diff --git a/dom/media/ImageToI420.cpp b/dom/media/ImageConversion.cpp
similarity index 75%
rename from dom/media/ImageToI420.cpp
rename to dom/media/ImageConversion.cpp
index 0f7976cb6311..ea8d25827997 100644
--- a/dom/media/ImageToI420.cpp
+++ b/dom/media/ImageConversion.cpp
@@ -3,10 +3,11 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#include "ImageToI420.h"
+#include "ImageConversion.h"
 
 #include "ImageContainer.h"
 #include "libyuv/convert.h"
+#include "libyuv/convert_from_argb.h"
 #include "mozilla/dom/ImageBitmapBinding.h"
 #include "mozilla/dom/ImageUtils.h"
 #include "mozilla/gfx/Point.h"
@@ -151,4 +152,56 @@ nsresult ConvertToI420(Image* aImage, uint8_t* aDestY, int aDestStrideY,
   }
 }
 
+nsresult ConvertToNV12(layers::Image* aImage, uint8_t* aDestY, int aDestStrideY,
+                       uint8_t* aDestUV, int aDestStrideUV) {
+  if (!aImage->IsValid()) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  if (const PlanarYCbCrData* data = GetPlanarYCbCrData(aImage)) {
+    const ImageUtils imageUtils(aImage);
+    Maybe<dom::ImageBitmapFormat> format = imageUtils.GetFormat();
+    if (format.isNothing()) {
+      MOZ_ASSERT_UNREACHABLE("YUV format conversion not implemented");
+      return NS_ERROR_NOT_IMPLEMENTED;
+    }
+
+    if (format.value() != ImageBitmapFormat::YUV420P) {
+      NS_WARNING("ConvertToNV12: Convert YUV data in I420 only");
+      return NS_ERROR_NOT_IMPLEMENTED;
+    }
+
+    return MapRv(libyuv::I420ToNV12(
+        data->mYChannel, data->mYStride, data->mCbChannel, data->mCbCrStride,
+        data->mCrChannel, data->mCbCrStride, aDestY, aDestStrideY, aDestUV,
+        aDestStrideUV, aImage->GetSize().width, aImage->GetSize().height));
+  }
+
+  RefPtr<SourceSurface> surf = GetSourceSurface(aImage);
+  if (!surf) {
+    return NS_ERROR_FAILURE;
+  }
+
+  RefPtr<DataSourceSurface> data = surf->GetDataSurface();
+  if (!data) {
+    return NS_ERROR_FAILURE;
+  }
+
+  DataSourceSurface::ScopedMap map(data, DataSourceSurface::READ);
+  if (!map.IsMapped()) {
+    return NS_ERROR_FAILURE;
+  }
+
+  if (surf->GetFormat() != SurfaceFormat::B8G8R8A8 &&
+      surf->GetFormat() != SurfaceFormat::B8G8R8X8) {
+    NS_WARNING("ConvertToNV12: Convert SurfaceFormat in BGR* only");
+    return NS_ERROR_NOT_IMPLEMENTED;
+  }
+
+  return MapRv(
+      libyuv::ARGBToNV12(static_cast<uint8_t*>(map.GetData()), map.GetStride(),
+                         aDestY, aDestStrideY, aDestUV, aDestStrideUV,
+                         aImage->GetSize().width, aImage->GetSize().height));
+}
+
 }  // namespace mozilla
diff --git a/dom/media/ImageToI420.h b/dom/media/ImageConversion.h
similarity index 77%
rename from dom/media/ImageToI420.h
rename to dom/media/ImageConversion.h
index 24a66ebc9f6f..8f1396f9e987 100644
--- a/dom/media/ImageToI420.h
+++ b/dom/media/ImageConversion.h
@@ -21,6 +21,12 @@ nsresult ConvertToI420(layers::Image* aImage, uint8_t* aDestY, int aDestStrideY,
                        uint8_t* aDestU, int aDestStrideU, uint8_t* aDestV,
                        int aDestStrideV);
 
+/**
+ * Converts aImage to an NV12 image and writes it to the given buffers.
+ */
+nsresult ConvertToNV12(layers::Image* aImage, uint8_t* aDestY, int aDestStrideY,
+                       uint8_t* aDestUV, int aDestStrideUV);
+
 }  // namespace mozilla
 
