V4L2VideoEncodeAccelerator: increase the number of input buffers to 2.

media/gpu/v4l2_video_encode_accelerator.cc

 // Copyright 2014 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/gpu/v4l2_video_encode_accelerator.h"
 
 #include <fcntl.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <string.h>
@@ skipping 1126 matching lines @@
 bool V4L2VideoEncodeAccelerator::CreateInputBuffers() {
   DVLOG(3) << "CreateInputBuffers()";
   // This function runs on encoder_thread_ after output buffers have been
   // provided by the client.
   DCHECK(encoder_thread_.task_runner()->BelongsToCurrentThread());
   DCHECK(!input_streamon_);
 
   struct v4l2_requestbuffers reqbufs;
   memset(&reqbufs, 0, sizeof(reqbufs));
   // Driver will modify to the appropriate number of buffers.
-  reqbufs.count = 1;
+  reqbufs.count = kInputBufferCount;
   reqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
   // TODO(posciak): Once we start doing zero-copy, we should decide based on
   // the current pipeline setup which memory type to use. This should probably
   // be decided based on an argument to Initialize().
   if (image_processor_.get())
     input_memory_type_ = V4L2_MEMORY_DMABUF;
   else
     input_memory_type_ = V4L2_MEMORY_USERPTR;
 
   reqbufs.memory = input_memory_type_;
@@ skipping 81 matching lines @@
   reqbufs.count = 0;
   reqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
   reqbufs.memory = V4L2_MEMORY_MMAP;
   IOCTL_OR_LOG_ERROR(VIDIOC_REQBUFS, &reqbufs);
 
   output_buffer_map_.clear();
   free_output_buffers_.clear();
 }
 
 }  // namespace media