Implement NV12 and GpuMemoryBuffer support for WebCodecs VideoFrames.

This allows for direct planar access to capture buffers on macOS.

R=sandersd

Bug: 1137288, 1141214
Change-Id: I6a4859a807f2d77fd2fdd87c61f8c15dbdfbb0ac
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2536035
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Auto-Submit: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827059}

third_party/blink/renderer/modules/webcodecs/DEPS

@@ -19,6 +19,7 @@ include_rules = [
     "+ui/gfx/color_space.h",
     "+ui/gfx/geometry/rect.h",
     "+ui/gfx/geometry/size.h",
+    "+ui/gfx/gpu_memory_buffer.h",
 ]
 
 specific_include_rules = {

third_party/blink/renderer/modules/webcodecs/plane.cc

@@ -8,16 +8,32 @@
 
 #include "third_party/blink/renderer/platform/bindings/exception_code.h"
 #include "third_party/blink/renderer/platform/bindings/exception_state.h"
+#include "ui/gfx/gpu_memory_buffer.h"
 
 namespace blink {
 
+namespace {
+
+void CopyPlane(const uint8_t* plane,
+               size_t copy_size,
+               size_t trailing_zeros_size,
+               uint8_t* dest) {
+  // Copy plane bytes.
+  memcpy(dest, plane, copy_size);
+
+  // Zero trailing padding bytes.
+  memset(dest + copy_size, 0, trailing_zeros_size);
+}
+
+}  // namespace
+
 Plane::Plane(scoped_refptr<VideoFrameHandle> handle, size_t plane)
     : handle_(std::move(handle)), plane_(plane) {
 #if DCHECK_IS_ON()
   // Validate the plane index, but only if the handle is valid.
   auto local_frame = handle_->frame();
   if (local_frame) {
-    DCHECK(local_frame->IsMappable());
+    DCHECK(local_frame->IsMappable() || local_frame->HasGpuMemoryBuffer());
     DCHECK_LT(plane, local_frame->layout().num_planes());
   }
 #endif  // DCHECK_IS_ON()
@@ -86,11 +102,21 @@ void Plane::readInto(MaybeShared<DOMArrayBufferView> dst,
     return;
   }
 
-  // Copy plane bytes.
-  memcpy(base, local_frame->data(plane_), copy_size);
+  if (local_frame->IsMappable()) {
+    CopyPlane(local_frame->data(plane_), copy_size, trailing_zeros_size, base);
+    return;
+  }
 
-  // Zero trailing padding bytes.
-  memset(base + copy_size, 0, trailing_zeros_size);
+  DCHECK(local_frame->HasGpuMemoryBuffer());
+  auto* gmb = local_frame->GetGpuMemoryBuffer();
+  if (!gmb->Map()) {
+    exception_state.ThrowDOMException(DOMExceptionCode::kInvalidStateError,
+                                      "Could not map video frame into memory.");
+    return;
+  }
+  CopyPlane(static_cast<const uint8_t*>(gmb->memory(plane_)), copy_size,
+            trailing_zeros_size, base);
+  gmb->Unmap();
 }
 
 }  // namespace blink

third_party/blink/renderer/modules/webcodecs/video_frame.cc

@@ -219,10 +219,12 @@ VideoFrame* VideoFrame::Create(ImageBitmap* source,
 
 // static
 bool VideoFrame::IsSupportedPlanarFormat(media::VideoFrame* frame) {
-  // For now only I420 in CPU memory is supported.
-  return frame && frame->IsMappable() &&
-         frame->format() == media::PIXEL_FORMAT_I420 &&
-         frame->layout().num_planes() == 3;
+  // For now only I420 or NV12 in CPU or GPU memory is supported.
+  return frame && (frame->IsMappable() || frame->HasGpuMemoryBuffer()) &&
+         ((frame->format() == media::PIXEL_FORMAT_I420 &&
+           frame->layout().num_planes() == 3) ||
+          (frame->format() == media::PIXEL_FORMAT_NV12 &&
+           frame->layout().num_planes() == 2));
 }
 
 String VideoFrame::format() const {
@@ -233,6 +235,8 @@ String VideoFrame::format() const {
   switch (local_frame->format()) {
     case media::PIXEL_FORMAT_I420:
       return V8VideoPixelFormat(V8VideoPixelFormat::Enum::kI420);
+    case media::PIXEL_FORMAT_NV12:
+      return V8VideoPixelFormat(V8VideoPixelFormat::Enum::kNV12);
 
     default:
       NOTREACHED();

third_party/blink/renderer/modules/webcodecs/video_pixel_format.idl

@@ -5,6 +5,9 @@
 // https://github.com/WICG/web-codecs
 
 enum VideoPixelFormat {
-    // 4:2:0 subsampled planar YUV
-    "I420"
+    // 4:2:0 subsampled 3 plane Y,U,V
+    "I420",
+
+    // 4:2:0 subsampled 2 plane Y,UV
+    "NV12",
 };