Add accelerated video decoder interface, VP8 and H.264 implementations and hook up to V4L2SVDA.

content/common/gpu/media/h264_decoder.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.

[Owen Lin, 2015/01/08 15:42:06]

2015? 
Remove (c)?

[Pawel Osciak, 2015/01/12 07:18:19]

This is basically a copy of vaapi_h264_decoder, so keeping the copyright from
the old file.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_COMMON_GPU_MEDIA_H264_DECODER_H_
+#define CONTENT_COMMON_GPU_MEDIA_H264_DECODER_H_
+
+#include <vector>
+
+#include "base/callback_forward.h"
+#include "base/memory/linked_ptr.h"

[Owen Lin, 2015/01/08 15:42:06]

Are the above two includes not used?

[Pawel Osciak, 2015/01/12 07:18:19]

Done.

+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop_proxy.h"
+#include "content/common/content_export.h"
+#include "content/common/gpu/media/accelerated_video_decoder.h"
+#include "content/common/gpu/media/h264_dpb.h"
+#include "media/base/limits.h"
+#include "media/filters/h264_parser.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace content {
+
+// Clients of this class are expected to pass H264 Annex-B byte stream
+// and are expected to provide an implementation of H264Accelerator for
+// offloading final steps of the decoding process.
+//
+// This class must be created, called and destroyed on a single thread, and
+// does nothing internally on any other thread.
+class CONTENT_EXPORT H264Decoder : public AcceleratedVideoDecoder {
+ public:
+  class CONTENT_EXPORT H264Accelerator {
+   public:
+    H264Accelerator() {}
+    virtual ~H264Accelerator() {}
+
+    virtual scoped_refptr<H264Picture> CreateH264Picture() = 0;
+
+    virtual bool SubmitFrameMetadata(const media::H264SPS* sps,
+                                     const media::H264PPS* pps,
+                                     const H264DPB& dpb,
+                                     const H264Picture::Vector& ref_pic_listp0,
+                                     const H264Picture::Vector& ref_pic_listb0,
+                                     const H264Picture::Vector& ref_pic_listb1,
+                                     const scoped_refptr<H264Picture>& pic) = 0;
+
+    virtual bool SubmitSlice(const media::H264PPS* pps,
+                             const media::H264SliceHeader* slice_hdr,
+                             const H264Picture::Vector& ref_pic_list0,
+                             const H264Picture::Vector& ref_pic_list1,
+                             const scoped_refptr<H264Picture>& pic,
+                             const uint8_t* data,
+                             size_t size) = 0;
+
+    virtual bool SubmitDecode(const scoped_refptr<H264Picture>& pic) = 0;

[Owen Lin, 2015/01/08 15:42:06]

Add docs. I cannot figure out how these function work, it seems not trivial.

[Pawel Osciak, 2015/01/12 07:18:19]

Done.

+    virtual bool OutputPicture(const scoped_refptr<H264Picture>& pic) = 0;
+
+    DISALLOW_COPY_AND_ASSIGN(H264Accelerator);

[Owen Lin, 2015/01/08 15:42:06]

put it under "private:"

[Pawel Osciak, 2015/01/12 07:18:19]

Done.

