Send bytes_used of v4l2 captured frame when video capture

media/video/capture/linux/v4l2_capture_delegate_single_plane.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/video/capture/linux/v4l2_capture_delegate_single_plane.h"
 
 #include <sys/mman.h>
 
 namespace media {
 
@@ skipping 11 matching lines @@
   format->fmt.pix.height = height;
   format->fmt.pix.pixelformat = pixelformat_fourcc;
   return true;
 }
 
 void V4L2CaptureDelegateSinglePlane::FinishFillingV4L2Buffer(
     v4l2_buffer* buffer) const {
   buffer->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 }
 
+void V4L2CaptureDelegateSinglePlane::FetchBytesUsed(
+    const scoped_refptr<BufferTracker>& buffer_tracker,
+    const v4l2_buffer* buffer) const {
+  buffer_tracker->SetPlanePayload(0, buffer->bytesused);
+}
+
 void V4L2CaptureDelegateSinglePlane::SendBuffer(
     const scoped_refptr<BufferTracker>& buffer_tracker,
     const v4l2_format& format) const {
-  const size_t data_length = format.fmt.pix.sizeimage;
-  DCHECK_GE(data_length, capture_format().ImageAllocationSize());
   client()->OnIncomingCapturedData(
       buffer_tracker->GetPlaneStart(0),
-      data_length,
+      buffer_tracker->GetPlanePayload(0),
       capture_format(),
       rotation(),
       base::TimeTicks::Now());
 }
 
 bool V4L2CaptureDelegateSinglePlane::BufferTrackerSPlane::Init(
     int fd,
     const v4l2_buffer& buffer) {
   // Some devices require mmap() to be called with both READ and WRITE.
   // See http://crbug.com/178582.
   void* const start = mmap(NULL, buffer.length, PROT_READ | PROT_WRITE,
                            MAP_SHARED, fd, buffer.m.offset);
   if (start == MAP_FAILED) {
     DLOG(ERROR) << "Error mmap()ing a V4L2 buffer into userspace";
     return false;
   }
   AddMmapedPlane(static_cast<uint8_t*>(start), buffer.length);
   return true;
 }
 
 }  // namespace media