| /* |
| * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #ifndef MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_ |
| #define MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_ |
| |
| #include <array> |
| #include <deque> |
| #include <map> |
| #include <memory> |
| #include <set> |
| #include <utility> |
| |
| #include "modules/include/module_common_types_public.h" |
| #include "modules/rtp_rtcp/source/rtp_video_header.h" |
| #include "modules/video_coding/codecs/vp9/include/vp9_globals.h" |
| #include "rtc_base/numerics/sequence_number_util.h" |
| #include "rtc_base/thread_annotations.h" |
| |
| namespace webrtc { |
| namespace video_coding { |
| |
| class EncodedFrame; |
| class RtpFrameObject; |
| |
| // A complete frame is a frame which has received all its packets and all its |
| // references are known. |
| class OnCompleteFrameCallback { |
| public: |
| virtual ~OnCompleteFrameCallback() {} |
| virtual void OnCompleteFrame(std::unique_ptr<EncodedFrame> frame) = 0; |
| }; |
| |
| class RtpFrameReferenceFinder { |
| public: |
| explicit RtpFrameReferenceFinder(OnCompleteFrameCallback* frame_callback); |
| explicit RtpFrameReferenceFinder(OnCompleteFrameCallback* frame_callback, |
| int64_t picture_id_offset); |
| ~RtpFrameReferenceFinder(); |
| |
| // Manage this frame until: |
| // - We have all information needed to determine its references, after |
| // which |frame_callback_| is called with the completed frame, or |
| // - We have too many stashed frames (determined by |kMaxStashedFrames|) |
| // so we drop this frame, or |
| // - It gets cleared by ClearTo, which also means we drop it. |
| void ManageFrame(std::unique_ptr<RtpFrameObject> frame); |
| |
| // Notifies that padding has been received, which the reference finder |
| // might need to calculate the references of a frame. |
| void PaddingReceived(uint16_t seq_num); |
| |
| // Clear all stashed frames that include packets older than |seq_num|. |
| void ClearTo(uint16_t seq_num); |
| |
| private: |
| static const uint16_t kPicIdLength = 1 << 15; |
| static const uint8_t kMaxTemporalLayers = 5; |
| static const int kMaxLayerInfo = 50; |
| static const int kMaxStashedFrames = 100; |
| static const int kMaxNotYetReceivedFrames = 100; |
| static const int kMaxGofSaved = 50; |
| static const int kMaxPaddingAge = 100; |
| |
| enum FrameDecision { kStash, kHandOff, kDrop }; |
| |
| struct GofInfo { |
| GofInfo(GofInfoVP9* gof, uint16_t last_picture_id) |
| : gof(gof), last_picture_id(last_picture_id) {} |
| GofInfoVP9* gof; |
| uint16_t last_picture_id; |
| }; |
| |
| // Find the relevant group of pictures and update its "last-picture-id-with |
| // padding" sequence number. |
| void UpdateLastPictureIdWithPadding(uint16_t seq_num); |
| |
| // Retry stashed frames until no more complete frames are found. |
| void RetryStashedFrames(); |
| |
| void HandOffFrame(std::unique_ptr<RtpFrameObject> frame); |
| |
| FrameDecision ManageFrameInternal(RtpFrameObject* frame); |
| |
| FrameDecision ManageFrameGeneric( |
| RtpFrameObject* frame, |
| const RTPVideoHeader::GenericDescriptorInfo& descriptor); |
| |
| // Find references for frames with no or very limited information in the |
| // descriptor. If |picture_id| is unspecified then packet sequence numbers |
| // will be used to determine the references of the frames. |
| FrameDecision ManageFramePidOrSeqNum(RtpFrameObject* frame, int picture_id); |
| |
| // Find references for Vp8 frames |
| FrameDecision ManageFrameVp8(RtpFrameObject* frame); |
| |
| // Updates necessary layer info state used to determine frame references for |
| // Vp8. |
| void UpdateLayerInfoVp8(RtpFrameObject* frame, |
| int64_t unwrapped_tl0, |
| uint8_t temporal_idx); |
| |
| // Find references for Vp9 frames |
| FrameDecision ManageFrameVp9(RtpFrameObject* frame); |
| |
| // Check if we are missing a frame necessary to determine the references |
| // for this frame. |
