 TEST_F(WebRtcVideoChannel2Test, OnReadyToSendSignalsNetworkState) {
   EXPECT_EQ(webrtc::Call::kNetworkUp, fake_call_->GetNetworkState());