1 /* Copyright (c) 2015 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 10 #ifndef WEBRTC_MODULES_VIDEO_CODING_CODECS_VP9_SCREENSHARE_LAYERS_H_ 11 #define WEBRTC_MODULES_VIDEO_CODING_CODECS_VP9_SCREENSHARE_LAYERS_H_ 12 13 #include "webrtc/modules/video_coding/codecs/vp9/vp9_impl.h" 14 15 namespace webrtc { 16 17 class ScreenshareLayersVP9 { 18 public: 19 explicit ScreenshareLayersVP9(uint8_t num_layers); 20 21 // The target bitrate for layer with id layer_id. 22 void ConfigureBitrate(int threshold_kbps, uint8_t layer_id); 23 24 // The current start layer. 25 uint8_t GetStartLayer() const; 26 27 // Update the layer with the size of the layer frame. 28 void LayerFrameEncoded(unsigned int size_bytes, uint8_t layer_id); 29 30 // Get the layer settings for the next superframe. 31 // 32 // In short, each time the GetSuperFrameSettings is called the 33 // bitrate of every layer is calculated and if the cummulative 34 // bitrate exceeds the configured cummulative bitrates 35 // (ConfigureBitrate to configure) up to and including that 36 // layer then the resulting encoding settings for the 37 // superframe will only encode layers above that layer. 38 VP9EncoderImpl::SuperFrameRefSettings GetSuperFrameSettings( 39 uint32_t timestamp, 40 bool is_keyframe); 41 42 private: 43 // How many layers that are used. 44 uint8_t num_layers_; 45 46 // The index of the first layer to encode. 47 uint8_t start_layer_; 48 49 // Cummulative target kbps for the different layers. 50 float threshold_kbps_[kMaxVp9NumberOfSpatialLayers - 1]; 51 52 // How many bits that has been used for a certain layer. Increased in 53 // FrameEncoded() by the size of the encoded frame and decreased in 54 // GetSuperFrameSettings() depending on the time between frames. 55 float bits_used_[kMaxVp9NumberOfSpatialLayers]; 56 57 // Timestamp of last frame. 58 uint32_t last_timestamp_; 59 60 // If the last_timestamp_ has been set. 61 bool timestamp_initialized_; 62 }; 63 64 } // namespace webrtc 65 66 #endif // WEBRTC_MODULES_VIDEO_CODING_CODECS_VP9_SCREENSHARE_LAYERS_H_ 67