| // Copyright 2015 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 PPAPI_CPP_AUDIO_ENCODER_H_ |
| #define PPAPI_CPP_AUDIO_ENCODER_H_ |
| |
| #include <stdint.h> |
| |
| #include "ppapi/c/pp_codecs.h" |
| #include "ppapi/c/ppb_audio_buffer.h" |
| #include "ppapi/cpp/audio_buffer.h" |
| #include "ppapi/cpp/completion_callback.h" |
| #include "ppapi/cpp/resource.h" |
| |
| /// @file |
| /// This file defines the API to create and use a AudioEncoder resource. |
| |
| namespace pp { |
| |
| class InstanceHandle; |
| |
| /// Audio encoder interface. |
| /// |
| /// Typical usage: |
| /// - Call Create() to create a new audio encoder resource. |
| /// - Call GetSupportedFormats() to determine which codecs and profiles are |
| /// available. |
| /// - Call Initialize() to initialize the encoder for a supported profile. |
| /// - Call GetBuffer() to get a blank frame and fill it in, or get an audio |
| /// frame from another resource, e.g. <code>PPB_MediaStreamAudioTrack</code>. |
| /// - Call Encode() to push the audio buffer to the encoder. If an external |
| /// buffer is pushed, wait for completion to recycle the frame. |
| /// - Call GetBitstreamBuffer() continuously (waiting for each previous call to |
| /// complete) to pull encoded buffers from the encoder. |
| /// - Call RecycleBitstreamBuffer() after consuming the data in the bitstream |
| /// buffer. |
| /// - To destroy the encoder, the plugin should release all of its references to |
| /// it. Any pending callbacks will abort before the encoder is destroyed. |
| /// |
| /// Available audio codecs vary by platform. |
| /// All: opus. |
| class AudioEncoder : public Resource { |
| public: |
| /// Default constructor for creating an is_null() <code>AudioEncoder</code> |
| /// object. |
| AudioEncoder(); |
| |
| /// A constructor used to create a <code>AudioEncoder</code> and associate it |
| /// with the provided <code>Instance</code>. |
| /// @param[in] instance The instance with which this resource will be |
| /// associated. |
| explicit AudioEncoder(const InstanceHandle& instance); |
| |
| /// The copy constructor for <code>AudioEncoder</code>. |
| /// @param[in] other A reference to a <code>AudioEncoder</code>. |
| AudioEncoder(const AudioEncoder& other); |
| |
| /// Gets an array of supported audio encoder profiles. |
| /// These can be used to choose a profile before calling Initialize(). |
| /// |
| /// @param[in] callback A <code>CompletionCallbackWithOutput</code> to be |
| /// called upon completion with the PP_AudioProfileDescription structs. |
| /// |
| /// @return If >= 0, the number of supported profiles returned, otherwise an |
| /// error code from <code>pp_errors.h</code>. |
| int32_t GetSupportedProfiles(const CompletionCallbackWithOutput< |
| std::vector<PP_AudioProfileDescription> >& cc); |
| |
| /// Initializes a audio encoder resource. This should be called after |
| /// GetSupportedProfiles() and before any functions below. |
| /// |
| /// @param[in] channels The number of audio channels to encode. |
| /// @param[in] input_sampling_rate The sampling rate of the input audio |
| /// buffer. |
| /// @param[in] input_sample_size The sample size of the input audio buffer. |
| /// @param[in] output_profile A <code>PP_AudioProfile</code> specifying the |
| /// codec profile of the encoded output stream. |
| /// @param[in] initial_bitrate The initial bitrate for the encoder. |
| /// @param[in] acceleration A <code>PP_HardwareAcceleration</code> specifying |
| /// whether to use a hardware accelerated or a software implementation. |
| /// @param[in] callback A <code>CompletionCallback</code> to be called upon |
| /// completion. |
| /// |
| /// @return An int32_t containing an error code from <code>pp_errors.h</code>. |