 #endif /* ImageToI420Converter_h */
diff --git a/dom/media/VideoFrameConverter.h b/dom/media/VideoFrameConverter.h
index 31b310495544..43a4075b0459 100644
--- a/dom/media/VideoFrameConverter.h
+++ b/dom/media/VideoFrameConverter.h
@@ -7,7 +7,7 @@
 #define VideoFrameConverter_h
 
 #include "ImageContainer.h"
-#include "ImageToI420.h"
+#include "ImageConversion.h"
 #include "Pacer.h"
 #include "PerformanceRecorder.h"
 #include "VideoSegment.h"
diff --git a/dom/media/encoder/VP8TrackEncoder.cpp b/dom/media/encoder/VP8TrackEncoder.cpp
index 0c7f3de1f48f..36680b65527c 100644
--- a/dom/media/encoder/VP8TrackEncoder.cpp
+++ b/dom/media/encoder/VP8TrackEncoder.cpp
@@ -9,7 +9,7 @@
 #include <vpx/vpx_encoder.h>
 
 #include "DriftCompensation.h"
-#include "ImageToI420.h"
+#include "ImageConversion.h"
 #include "mozilla/gfx/2D.h"
 #include "prsystem.h"
 #include "VideoSegment.h"
diff --git a/dom/media/moz.build b/dom/media/moz.build
index 1def6333f29e..7f256387c793 100644
--- a/dom/media/moz.build
+++ b/dom/media/moz.build
@@ -157,7 +157,7 @@ EXPORTS += [
     "FileBlockCache.h",
     "ForwardedInputTrack.h",
     "FrameStatistics.h",
-    "ImageToI420.h",
+    "ImageConversion.h",
     "Intervals.h",
     "MediaCache.h",
     "MediaContainerType.h",
@@ -282,7 +282,7 @@ UNIFIED_SOURCES += [
     "GetUserMediaRequest.cpp",
     "GraphDriver.cpp",
     "GraphRunner.cpp",
-    "ImageToI420.cpp",
+    "ImageConversion.cpp",
     "MediaCache.cpp",
     "MediaContainerType.cpp",
     "MediaDecoder.cpp",
diff --git a/dom/media/platforms/ffmpeg/FFmpegVideoEncoder.cpp b/dom/media/platforms/ffmpeg/FFmpegVideoEncoder.cpp
index 686fbcc44931..83b0f98c5b32 100644
--- a/dom/media/platforms/ffmpeg/FFmpegVideoEncoder.cpp
+++ b/dom/media/platforms/ffmpeg/FFmpegVideoEncoder.cpp
@@ -15,7 +15,7 @@
 #include "libavutil/pixfmt.h"
 #include "mozilla/dom/ImageUtils.h"
 #include "nsPrintfCString.h"
-#include "ImageToI420.h"
+#include "ImageConversion.h"
 #include "libyuv.h"
 #include "FFmpegRuntimeLinker.h"
 
diff --git a/dom/media/platforms/wmf/WMFMediaDataEncoder.cpp b/dom/media/platforms/wmf/WMFMediaDataEncoder.cpp
index 3bc532d499fd..fcacedbd0569 100644
--- a/dom/media/platforms/wmf/WMFMediaDataEncoder.cpp
+++ b/dom/media/platforms/wmf/WMFMediaDataEncoder.cpp
@@ -7,6 +7,7 @@
 #include "WMFMediaDataEncoder.h"
 
 #include "ImageContainer.h"
+#include "ImageConversion.h"
 #include "MFTEncoder.h"
 #include "PlatformEncoderModule.h"
 #include "TimeUnits.h"
@@ -37,8 +38,7 @@ RefPtr<InitPromise> WMFMediaDataEncoder::Init() {
   return InvokeAsync(mTaskQueue, this, __func__,
                      &WMFMediaDataEncoder::ProcessInit);
 }
-RefPtr<EncodePromise> WMFMediaDataEncoder::Encode(
-    const MediaData* aSample) {
+RefPtr<EncodePromise> WMFMediaDataEncoder::Encode(const MediaData* aSample) {
   MOZ_ASSERT(aSample);
 
