| /* |
| * 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 COMMON_VIDEO_H264_SPS_PARSER_H_ |
| #define COMMON_VIDEO_H264_SPS_PARSER_H_ |
| |
| #include "absl/types/optional.h" |
| #include "rtc_base/bitstream_reader.h" |
| #include "rtc_base/system/rtc_export.h" |
| |
| namespace webrtc { |
| |
| // A class for parsing out sequence parameter set (SPS) data from an H264 NALU. |
| class RTC_EXPORT SpsParser { |
| public: |
| // The parsed state of the SPS. Only some select values are stored. |
| // Add more as they are actually needed. |
| struct RTC_EXPORT SpsState { |
| SpsState(); |
| SpsState(const SpsState&); |
| ~SpsState(); |
| |
| uint32_t width = 0; |
| uint32_t height = 0; |
| uint32_t delta_pic_order_always_zero_flag = 0; |
| uint32_t chroma_format_idc = 1; |
| uint32_t separate_colour_plane_flag = 0; |
| uint32_t frame_mbs_only_flag = 0; |
| uint32_t log2_max_frame_num = 4; // Smallest valid value. |
| uint32_t log2_max_pic_order_cnt_lsb = 4; // Smallest valid value. |
| uint32_t pic_order_cnt_type = 0; |
| uint32_t max_num_ref_frames = 0; |
| uint32_t vui_params_present = 0; |
| uint32_t id = 0; |
| }; |
| |
| // Unpack RBSP and parse SPS state from the supplied buffer. |
| static absl::optional<SpsState> ParseSps(rtc::ArrayView<const uint8_t> data); |
| // TODO: bugs.webrtc.org/42225170 - Deprecate. |
| static inline absl::optional<SpsState> ParseSps(const uint8_t* data, |
| size_t length) { |
| return ParseSps(rtc::MakeArrayView(data, length)); |
| } |
| |
| protected: |
| // Parse the SPS state, up till the VUI part, for a buffer where RBSP |
| // decoding has already been performed. |
| static absl::optional<SpsState> ParseSpsUpToVui(BitstreamReader& reader); |
| }; |
| |
| } // namespace webrtc |
| #endif // COMMON_VIDEO_H264_SPS_PARSER_H_ |