1 /* 2 * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef MEDIA_BASE_SDP_VIDEO_FORMAT_UTILS_H_ 12 #define MEDIA_BASE_SDP_VIDEO_FORMAT_UTILS_H_ 13 14 #include "absl/types/optional.h" 15 #include "api/video_codecs/sdp_video_format.h" 16 17 namespace webrtc { 18 // Generate codec parameters that will be used as answer in an SDP negotiation 19 // based on local supported parameters and remote offered parameters. Both 20 // `local_supported_params`, `remote_offered_params`, and `answer_params` 21 // represent sendrecv media descriptions, i.e they are a mix of both encode and 22 // decode capabilities. In theory, when the profile in `local_supported_params` 23 // represent a strict superset of the profile in `remote_offered_params`, we 24 // could limit the profile in `answer_params` to the profile in 25 // `remote_offered_params`. However, to simplify the code, each supported H264 26 // profile should be listed explicitly in the list of local supported codecs, 27 // even if they are redundant. Then each local codec in the list should be 28 // tested one at a time against the remote codec, and only when the profiles are 29 // equal should this function be called. Therefore, this function does not need 30 // to handle profile intersection, and the profile of `local_supported_params` 31 // and `remote_offered_params` must be equal before calling this function. The 32 // parameters that are used when negotiating are the level part of 33 // profile-level-id and level-asymmetry-allowed. 34 void H264GenerateProfileLevelIdForAnswer( 35 const SdpVideoFormat::Parameters& local_supported_params, 36 const SdpVideoFormat::Parameters& remote_offered_params, 37 SdpVideoFormat::Parameters* answer_params); 38 39 // Parse max frame rate from SDP FMTP line. absl::nullopt is returned if the 40 // field is missing or not a number. 41 absl::optional<int> ParseSdpForVPxMaxFrameRate( 42 const SdpVideoFormat::Parameters& params); 43 44 // Parse max frame size from SDP FMTP line. absl::nullopt is returned if the 45 // field is missing or not a number. Please note that the value is stored in sub 46 // blocks but the returned value is in total number of pixels. 47 absl::optional<int> ParseSdpForVPxMaxFrameSize( 48 const SdpVideoFormat::Parameters& params); 49 50 } // namespace webrtc 51 52 #endif // MEDIA_BASE_SDP_VIDEO_FORMAT_UTILS_H_ 53