1 /* Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
2 *
3 *  Use of this source code is governed by a BSD-style license
4 *  that can be found in the LICENSE file in the root of the source
5 *  tree. An additional intellectual property rights grant can be found
6 *  in the file PATENTS.  All contributing project authors may
7 *  be found in the AUTHORS file in the root of the source tree.
8 */
9 #ifndef WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_SCREENSHARE_LAYERS_H_
10 #define WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_SCREENSHARE_LAYERS_H_
11 
12 #include <list>
13 
14 #include "vpx/vpx_encoder.h"
15 
16 #include "webrtc/base/timeutils.h"
17 #include "webrtc/modules/video_coding/codecs/vp8/temporal_layers.h"
18 #include "webrtc/modules/video_coding/utility/frame_dropper.h"
19 #include "webrtc/typedefs.h"
20 
21 namespace webrtc {
22 
23 struct CodecSpecificInfoVP8;
24 
25 class ScreenshareLayers : public TemporalLayers {
26  public:
27   static const double kMaxTL0FpsReduction;
28   static const double kAcceptableTargetOvershoot;
29   static const int kTl0Flags;
30   static const int kTl1Flags;
31   static const int kTl1SyncFlags;
32 
33   ScreenshareLayers(int num_temporal_layers, uint8_t initial_tl0_pic_idx);
~ScreenshareLayers()34   virtual ~ScreenshareLayers() {}
35 
36   // Returns the recommended VP8 encode flags needed. May refresh the decoder
37   // and/or update the reference buffers.
38   int EncodeFlags(uint32_t timestamp) override;
39 
40   bool ConfigureBitrates(int bitrate_kbps,
41                          int max_bitrate_kbps,
42                          int framerate,
43                          vpx_codec_enc_cfg_t* cfg) override;
44 
45   void PopulateCodecSpecific(bool base_layer_sync,
46                              CodecSpecificInfoVP8* vp8_info,
47                              uint32_t timestamp) override;
48 
49   void FrameEncoded(unsigned int size, uint32_t timestamp, int qp) override;
50 
51   int CurrentLayerId() const override;
52 
53   // Allows the layers adapter to update the encoder configuration prior to a
54   // frame being encoded. Return true if the configuration should be updated
55   // and false if now change is needed.
56   bool UpdateConfiguration(vpx_codec_enc_cfg_t* cfg) override;
57 
58  private:
59   bool TimeToSync(int64_t timestamp) const;
60 
61   int number_of_temporal_layers_;
62   bool last_base_layer_sync_;
63   uint8_t tl0_pic_idx_;
64   int active_layer_;
65   int64_t last_timestamp_;
66   int64_t last_sync_timestamp_;
67   rtc::TimestampWrapAroundHandler time_wrap_handler_;
68   int min_qp_;
69   int max_qp_;
70   uint32_t max_debt_bytes_;
71   int frame_rate_;
72 
73   static const int kMaxNumTemporalLayers = 2;
74   struct TemporalLayer {
TemporalLayerTemporalLayer75     TemporalLayer()
76         : state(State::kNormal),
77           enhanced_max_qp(-1),
78           last_qp(-1),
79           debt_bytes_(0),
80           target_rate_kbps_(0) {}
81 
82     enum class State {
83       kNormal,
84       kDropped,
85       kReencoded,
86       kQualityBoost,
87     } state;
88 
89     int enhanced_max_qp;
90     int last_qp;
91     uint32_t debt_bytes_;
92     uint32_t target_rate_kbps_;
93 
94     void UpdateDebt(int64_t delta_ms);
95   } layers_[kMaxNumTemporalLayers];
96 };
97 }  // namespace webrtc
98 
99 #endif  // WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_SCREENSHARE_LAYERS_H_
100