+  };
+
+  H264Decoder(H264Accelerator* accelerator);
+  virtual ~H264Decoder();
+
+  // content::AcceleratedVideoDecoder implementation.
+  bool Flush() override WARN_UNUSED_RESULT;
+  void Reset() override;
+  void SetStream(const uint8* ptr, size_t size) override;
+  DecResult Decode() override WARN_UNUSED_RESULT;
+  gfx::Size GetPicSize() override { return pic_size_; }
+  size_t GetRequiredNumOfPictures() override;
+
+ private:
+  // We need to keep at most kDPBMaxSize pictures in DPB for
+  // reference/to display later and an additional one for the one currently
+  // being decoded. We also ask for some additional ones since VDA needs
+  // to accumulate a few ready-to-output pictures before it actually starts
+  // displaying and giving them back. +2 instead of +1 because of subjective
+  // smoothness improvement during testing.
+  enum {
+    kPicsInPipeline = media::limits::kMaxVideoFrames + 2,
+    kMaxNumReqPictures = H264DPB::kDPBMaxSize + kPicsInPipeline,
+  };
+
+  // Internal state of the decoder.
+  enum State {
+    kNeedStreamMetadata,  // After initialization, need an SPS.
+    kDecoding,            // Ready to decode from any point.
+    kAfterReset,          // After Reset(), need a resume point.
+    kError,               // Error in decode, can't continue.
+  };
+
+  // Process H264 stream structures.
+  bool ProcessSPS(int sps_id, bool* need_new_buffers);
+  bool ProcessPPS(int pps_id);
+  bool PreprocessSlice(media::H264SliceHeader* slice_hdr);
+  bool ProcessSlice(media::H264SliceHeader* slice_hdr);
+
+  // Initialize the current picture according to data in |slice_hdr|.
+  bool InitCurrPicture(media::H264SliceHeader* slice_hdr);
+
+  // Calculate picture order counts for the new picture
+  // on initialization of a new frame (see spec).
+  bool CalculatePicOrderCounts(media::H264SliceHeader* slice_hdr);
+
+  // Update PicNum values in pictures stored in DPB on creation of new
+  // frame (see spec).
+  void UpdatePicNums();
+
+  bool UpdateMaxNumReorderFrames(const media::H264SPS* sps);
+
+  // Prepare reference picture lists for the current frame.
+  void PrepareRefPicLists(media::H264SliceHeader* slice_hdr);
+  // Prepare reference picture lists for the given slice.
+  bool ModifyReferencePicLists(media::H264SliceHeader* slice_hdr,
+                               H264Picture::Vector* ref_pic_list0,
+                               H264Picture::Vector* ref_pic_list1);
+
+  // Construct initial reference picture lists for use in decoding of
+  // P and B pictures (see 8.2.4 in spec).
+  void ConstructReferencePicListsP(media::H264SliceHeader* slice_hdr);
+  void ConstructReferencePicListsB(media::H264SliceHeader* slice_hdr);
+
+  // Helper functions for reference list construction, per spec.
+  int PicNumF(const scoped_refptr<H264Picture>& pic);
+  int LongTermPicNumF(const scoped_refptr<H264Picture>& pic);
+
+  // Perform the reference picture lists' modification (reordering), as
+  // specified in spec (8.2.4).
+  //
+  // |list| indicates list number and should be either 0 or 1.
+  bool ModifyReferencePicList(media::H264SliceHeader* slice_hdr,
+                              int list,
+                              H264Picture::Vector* ref_pic_listx);
+
+  // Perform reference picture memory management operations (marking/unmarking
+  // of reference pictures, long term picture management, discarding, etc.).
+  // See 8.2.5 in spec.
+  bool HandleMemoryManagementOps();
+  void ReferencePictureMarking();
+
+  // Start processing a new frame.
+  bool StartNewFrame(media::H264SliceHeader* slice_hdr);
+
+  // All data for a frame received, process it and decode.
+  bool FinishPrevFrameIfPresent();
+
+  // Called after decoding, performs all operations to be done after decoding,
+  // including DPB management, reference picture marking and memory management
+  // operations.
+  // This will also output a picture if one is ready for output.
+  bool FinishPicture();
+
+  // Clear DPB contents and remove all surfaces in DPB from *in_use_ list.
+  // Cleared pictures will be made available for decode, unless they are
+  // at client waiting to be displayed.
+  void ClearDPB();
+
+  // Commits all pending data for HW decoder and starts HW decoder.
+  bool DecodePicture();
+
+  // Notifies client that a picture is ready for output.
+  void OutputPic(scoped_refptr<H264Picture> pic);
+
+  // Output all pictures in DPB that have not been outputted yet.
+  bool OutputAllRemainingPics();
+
+  // Decoder state.
+  State state_;
+
+  // Parser in use.
+  media::H264Parser parser_;
+
+  // DPB in use.
+  H264DPB dpb_;
+
+  // Picture currently being processed/decoded.
+  scoped_refptr<H264Picture> curr_pic_;
+
+  // Reference picture lists, constructed for each frame.
+  H264Picture::Vector ref_pic_list_p0_;
+  H264Picture::Vector ref_pic_list_b0_;
+  H264Picture::Vector ref_pic_list_b1_;
+
+  // Global state values, needed in decoding. See spec.
+  int max_pic_order_cnt_lsb_;
+  int max_frame_num_;
+  int max_pic_num_;
+  int max_long_term_frame_idx_;
+  size_t max_num_reorder_frames_;
+
+  int frame_num_;
+  int prev_frame_num_;
+  int prev_frame_num_offset_;
+  bool prev_has_memmgmnt5_;
+
+  // Values related to previously decoded reference picture.
+  bool prev_ref_has_memmgmnt5_;
+  int prev_ref_top_field_order_cnt_;
+  int prev_ref_pic_order_cnt_msb_;
+  int prev_ref_pic_order_cnt_lsb_;
+  H264Picture::Field prev_ref_field_;
+
+  // Currently active SPS and PPS.
+  int curr_sps_id_;
+  int curr_pps_id_;
+
+  // Current NALU and slice header being processed.
+  scoped_ptr<media::H264NALU> curr_nalu_;
+  scoped_ptr<media::H264SliceHeader> curr_slice_hdr_;
+
+  // Output picture size.
+  gfx::Size pic_size_;
+
+  // PicOrderCount of the previously outputted frame.
+  int last_output_poc_;
+
+  H264Accelerator* accelerator_;
+
+  DISALLOW_COPY_AND_ASSIGN(H264Decoder);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_GPU_MEDIA_H264_DECODER_H_