1 /* 2 * Copyright (c) 2021 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 API_VIDEO_CODECS_H264_PROFILE_LEVEL_ID_H_ 12 #define API_VIDEO_CODECS_H264_PROFILE_LEVEL_ID_H_ 13 14 #include <string> 15 16 #include "absl/types/optional.h" 17 #include "api/video_codecs/sdp_video_format.h" 18 #include "rtc_base/system/rtc_export.h" 19 20 namespace webrtc { 21 22 enum class H264Profile { 23 kProfileConstrainedBaseline, 24 kProfileBaseline, 25 kProfileMain, 26 kProfileConstrainedHigh, 27 kProfileHigh, 28 kProfilePredictiveHigh444, 29 }; 30 31 // All values are equal to ten times the level number, except level 1b which is 32 // special. 33 enum class H264Level { 34 kLevel1_b = 0, 35 kLevel1 = 10, 36 kLevel1_1 = 11, 37 kLevel1_2 = 12, 38 kLevel1_3 = 13, 39 kLevel2 = 20, 40 kLevel2_1 = 21, 41 kLevel2_2 = 22, 42 kLevel3 = 30, 43 kLevel3_1 = 31, 44 kLevel3_2 = 32, 45 kLevel4 = 40, 46 kLevel4_1 = 41, 47 kLevel4_2 = 42, 48 kLevel5 = 50, 49 kLevel5_1 = 51, 50 kLevel5_2 = 52 51 }; 52 53 struct H264ProfileLevelId { H264ProfileLevelIdH264ProfileLevelId54 constexpr H264ProfileLevelId(H264Profile profile, H264Level level) 55 : profile(profile), level(level) {} 56 H264Profile profile; 57 H264Level level; 58 }; 59 60 // Parse profile level id that is represented as a string of 3 hex bytes. 61 // Nothing will be returned if the string is not a recognized H264 62 // profile level id. 63 absl::optional<H264ProfileLevelId> ParseH264ProfileLevelId(const char* str); 64 65 // Parse profile level id that is represented as a string of 3 hex bytes 66 // contained in an SDP key-value map. A default profile level id will be 67 // returned if the profile-level-id key is missing. Nothing will be returned if 68 // the key is present but the string is invalid. 69 RTC_EXPORT absl::optional<H264ProfileLevelId> ParseSdpForH264ProfileLevelId( 70 const SdpVideoFormat::Parameters& params); 71 72 // Given that a decoder supports up to a given frame size (in pixels) at up to a 73 // given number of frames per second, return the highest H.264 level where it 74 // can guarantee that it will be able to support all valid encoded streams that 75 // are within that level. 76 RTC_EXPORT absl::optional<H264Level> H264SupportedLevel( 77 int max_frame_pixel_count, 78 float max_fps); 79 80 // Returns canonical string representation as three hex bytes of the profile 81 // level id, or returns nothing for invalid profile level ids. 82 RTC_EXPORT absl::optional<std::string> H264ProfileLevelIdToString( 83 const H264ProfileLevelId& profile_level_id); 84 85 // Returns true if the parameters have the same H264 profile (Baseline, High, 86 // etc). 87 RTC_EXPORT bool H264IsSameProfile(const SdpVideoFormat::Parameters& params1, 88 const SdpVideoFormat::Parameters& params2); 89 90 } // namespace webrtc 91 92 #endif // API_VIDEO_CODECS_H264_PROFILE_LEVEL_ID_H_ 93