| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef MEDIA_FILTERS_FFMPEG_H264_TO_ANNEX_B_BITSTREAM_CONVERTER_H_ |
| #define MEDIA_FILTERS_FFMPEG_H264_TO_ANNEX_B_BITSTREAM_CONVERTER_H_ |
| |
| #include "base/basictypes.h" |
| #include "media/filters/h264_to_annex_b_bitstream_converter.h" |
| |
| // Forward declarations for FFmpeg datatypes used. |
| struct AVCodecContext; |
| struct AVPacket; |
| |
| namespace media { |
| |
| // Bitstream converter that converts H.264 bitstream based FFmpeg packets into |
| // H.264 Annex B bytestream format. |
| class MEDIA_EXPORT FFmpegH264ToAnnexBBitstreamConverter { |
| public: |
| // The |stream_context| will be used during conversion and should be the |
| // AVCodecContext for the stream sourcing these packets. A reference to |
| // |stream_context| is retained, so it must outlive this class. |
| explicit FFmpegH264ToAnnexBBitstreamConverter(AVCodecContext* stream_context); |
| ~FFmpegH264ToAnnexBBitstreamConverter(); |
| |
| // Converts |packet| to H.264 Annex B bytestream format. This conversion is |
| // on single NAL unit basis which is contained within the |packet| with the |
| // exception of the first packet which is prepended with the AVC decoder |
| // configuration record information. For example: |
| // |
| // NAL unit #1 ==> bytestream buffer #1 (AVC configuraion + NAL unit #1) |
| // NAL unit #2 ==> bytestream buffer #2 (NAL unit #2) |
| // ... |
| // NAL unit #n ==> bytestream buffer #n (NAL unit #n) |
| // |
| // Returns true if conversion succeeded. In this case, the output will be |
| // stored into the |packet|. But user should be aware that this conversion can |
| // free and reallocate the |packet|, if it needs to do so to fit it in. |
| // FFmpeg allocation methods will be used for buffer allocation to ensure |
| // compatibility with FFmpeg's memory management. |
| // |
| // Returns false if conversion failed. In this case, the |packet| will not |
| // be changed. |
| bool ConvertPacket(AVPacket* packet); |
| |
| private: |
| // Actual converter class. |
| H264ToAnnexBBitstreamConverter converter_; |
| |
| // Flag for indicating whether global parameter sets have been processed. |
| bool configuration_processed_; |
| |
| // Variable to hold a pointer to memory where we can access the global |
| // data from the FFmpeg file format's global headers. |
| AVCodecContext* stream_context_; |
| |
| DISALLOW_COPY_AND_ASSIGN(FFmpegH264ToAnnexBBitstreamConverter); |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_FILTERS_FFMPEG_H264_TO_ANNEX_B_BITSTREAM_CONVERTER_H_ |