Fix visible size for V4L2 VDA

content/common/gpu/media/v4l2_video_decode_accelerator.cc

Index: content/common/gpu/media/v4l2_video_decode_accelerator.cc
diff --git a/content/common/gpu/media/v4l2_video_decode_accelerator.cc b/content/common/gpu/media/v4l2_video_decode_accelerator.cc
index 7aa737406c9f2f92347c9024e4f03f2146254f8d..5f087e7e429c1c4636fefc8ba7713c1814d29d6a 100644
--- a/content/common/gpu/media/v4l2_video_decode_accelerator.cc
+++ b/content/common/gpu/media/v4l2_video_decode_accelerator.cc
@@ -21,6 +21,7 @@
 #include "content/common/gpu/media/v4l2_video_decode_accelerator.h"
 #include "media/base/media_switches.h"
 #include "media/filters/h264_parser.h"
+#include "ui/gfx/geometry/rect.h"
 #include "ui/gl/scoped_binders.h"
 
 #define NOTIFY_ERROR(x)                        \
@@ -745,6 +746,8 @@ bool V4L2VideoDecodeAccelerator::DecodeBufferInitial(
     // Success! Setup our parameters.
     if (!CreateBuffersForFormat(format))
       return false;
+    if (!GetCropSize(frame_buffer_size_, &frame_visible_size_))
+      frame_visible_size_ = frame_buffer_size_;
 
     // We expect to process the initial buffer once during stream init to
     // configure stream parameters, but will not consume the steam data on that
@@ -1084,9 +1087,8 @@ void V4L2VideoDecodeAccelerator::Dequeue() {
       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,
-                         gfx::Rect(frame_buffer_size_));
+          media::Picture(output_record.picture_id, dqbuf.timestamp.tv_sec,
+                         gfx::Rect(frame_visible_size_));
       pending_picture_ready_.push(
           PictureRecord(output_record.cleared, picture));
       SendPictureReady();
@@ -1546,6 +1548,8 @@ void V4L2VideoDecodeAccelerator::FinishResolutionChange() {
     NOTIFY_ERROR(PLATFORM_FAILURE);
     return;
   }
+  if (!GetCropSize(frame_buffer_size_, &frame_visible_size_))

[Pawel Osciak, 2015/01/29 05:02:04]

Could we call this from GetFormatInfo()?

[kcwu, 2015/01/29 09:33:11]

Done.

+    frame_visible_size_ = frame_buffer_size_;
 
   decoder_state_ = kDecoding;
 
@@ -1658,6 +1662,34 @@ bool V4L2VideoDecodeAccelerator::CreateBuffersForFormat(
   return true;
 }
 
+bool V4L2VideoDecodeAccelerator::GetCropSize(const gfx::Size& buffer_size,
+                                             gfx::Size* crop_size) {
+  DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
+
+  struct v4l2_crop crop_arg;

[Pawel Osciak, 2015/01/29 05:02:04]

memset to 0 please.

[kcwu, 2015/01/29 09:33:10]

Done.

+  crop_arg.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+
+  IOCTL_OR_ERROR_RETURN_FALSE(VIDIOC_G_CROP, &crop_arg);
+
+  gfx::Rect rect(crop_arg.c.left, crop_arg.c.top, crop_arg.c.width,
+                 crop_arg.c.height);
+  DVLOG(3) << "Crop rectangle is " << rect.ToString();

[Pawel Osciak, 2015/01/29 05:02:04]

Let's stop calling this crop and say visible size everywhere instead please.

[kcwu, 2015/01/29 09:33:11]

Done.

+  if (!gfx::Rect(buffer_size).Contains(rect)) {

[Pawel Osciak, 2015/01/29 05:02:04]

Please also check if it's !Empty()

[kcwu, 2015/01/29 09:33:10]

Done.

+    DLOG(ERROR) << "crop rectangle " << rect.ToString()
+                << " is not inside buffer size " << buffer_size.ToString();
+    return false;
+  }
+
+  if (!rect.origin().IsOrigin()) {

[Pawel Osciak, 2015/01/29 05:02:04]

Please add a comment why.

[kcwu, 2015/01/29 09:33:10]

Done.

+    DLOG(ERROR) << "Unexpected crop rectangle " << rect.ToString()
+                << ", top-left is not origin";
+    return false;
+  }
+  *crop_size = rect.size();
+
+  return true;
+}
+
 bool V4L2VideoDecodeAccelerator::CreateInputBuffers() {
   DVLOG(3) << "CreateInputBuffers()";
   // We always run this as we prepare to initialize.
@@ -1978,6 +2010,14 @@ bool V4L2VideoDecodeAccelerator::IsResolutionChangeNecessary() {
     DVLOG(3) << "IsResolutionChangeNecessary(): Resolution change detected";
     return true;
   }
+
+  gfx::Size new_crop_size;
+  if (GetCropSize(new_size, &new_crop_size) &&
+      new_crop_size != frame_visible_size_) {
+    DVLOG(3) << "IsResolutionChangeNecessary(): crop size change detected";

[Pawel Osciak, 2015/01/29 05:02:04]

Crop size does not influence resolution change. If coded size didn't change, a
new crop size does not require reallocating buffers.

[kcwu, 2015/01/29 09:33:11]

Done.

+    return true;
+  }
+
   return false;
 }