| /// Returns PP_ERROR_NOTSUPPORTED if audio encoding is not available, or the |
| /// requested codec profile is not supported. |
| /// Returns PP_ERROR_NOMEMORY if bitstream buffers can't be created. |
| int32_t Initialize(uint32_t channels, |
| PP_AudioBuffer_SampleRate input_sample_rate, |
| PP_AudioBuffer_SampleSize input_sample_size, |
| PP_AudioProfile output_profile, |
| uint32_t initial_bitrate, |
| PP_HardwareAcceleration acceleration, |
| const CompletionCallback& cc); |
| |
| /// Gets the number of audio samples per channel that audio buffers |
| /// must contain in order to be processed by the encoder. This will |
| /// be the number of samples per channels contained in buffers |
| /// returned by GetBuffer(). |
| /// |
| /// @return An int32_t containing the number of samples required, or an error |
| /// code from <code>pp_errors.h</code>. |
| /// Returns PP_ERROR_FAILED if Initialize() has not successfully completed. |
| int32_t GetNumberOfSamples(); |
| |
| /// Gets a blank audio frame which can be filled with audio data and passed |
| /// to the encoder. |
| /// |
| /// @param[in] callback A <code>CompletionCallbackWithOutput</code> to be |
| /// called upon completion with the blank <code>AudioBuffer</code> resource. |
| /// |
| /// @return An int32_t containing an error code from <code>pp_errors.h</code>. |
| int32_t GetBuffer(const CompletionCallbackWithOutput<AudioBuffer>& cc); |
| |
| /// Encodes an audio buffer. |
| /// |
| /// @param[in] audio_buffer The <code>AudioBuffer</code> to be encoded. |
| /// @param[in] callback A <code>CompletionCallback</code> to be called upon |
| /// completion. Plugins that pass <code>AudioBuffer</code> resources owned |
| /// by other resources should wait for completion before reusing them. |
| /// |
| /// @return An int32_t containing an error code from <code>pp_errors.h</code>. |
| /// Returns PP_ERROR_FAILED if Initialize() has not successfully completed. |
| int32_t Encode(const AudioBuffer& buffer, const CompletionCallback& cc); |
| |
| /// Gets the next encoded bitstream buffer from the encoder. |
| /// |
| /// @param[in] callback A <code>CompletionCallbackWithOutput</code> to be |
| /// called upon completion with the next bitstream buffer. The plugin can call |
| /// GetBitstreamBuffer from the callback in order to continuously "pull" |
| /// bitstream buffers from the encoder. |
| /// |
| /// @return An int32_t containing an error code from <code>pp_errors.h</code>. |
| /// Returns PP_ERROR_FAILED if Initialize() has not successfully completed. |
| /// Returns PP_ERROR_INPROGRESS if a prior call to GetBitstreamBuffer() has |
| /// not completed. |
| int32_t GetBitstreamBuffer( |
| const CompletionCallbackWithOutput<PP_AudioBitstreamBuffer>& cc); |
| |
| /// Recycles a bitstream buffer back to the encoder. |
| /// |
| /// @param[in] bitstream_buffer A<code>PP_AudioBitstreamBuffer</code> that |
| /// is no longer needed by the plugin. |
| void RecycleBitstreamBuffer(const PP_AudioBitstreamBuffer& bitstream_buffer); |
| |
| /// Requests a change to the encoding bitrate. This is only a request, |
| /// fulfilled on a best-effort basis. |
| /// |
| /// @param[in] audio_encoder A <code>PP_Resource</code> identifying the audio |
| /// encoder. |
| void RequestBitrateChange(uint32_t bitrate); |
| |
| /// Closes the audio encoder, and cancels any pending encodes. Any pending |
| /// callbacks will still run, reporting <code>PP_ERROR_ABORTED</code> . It is |
| /// not valid to call any encoder functions after a call to this method. |
| /// <strong>Note:</strong> Destroying the audio encoder closes it implicitly, |
| /// so you are not required to call Close(). |
| void Close(); |
| }; |
| |
| } // namespace pp |
| |
| #endif // PPAPI_CPP_AUDIO_ENCODER_H_ |