V4L2VDA: Generalize EGLImage import and query driver for output formats.

content/common/gpu/media/v4l2_video_decode_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 <dlfcn.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <sys/eventfd.h>
@@ skipping 170 matching lines @@
       output_buffer_queued_count_(0),
       output_dpb_size_(0),
       output_planes_count_(0),
       picture_clearing_count_(0),
       pictures_assigned_(false, false),
       device_poll_thread_("V4L2DevicePollThread"),
       make_context_current_(make_context_current),
       egl_display_(egl_display),
       egl_context_(egl_context),
       video_profile_(media::VIDEO_CODEC_PROFILE_UNKNOWN),
+      output_format_fourcc_(0),
       weak_this_factory_(this) {
   weak_this_ = weak_this_factory_.GetWeakPtr();
 }
 
 V4L2VideoDecodeAccelerator::~V4L2VideoDecodeAccelerator() {
   DCHECK(!decoder_thread_.IsRunning());
   DCHECK(!device_poll_thread_.IsRunning());
 
   DestroyInputBuffers();
   DestroyOutputBuffers();
@@ skipping 61 matching lines @@
   if ((caps.capabilities & kCapsRequired) != kCapsRequired) {
     LOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP"
         ", caps check failed: 0x" << std::hex << caps.capabilities;
     NOTIFY_ERROR(PLATFORM_FAILURE);
     return false;
   }
 
   if (!CreateInputBuffers())
     return false;
 
-  // Output format has to be setup before streaming starts.
-  struct v4l2_format format;
-  memset(&format, 0, sizeof(format));
-  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  uint32 output_format_fourcc = device_->PreferredOutputFormat();
-  if (output_format_fourcc == 0) {
-    // TODO(posciak): We should enumerate available output formats, as well as
-    // take into account formats that the client is ready to accept.
+  if (!SetupOutputFormat())
     return false;
-  }
-  format.fmt.pix_mp.pixelformat = output_format_fourcc;
-  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_S_FMT, &format);
 
   // Subscribe to the resolution change event.
   struct v4l2_event_subscription sub;
   memset(&sub, 0, sizeof(sub));
   sub.type = V4L2_EVENT_RESOLUTION_CHANGE;
   IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_SUBSCRIBE_EVENT, &sub);
 
-  // Initialize format-specific bits.
   if (video_profile_ >= media::H264PROFILE_MIN &&
       video_profile_ <= media::H264PROFILE_MAX) {
     decoder_h264_parser_.reset(new media::H264Parser());
   }
 
   if (!decoder_thread_.Start()) {
     LOG(ERROR) << "Initialize(): decoder thread failed to start";
     NOTIFY_ERROR(PLATFORM_FAILURE);
     return false;
   }
@@ skipping 54 matching lines @@
     DCHECK_EQ(output_record.egl_image, EGL_NO_IMAGE_KHR);
     DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
     DCHECK_EQ(output_record.picture_id, -1);
     DCHECK_EQ(output_record.cleared, false);
 
     EGLImageKHR egl_image = device_->CreateEGLImage(egl_display_,
                                                     egl_context_,
                                                     buffers[i].texture_id(),
                                                     frame_buffer_size_,
                                                     i,
+                                                    output_format_fourcc_,
                                                     output_planes_count_);
     if (egl_image == EGL_NO_IMAGE_KHR) {
       LOG(ERROR) << "AssignPictureBuffers(): could not create EGLImageKHR";
       // Ownership of EGLImages allocated in previous iterations of this loop
       // has been transferred to output_buffer_map_. After we error-out here
       // the destructor will handle their cleanup.
       NOTIFY_ERROR(PLATFORM_FAILURE);
       return;
     }
 
@@ skipping 700 matching lines @@
       PLOG(ERROR) << "Dequeue(): ioctl() failed: VIDIOC_DQBUF";
       NOTIFY_ERROR(PLATFORM_FAILURE);
       return;
     }
     OutputRecord& output_record = output_buffer_map_[dqbuf.index];
     DCHECK(output_record.at_device);
     DCHECK(!output_record.at_client);
     DCHECK_NE(output_record.egl_image, EGL_NO_IMAGE_KHR);
     DCHECK_NE(output_record.picture_id, -1);
     output_record.at_device = false;
-    if (dqbuf.m.planes[0].bytesused + dqbuf.m.planes[1].bytesused == 0) {
+    if (dqbuf.m.planes[0].bytesused == 0) {
       // This is an empty output buffer returned as part of a flush.
       free_output_buffers_.push(dqbuf.index);
     } else {
       DCHECK_GE(dqbuf.timestamp.tv_sec, 0);
       output_record.at_client = true;
       DVLOG(3) << "Dequeue(): returning input_id=" << dqbuf.timestamp.tv_sec
                << " as picture_id=" << output_record.picture_id;
       const media::Picture& picture =
           media::Picture(output_record.picture_id,
                          dqbuf.timestamp.tv_sec,
@@ skipping 614 matching lines @@
       PLOG(ERROR) << "CreateInputBuffers(): mmap() failed";
       return false;
     }
     input_buffer_map_[i].address = address;
     input_buffer_map_[i].length = buffer.m.planes[0].length;
   }
 
   return true;
 }
 
+bool V4L2VideoDecodeAccelerator::SetupOutputFormat() {
+  // We have to set up the format for output beforehand, because the driver may
+  // not allow changing it once we start streaming; whether it can support our
+  // chosen output format or not may depend on the input format.
+  struct v4l2_fmtdesc fmtdesc;
+  memset(&fmtdesc, 0, sizeof(fmtdesc));
+  fmtdesc.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  while (device_->Ioctl(VIDIOC_ENUM_FMT, &fmtdesc) == 0) {
+    if (device_->CanCreateEGLImageFrom(fmtdesc.pixelformat)) {
+      output_format_fourcc_ = fmtdesc.pixelformat;
+      break;
+    }
+    ++fmtdesc.index;
+  }
+
+  if (output_format_fourcc_ == 0) {
+    LOG(ERROR) << "Could not find a usable output format";
+    return false;
+  }
+
+  // Just set the fourcc for output; resolution, etc., will come from the
+  // driver once it extracts it from the stream.
+  struct v4l2_format format;
+  memset(&format, 0, sizeof(format));
+  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  format.fmt.pix_mp.pixelformat = output_format_fourcc_;
+  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_S_FMT, &format);
+
+  return true;
+}
+
 bool V4L2VideoDecodeAccelerator::CreateOutputBuffers() {
   DVLOG(3) << "CreateOutputBuffers()";
   DCHECK(decoder_state_ == kInitialized ||
          decoder_state_ == kChangingResolution);
   DCHECK(!output_streamon_);
   DCHECK(output_buffer_map_.empty());
 
   // Number of output buffers we need.
   struct v4l2_control ctrl;
   memset(&ctrl, 0, sizeof(ctrl));
@@ skipping 203 matching lines @@
   gfx::Size new_size(base::checked_cast<int>(format.fmt.pix_mp.width),
                      base::checked_cast<int>(format.fmt.pix_mp.height));
   if (frame_buffer_size_ != new_size) {
     DVLOG(3) << "IsResolutionChangeNecessary(): Resolution change detected";
     return true;
   }
   return false;
 }
 
 }  // namespace content