diff --git a/webrtc/modules/video_coding/codecs/vp8/simulcast_unittest.h b/webrtc/modules/video_coding/codecs/vp8/simulcast_unittest.h
index 4925b93238..b3f58e20b1 100644
--- a/webrtc/modules/video_coding/codecs/vp8/simulcast_unittest.h
+++ b/webrtc/modules/video_coding/codecs/vp8/simulcast_unittest.h
@@ -616,6 +616,16 @@ class TestVp8Simulcast : public ::testing::Test {
     EXPECT_EQ(0, encoder_->InitEncode(&settings_, 1, 1200));
     encoder_->SetRates(settings_.startBitrate, 30);
     ExpectStreams(kKeyFrame, 1);
+    // Resize |input_frame_| to the new resolution.
+    half_width = (settings_.width + 1) / 2;
+    input_frame_.CreateEmptyFrame(settings_.width, settings_.height,
+                                  settings_.width, half_width, half_width);
+    memset(input_frame_.buffer(kYPlane), 0,
+        input_frame_.allocated_size(kYPlane));
+    memset(input_frame_.buffer(kUPlane), 0,
+        input_frame_.allocated_size(kUPlane));
+    memset(input_frame_.buffer(kVPlane), 0,
+        input_frame_.allocated_size(kVPlane));
     EXPECT_EQ(0, encoder_->Encode(input_frame_, NULL, &frame_types));
   }
 
diff --git a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
index 9c9c22d21d..34862a46fa 100644
--- a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
+++ b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
@@ -19,6 +19,7 @@
 #include "libyuv/scale.h"  // NOLINT
 #include "libyuv/convert.h"  // NOLINT
 
+#include "webrtc/base/checks.h"
 #include "webrtc/common.h"
 #include "webrtc/common_types.h"
 #include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
@@ -743,6 +744,13 @@ int VP8EncoderImpl::Encode(
       return ret;
   }
 
+  // Since we are extracting raw pointers from |input_image| to
+  // |raw_images_[0]|, the resolution of these frames must match. Note that
+  // |input_image| might be scaled from |frame|. In that case, the resolution of
+  // |raw_images_[0]| should have been updated in UpdateCodecFrameSize.
+  DCHECK_EQ(input_image.width(), static_cast<int>(raw_images_[0].d_w));
+  DCHECK_EQ(input_image.height(), static_cast<int>(raw_images_[0].d_h));
+
   // Image in vpx_image_t format.
   // Input image is const. VP8's raw image is not defined as const.
   raw_images_[0].planes[VPX_PLANE_Y] =
diff --git a/webrtc/modules/video_coding/codecs/vp9/vp9_impl.cc b/webrtc/modules/video_coding/codecs/vp9/vp9_impl.cc
index 0f10c762d0..a6a7ecd4e0 100644
--- a/webrtc/modules/video_coding/codecs/vp9/vp9_impl.cc
+++ b/webrtc/modules/video_coding/codecs/vp9/vp9_impl.cc
@@ -21,6 +21,7 @@
 #include "vpx/vp8cx.h"
 #include "vpx/vp8dx.h"
 
+#include "webrtc/base/checks.h"
 #include "webrtc/common.h"
 #include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
 #include "webrtc/modules/interface/module_common_types.h"
@@ -265,6 +266,8 @@ int VP9EncoderImpl::Encode(const I420VideoFrame& input_image,
   if (frame_types && frame_types->size() > 0) {
     frame_type = (*frame_types)[0];
   }
+  DCHECK_EQ(input_image.width(), static_cast<int>(raw_->d_w));
+  DCHECK_EQ(input_image.height(), static_cast<int>(raw_->d_h));
   // Image in vpx_image_t format.
   // Input image is const. VPX's raw image is not defined as const.
   raw_->planes[VPX_PLANE_Y] = const_cast<uint8_t*>(input_image.buffer(kYPlane));