| // Copyright 2020 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 THIRD_PARTY_BLINK_RENDERER_MODULES_WEBCODECS_DECODER_SELECTOR_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_MODULES_WEBCODECS_DECODER_SELECTOR_H_ |
| |
| #include <memory> |
| |
| #include "base/memory/weak_ptr.h" |
| #include "media/base/demuxer_stream.h" |
| #include "media/base/media_util.h" |
| #include "media/filters/decoder_selector.h" |
| #include "media/filters/decoder_stream_traits.h" |
| #include "third_party/blink/renderer/modules/modules_export.h" |
| |
| namespace blink { |
| |
| template <media::DemuxerStream::Type StreamType> |
| class NullDemuxerStream; |
| |
| template <media::DemuxerStream::Type StreamType> |
| class DecoderSelector { |
| public: |
| typedef media::DecoderStreamTraits<StreamType> StreamTraits; |
| typedef typename StreamTraits::DecoderType Decoder; |
| typedef typename StreamTraits::DecoderConfigType DecoderConfig; |
| |
| // Callback to create a list of decoders to select from. |
| using CreateDecodersCB = |
| base::RepeatingCallback<std::vector<std::unique_ptr<Decoder>>()>; |
| |
| // Emits the result of a single call to SelectDecoder(). Parameter is |
| // the initialized Decoder. nullptr if selection failed. The caller owns the |
| // Decoder. |
| using SelectDecoderCB = base::OnceCallback<void(std::unique_ptr<Decoder>)>; |
| |
| // Construction can happen on any thread, but all subsequent API calls |
| // including destruction must use |task_runner| thread. |
| // Provided callbacks will be called on |task_runner|. |output_cb| will always |
| // be Post()'ed. |
| DecoderSelector(scoped_refptr<base::SequencedTaskRunner> task_runner, |
| CreateDecodersCB create_decoders_cb, |
| typename Decoder::OutputCB output_cb); |
| |
| // Aborts any pending decoder selection. |
| ~DecoderSelector(); |
| |
| // Disallow copy and assign. |
| DecoderSelector(const DecoderSelector&) = delete; |
| DecoderSelector& operator=(const DecoderSelector&) = delete; |
| |
| // Selects and initializes a decoder using |config|. Decoder will |
| // be returned via |select_decoder_cb| posted to |task_runner_|. Subsequent |
| // calls will again select from the full list of decoders. |
| void SelectDecoder(const DecoderConfig& config, |
| SelectDecoderCB select_decoder_cb); |
| |
| private: |
| // Helper to create |stream_traits_|. |
| std::unique_ptr<StreamTraits> CreateStreamTraits(); |
| |
| // Proxy SelectDecoderCB from impl_ to our |select_decoder_cb|. |
| void OnDecoderSelected(SelectDecoderCB select_decoder_cb, |
| std::unique_ptr<Decoder> decoder, |
| std::unique_ptr<media::DecryptingDemuxerStream>); |
| |
| // Implements heavy lifting for decoder selection. |
| media::DecoderSelector<StreamType> impl_; |
| |
| // Shim to satisfy dependencies of |impl_|. Provides DecoderConfig to |impl_|. |
| std::unique_ptr<NullDemuxerStream<StreamType>> demuxer_stream_; |
| |
| // Helper to unify API for configuring audio/video decoders. |
| std::unique_ptr<StreamTraits> stream_traits_; |
| |
| // Repeating callback for decoder outputs. |
| typename Decoder::OutputCB output_cb_; |
| |
| // TODO(chcunningham): Route MEDIA_LOG for WebCodecs. |
| media::NullMediaLog null_media_log_; |
| |
| base::WeakPtrFactory<DecoderSelector<StreamType>> weak_factory_{this}; |
| }; |
| |
| typedef DecoderSelector<media::DemuxerStream::VIDEO> |
| WebCodecsVideoDecoderSelector; |
| typedef DecoderSelector<media::DemuxerStream::AUDIO> |
| WebCodecsAudioDecoderSelector; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_MODULES_WEBCODECS_DECODER_SELECTOR_H_ |