   RefPtr<const VideoData> sample(aSample->As<const VideoData>());
@@ -67,8 +67,7 @@ RefPtr<ShutdownPromise> WMFMediaDataEncoder::Shutdown() {
                        return ShutdownPromise::CreateAndResolve(true, __func__);
                      });
 }
-RefPtr<GenericPromise> WMFMediaDataEncoder::SetBitrate(
-    uint32_t aBitsPerSec) {
+RefPtr<GenericPromise> WMFMediaDataEncoder::SetBitrate(uint32_t aBitsPerSec) {
   return InvokeAsync(
       mTaskQueue, __func__,
       [self = RefPtr<WMFMediaDataEncoder>(this), aBitsPerSec]() {
@@ -162,7 +161,8 @@ void WMFMediaDataEncoder::FillConfigData() {
           : nullptr;
 }
 
-RefPtr<EncodePromise> WMFMediaDataEncoder::ProcessEncode(RefPtr<const VideoData>&& aSample) {
+RefPtr<EncodePromise> WMFMediaDataEncoder::ProcessEncode(
+    RefPtr<const VideoData>&& aSample) {
   AssertOnTaskQueue();
   MOZ_ASSERT(mEncoder);
   MOZ_ASSERT(aSample);
@@ -196,43 +196,110 @@ already_AddRefed<IMFSample> WMFMediaDataEncoder::ConvertToNV12InputSample(
   AssertOnTaskQueue();
   MOZ_ASSERT(mEncoder);
 
-  const layers::PlanarYCbCrImage* image = aData->mImage->AsPlanarYCbCrImage();
-  // TODO: Take care non planar Y-Cb-Cr image (Bug 1881647).
-  NS_ENSURE_TRUE(image, nullptr);
+  struct NV12Info {
+    int32_t mYStride = 0;
+    int32_t mUVStride = 0;
+    size_t mYLength = 0;
+    size_t mBufferLength = 0;
+  } info;
 
-  const layers::PlanarYCbCrData* yuv = image->GetData();
-  auto ySize = yuv->YDataSize();
-  auto cbcrSize = yuv->CbCrDataSize();
-  size_t yLength = yuv->mYStride * ySize.height;
-  size_t length = yLength + (yuv->mCbCrStride * cbcrSize.height * 2);
+  if (const layers::PlanarYCbCrImage* image =
+          aData->mImage->AsPlanarYCbCrImage()) {
+    // Assume this is I420. If it's not, the whole process fails in
+    // ConvertToNV12 below.
+    const layers::PlanarYCbCrData* yuv = image->GetData();
+    info.mYStride = yuv->mYStride;
+    info.mUVStride = yuv->mCbCrStride * 2;
+    info.mYLength = info.mYStride * yuv->YDataSize().height;
+    info.mBufferLength =
+        info.mYLength + (info.mUVStride * yuv->CbCrDataSize().height);
+  } else {
+    info.mYStride = aData->mImage->GetSize().width;
+    info.mUVStride = info.mYStride;
+
+    const int32_t yHeight = aData->mImage->GetSize().height;
+    const int32_t uvHeight = yHeight / 2;
+
+    CheckedInt<size_t> yLength(info.mYStride);
+    yLength *= yHeight;
+    if (!yLength.isValid()) {
+      WMF_ENC_LOGE("yLength overflows");
+      return nullptr;
+    }
+    info.mYLength = yLength.value();
+
+    CheckedInt<size_t> uvLength(info.mUVStride);
+    uvLength *= uvHeight;
+    if (!uvLength.isValid()) {
+      WMF_ENC_LOGE("uvLength overflows");
+      return nullptr;
+    }
+
+    CheckedInt<size_t> length(yLength);
+    length += uvLength;
+    if (!length.isValid()) {
+      WMF_ENC_LOGE("length overflows");
+      return nullptr;
+    }
+    info.mBufferLength = length.value();
+  }
 
   RefPtr<IMFSample> input;
-  HRESULT hr = mEncoder->CreateInputSample(&input, length);
-  NS_ENSURE_TRUE(SUCCEEDED(hr), nullptr);
+  HRESULT hr = mEncoder->CreateInputSample(&input, info.mBufferLength);
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("CreateInputSample: error = 0x%lX, %ls", hr,
+                 error.ErrorMessage());
+    return nullptr;
+  }
 