| bool MissingRequiredFrameVp9(uint16_t picture_id, const GofInfo& info); |
| |
| // Updates which frames that have been received. If there is a gap, |
| // missing frames will be added to |missing_frames_for_layer_| or |
| // if this is an already missing frame then it will be removed. |
| void FrameReceivedVp9(uint16_t picture_id, GofInfo* info); |
| |
| // Check if there is a frame with the up-switch flag set in the interval |
| // (|pid_ref|, |picture_id|) with temporal layer smaller than |temporal_idx|. |
| bool UpSwitchInIntervalVp9(uint16_t picture_id, |
| uint8_t temporal_idx, |
| uint16_t pid_ref); |
| |
| // Unwrap |frame|s picture id and its references to 16 bits. |
| void UnwrapPictureIds(RtpFrameObject* frame); |
| |
| // For every group of pictures, hold two sequence numbers. The first being |
| // the sequence number of the last packet of the last completed frame, and |
| // the second being the sequence number of the last packet of the last |
| // completed frame advanced by any potential continuous packets of padding. |
| std::map<uint16_t, |
| std::pair<uint16_t, uint16_t>, |
| DescendingSeqNumComp<uint16_t>> |
| last_seq_num_gop_; |
| |
| // Save the last picture id in order to detect when there is a gap in frames |
| // that have not yet been fully received. |
| int last_picture_id_; |
| |
| // Padding packets that have been received but that are not yet continuous |
| // with any group of pictures. |
| std::set<uint16_t, DescendingSeqNumComp<uint16_t>> stashed_padding_; |
| |
| // Frames earlier than the last received frame that have not yet been |
| // fully received. |
| std::set<uint16_t, DescendingSeqNumComp<uint16_t, kPicIdLength>> |
| not_yet_received_frames_; |
| |
| // Sequence numbers of frames earlier than the last received frame that |
| // have not yet been fully received. |
| std::set<uint16_t, DescendingSeqNumComp<uint16_t>> not_yet_received_seq_num_; |
| |
| // Frames that have been fully received but didn't have all the information |
| // needed to determine their references. |
| std::deque<std::unique_ptr<RtpFrameObject>> stashed_frames_; |
| |
| // Holds the information about the last completed frame for a given temporal |
| // layer given an unwrapped Tl0 picture index. |
| std::map<int64_t, std::array<int64_t, kMaxTemporalLayers>> layer_info_; |
| |
| // Where the current scalability structure is in the |
| // |scalability_structures_| array. |
| uint8_t current_ss_idx_; |
| |
| // Holds received scalability structures. |
| std::array<GofInfoVP9, kMaxGofSaved> scalability_structures_; |
| |
| // Holds the the Gof information for a given unwrapped TL0 picture index. |
| std::map<int64_t, GofInfo> gof_info_; |
| |
| // Keep track of which picture id and which temporal layer that had the |
| // up switch flag set. |
| std::map<uint16_t, uint8_t, DescendingSeqNumComp<uint16_t, kPicIdLength>> |
| up_switch_; |
| |
| // For every temporal layer, keep a set of which frames that are missing. |
| std::array<std::set<uint16_t, DescendingSeqNumComp<uint16_t, kPicIdLength>>, |
| kMaxTemporalLayers> |
| missing_frames_for_layer_; |
| |
| // How far frames have been cleared by sequence number. A frame will be |
| // cleared if it contains a packet with a sequence number older than |
| // |cleared_to_seq_num_|. |
| int cleared_to_seq_num_; |
| |
| OnCompleteFrameCallback* frame_callback_; |
| |
| // Unwrapper used to unwrap generic RTP streams. In a generic stream we derive |
| // a picture id from the packet sequence number. |
| SeqNumUnwrapper<uint16_t> rtp_seq_num_unwrapper_; |
| |
| // Unwrapper used to unwrap VP8/VP9 streams which have their picture id |
| // specified. |
| SeqNumUnwrapper<uint16_t, kPicIdLength> unwrapper_; |
| |
| SeqNumUnwrapper<uint8_t> tl0_unwrapper_; |
| |
| const int64_t picture_id_offset_; |
| }; |
| |
| } // namespace video_coding |
| } // namespace webrtc |
| |
| #endif // MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_ |