diff --git a/webrtc/modules/video_coding/main/source/codec_database.cc b/webrtc/modules/video_coding/main/source/codec_database.cc
index 6ca7d9dd09..98dcc3b579 100644
--- a/webrtc/modules/video_coding/main/source/codec_database.cc
+++ b/webrtc/modules/video_coding/main/source/codec_database.cc
@@ -640,6 +640,10 @@ bool VCMCodecDataBase::SupportsRenderScheduling() const {
   return render_timing;
 }
 
+bool VCMCodecDataBase::MatchesCurrentResolution(int width, int height) const {
+  return send_codec_.width == width && send_codec_.height == height;
+}
+
 VCMGenericDecoder* VCMCodecDataBase::CreateAndInitDecoder(
     uint8_t payload_type,
     VideoCodec* new_codec,
diff --git a/webrtc/modules/video_coding/main/source/codec_database.h b/webrtc/modules/video_coding/main/source/codec_database.h
index 762a909147..7078e29522 100644
--- a/webrtc/modules/video_coding/main/source/codec_database.h
+++ b/webrtc/modules/video_coding/main/source/codec_database.h
@@ -146,6 +146,8 @@ class VCMCodecDataBase {
   // the encoded frames.
   bool SupportsRenderScheduling() const;
 
+  bool MatchesCurrentResolution(int width, int height) const;
+
  private:
   typedef std::map<uint8_t, VCMDecoderMapItem*> DecoderMap;
   typedef std::map<uint8_t, VCMExtDecoderMapItem*> ExternalDecoderMap;
diff --git a/webrtc/modules/video_coding/main/source/video_sender.cc b/webrtc/modules/video_coding/main/source/video_sender.cc
index bfd22bd028..5a4ed1f9d7 100644
--- a/webrtc/modules/video_coding/main/source/video_sender.cc
+++ b/webrtc/modules/video_coding/main/source/video_sender.cc
@@ -370,6 +370,13 @@ int32_t VideoSender::AddVideoFrame(const I420VideoFrame& videoFrame,
     return VCM_OK;
   }
   _mediaOpt.UpdateContentData(contentMetrics);
+  // TODO(pbos): Make sure setting send codec is synchronized with video
+  // processing so frame size always matches.
+  if (!_codecDataBase.MatchesCurrentResolution(videoFrame.width(),
+                                               videoFrame.height())) {
+    LOG(LS_ERROR) << "Incoming frame doesn't match set resolution. Dropping.";
+    return VCM_PARAMETER_ERROR;
+  }
   int32_t ret =
       _encoder->Encode(videoFrame, codecSpecificInfo, _nextFrameTypes);
   recorder_->Add(videoFrame);
diff --git a/webrtc/modules/video_coding/main/source/video_sender_unittest.cc b/webrtc/modules/video_coding/main/source/video_sender_unittest.cc
index de596d8e82..f28b9dfba4 100644
--- a/webrtc/modules/video_coding/main/source/video_sender_unittest.cc
+++ b/webrtc/modules/video_coding/main/source/video_sender_unittest.cc
@@ -70,12 +70,17 @@ MATCHER_P(MatchesVp8StreamInfo, expected, "") {
 
 class EmptyFrameGenerator : public FrameGenerator {
  public:
+  EmptyFrameGenerator(int width, int height) : width_(width), height_(height) {}
   I420VideoFrame* NextFrame() override {
     frame_.reset(new I420VideoFrame());
+    frame_->CreateEmptyFrame(width_, height_, width_, (width_ + 1) / 2,
+                             (width_ + 1) / 2);
     return frame_.get();
   }
 
  private:
+  const int width_;
+  const int height_;
   rtc::scoped_ptr<I420VideoFrame> frame_;
 };
 
@@ -199,7 +204,6 @@ class TestVideoSenderWithMockEncoder : public TestVideoSender {
 
   void SetUp() override {
     TestVideoSender::SetUp();
-    generator_.reset(new EmptyFrameGenerator());
     EXPECT_EQ(
         0,
         sender_->RegisterExternalEncoder(&encoder_, kUnusedPayloadType, false));
@@ -217,6 +221,8 @@ class TestVideoSenderWithMockEncoder : public TestVideoSender {
     ConfigureStream(
         kDefaultWidth, kDefaultHeight, 1200, &settings_.simulcastStream[2]);
     settings_.plType = kUnusedPayloadType;  // Use the mocked encoder.
+    generator_.reset(
+        new EmptyFrameGenerator(settings_.width, settings_.height));
     EXPECT_EQ(0, sender_->RegisterSendCodec(&settings_, 1, 1200));
   }