/* Copyright 2012 The Chromium Authors
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/**
* This file defines the <code>PPB_AudioInput_Dev</code> interface, which
* provides realtime audio input capture.
*/
label Chrome {
M25 = 0.3,
M30 = 0.4
};
/**
* <code>PPB_AudioInput_Callback</code> defines the type of an audio callback
* function used to provide the audio buffer with data. This callback will be
* called on a separate thread from the creation thread.
*
* @param[in] sample_buffer A buffer providing audio input data.
* @param[in] buffer_size_in_bytes The size of the buffer in bytes.
* @param[in] latency The time that has elapsed since the data was recorded.
* @param[inout] user_data An opaque pointer that was passed into
* <code>PPB_AudioInput_Dev.Open()</code>.
*/
typedef void PPB_AudioInput_Callback([in] mem_t sample_buffer,
[in] uint32_t buffer_size_in_bytes,
[in, version=0.4] PP_TimeDelta latency,
[inout] mem_t user_data);
/**
* The <code>PPB_AudioInput_Dev</code> interface contains pointers to several
* functions for handling audio input resources.
*
* TODO(brettw) before moving out of dev, we need to resolve the issue of
* the mismatch between the current audio config interface and this one.
*
* In particular, the params for input assume stereo, but this class takes
* everything as mono. We either need to not use an audio config resource, or
* add mono support.
*
* In addition, RecommendSampleFrameCount is completely wrong for audio input.
* RecommendSampleFrameCount returns the frame count for the current
* low-latency output device, which is likely inappropriate for a random input
* device. We may want to move the "recommend" functions to the input or output
* classes rather than the config.
*/
[macro="PPB_AUDIO_INPUT_DEV_INTERFACE"]
interface PPB_AudioInput_Dev {
/**
* Creates an audio input resource.
*
* @param[in] instance A <code>PP_Instance</code> identifying one instance of
* a module.
*
* @return A <code>PP_Resource</code> corresponding to an audio input resource
* if successful, 0 if failed.
*/
PP_Resource Create(
[in] PP_Instance instance);
/**
* Determines if the given resource is an audio input resource.
*
* @param[in] resource A <code>PP_Resource</code> containing a resource.
*
* @return A <code>PP_Bool</code> containing <code>PP_TRUE</code> if the given
* resource is an audio input resource, otherwise <code>PP_FALSE</code>.
*/
PP_Bool IsAudioInput(
[in] PP_Resource resource);
/**
* Enumerates audio input devices.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
* @param[in] output An output array which will receive
* <code>PPB_DeviceRef_Dev</code> resources on success. Please note that the
* ref count of those resources has already been increased by 1 for the
* caller.
* @param[in] callback A <code>PP_CompletionCallback</code> to run on
* completion.
*
* @return An error code from <code>pp_errors.h</code>.
*/
[version=0.3]
int32_t EnumerateDevices(
[in] PP_Resource audio_input,
[in] PP_ArrayOutput output,
[in] PP_CompletionCallback callback);
/**
* Requests device change notifications.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
* @param[in] callback The callback to receive notifications. If not NULL, it
* will be called once for the currently available devices, and then every
* time the list of available devices changes. All calls will happen on the
* same thread as the one on which MonitorDeviceChange() is called. It will
* receive notifications until <code>audio_input</code> is destroyed or
* <code>MonitorDeviceChange()</code> is called to set a new callback for
* <code>audio_input</code>. You can pass NULL to cancel sending
* notifications.
* @param[inout] user_data An opaque pointer that will be passed to
* <code>callback</code>.
*
* @return An error code from <code>pp_errors.h</code>.
*/
[version=0.3]
int32_t MonitorDeviceChange(
[in] PP_Resource audio_input,
[in] PP_MonitorDeviceChangeCallback callback,
[inout] mem_t user_data);
/**
* Opens an audio input device. No sound will be captured until
* StartCapture() is called.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
* @param[in] device_ref Identifies an audio input device. It could be one of
* the resource in the array returned by EnumerateDevices(), or 0 which means
* the default device.
* @param[in] config A <code>PPB_AudioConfig</code> audio configuration
* resource.
* @param[in] audio_input_callback A <code>PPB_AudioInput_Callback</code>
* function that will be called when data is available.
* @param[inout] user_data An opaque pointer that will be passed into
* <code>audio_input_callback</code>.
* @param[in] callback A <code>PP_CompletionCallback</code> to run when this
* open operation is completed.
*
* @return An error code from <code>pp_errors.h</code>.
*/
int32_t Open(
[in] PP_Resource audio_input,
[in] PP_Resource device_ref,
[in] PP_Resource config,
[in] PPB_AudioInput_Callback audio_input_callback,
[inout] mem_t user_data,
[in] PP_CompletionCallback callback);
/**
* Returns an audio config resource for the given audio input resource.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
*
* @return A <code>PP_Resource</code> containing the audio config resource if
* successful.
*/
PP_Resource GetCurrentConfig(
[in] PP_Resource audio_input);
/**
* Starts the capture of the audio input resource and begins periodically
* calling the callback.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
*
* @return A <code>PP_Bool</code> containing <code>PP_TRUE</code> if
* successful, otherwise <code>PP_FALSE</code>.
* Also returns <code>PP_TRUE</code> (and is a no-op) if called while capture
* is already started.
*/
PP_Bool StartCapture(
[in] PP_Resource audio_input);
/**
* Stops the capture of the audio input resource.
*
* @param[in] audio_input A PP_Resource containing the audio input resource.
*
* @return A <code>PP_Bool</code> containing <code>PP_TRUE</code> if
* successful, otherwise <code>PP_FALSE</code>.
* Also returns <code>PP_TRUE</code> (and is a no-op) if called while capture
* is already stopped. If a buffer is being captured, StopCapture will block
* until the call completes.
*/
PP_Bool StopCapture(
[in] PP_Resource audio_input);
/**
* Closes the audio input device, and stops capturing if necessary. It is
* not valid to call Open() again after a call to this method.
* If an audio input resource is destroyed while a device is still open, then
* it will be implicitly closed, so you are not required to call this method.
*
* @param[in] audio_input A <code>PP_Resource</code> corresponding to an audio
* input resource.
*/
void Close(
[in] PP_Resource audio_input);
};
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