   RefPtr<IMFMediaBuffer> buffer;
   hr = input->GetBufferByIndex(0, getter_AddRefs(buffer));
-  NS_ENSURE_TRUE(SUCCEEDED(hr), nullptr);
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("GetBufferByIndex: error = 0x%lX, %ls", hr,
+                 error.ErrorMessage());
+    return nullptr;
+  }
 
-  hr = buffer->SetCurrentLength(length);
-  NS_ENSURE_TRUE(SUCCEEDED(hr), nullptr);
+  hr = buffer->SetCurrentLength(info.mBufferLength);
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("SetCurrentLength: error = 0x%lX, %ls", hr,
+                 error.ErrorMessage());
+    return nullptr;
+  }
 
   LockBuffer lockBuffer(buffer);
-  NS_ENSURE_TRUE(SUCCEEDED(lockBuffer.Result()), nullptr);
+  hr = lockBuffer.Result();
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("LockBuffer: error = 0x%lX, %ls", hr, error.ErrorMessage());
+    return nullptr;
+  }
 
-  // TODO: Take care non I420 image (Bug 1881647).
-  bool ok = libyuv::I420ToNV12(
-                yuv->mYChannel, yuv->mYStride, yuv->mCbChannel,
-                yuv->mCbCrStride, yuv->mCrChannel, yuv->mCbCrStride,
-                lockBuffer.Data(), yuv->mYStride, lockBuffer.Data() + yLength,
-                yuv->mCbCrStride * 2, ySize.width, ySize.height) == 0;
-  NS_ENSURE_TRUE(ok, nullptr);
+  nsresult rv =
+      ConvertToNV12(aData->mImage, lockBuffer.Data(), info.mYStride,
+                    lockBuffer.Data() + info.mYLength, info.mUVStride);
+  if (NS_FAILED(rv)) {
+    WMF_ENC_LOGE("Failed to convert to NV12");
+    return nullptr;
+  }
 
   hr = input->SetSampleTime(UsecsToHNs(aData->mTime.ToMicroseconds()));
-  NS_ENSURE_TRUE(SUCCEEDED(hr), nullptr);
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("SetSampleTime: error = 0x%lX, %ls", hr, error.ErrorMessage());
+    return nullptr;
+  }
 
   hr = input->SetSampleDuration(UsecsToHNs(aData->mDuration.ToMicroseconds()));
-  NS_ENSURE_TRUE(SUCCEEDED(hr), nullptr);
+  if (FAILED(hr)) {
+    _com_error error(hr);
+    WMF_ENC_LOGE("SetSampleDuration: error = 0x%lX, %ls", hr,
+                 error.ErrorMessage());
+    return nullptr;
+  }
 
   return input.forget();
 }
diff --git a/testing/web-platform/meta/webcodecs/video-encoder-h264.https.any.js.ini b/testing/web-platform/meta/webcodecs/video-encoder-h264.https.any.js.ini
index e0d96bb0ff48..ca8a1de2092c 100644
--- a/testing/web-platform/meta/webcodecs/video-encoder-h264.https.any.js.ini
+++ b/testing/web-platform/meta/webcodecs/video-encoder-h264.https.any.js.ini
@@ -1,7 +1,7 @@
 [video-encoder-h264.https.any.html?main]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED
       if os == "mac": PASS
@@ -9,7 +9,7 @@
 [video-encoder-h264.https.any.html?baseline]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "mac": PASS
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED
@@ -17,7 +17,7 @@
 [video-encoder-h264.https.any.worker.html?baseline]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "mac": PASS
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED
@@ -25,7 +25,7 @@
 [video-encoder-h264.https.any.html?high]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "mac": PASS
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED
@@ -33,7 +33,7 @@
 [video-encoder-h264.https.any.worker.html?main]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "mac": PASS
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED
@@ -41,7 +41,7 @@
 [video-encoder-h264.https.any.worker.html?high]
   [Test that encoding with a specific H264 profile actually produces that profile.]
     expected:
-      if os == "win": FAIL
+      if os == "win": [FAIL, PASS]
       if os == "android": PRECONDITION_FAILED
       if os == "mac": PASS
       if os == "linux" and version == "Ubuntu 18.04": PRECONDITION_FAILED