diff --git a/zh-cn/application-dev/media/audio-capturer.md b/zh-cn/application-dev/media/audio-capturer.md new file mode 100644 index 0000000000000000000000000000000000000000..7d94aebb45a197eb1c05489f3fac14cafb799715 --- /dev/null +++ b/zh-cn/application-dev/media/audio-capturer.md @@ -0,0 +1,116 @@ +# AudioCapturer音频采集开发指南 + +# **场景介绍** + +AudioCapturer提供了用于获取原始音频文件的方法。开发者可以通过本指导了解应用如何通过AudioCapturer采集音频。 + +## 注意事项 + +在进行应用开发的过程中，建议开发者通过on('stateChange')方法订阅AudioCapturer的状态变更。因为针对AudioCapturer的某些操作，仅在音频采集器在固定状态时才能执行。如果应用在音频采集器处于错误状态时执行操作，系统可能会抛出异常或生成其他未定义的行为。 + +## 状态检查 + +应用程序开发人员应该记住，AudioCapturer 是基于状态的。
也就是说，AudioCapturer 有一个内部状态，应用程序在调用录制器控制 API 时必须始终检查该状态，因为某些操作仅在录制器处于给定状态时才可接受。 +如果应用程序在录制器处于不正确状态时执行操作，系统可能会抛出错误/异常或生成其他未定义的行为。 + +## 开发步骤 + +1. 使用createAudioCapturer()创建一个AudioCapturer实例。
在audioCapturerOptions中设置音频采集器的相关参数。该实例可用于音频采集、控制和获取采集状态，以及注册通知回调。 + + ``` + var audioStreamInfo = { + samplingRate: audio.AudioSamplingRate.SAMPLE_RATE_44100, + channels: audio.AudioChannel.CHANNEL_1, + sampleFormat: audio.AudioSampleFormat.SAMPLE_FORMAT_S16LE, + encodingType: audio.AudioEncodingType.ENCODING_TYPE_RAW + } + + var audioCapturerInfo = { + source: audio.SourceType.SOURCE_TYPE_MIC, + capturerFlags: 1 + } + + var audioCapturerOptions = { + streamInfo: audioStreamInfo, + capturerInfo: audioCapturerInfo + } + + let audioCapturer = await audio.createAudioCapturer(audioCapturerOptions); + var state = audioRenderer.state; + ``` + +2. 调用start()方法来启动/恢复采集任务。 + 启动完成后，采集器状态将变更为STATE_RUNNING，然后应用可以开始读取缓冲区。 + + ``` + await audioCapturer.start(); + if (audioCapturer.state == audio.AudioState.STATE_RUNNING) { + console.info('AudioRecLog: Capturer started'); + } else { + console.info('AudioRecLog: Capturer start failed'); + } + ``` + +3. 使用getBufferSize()方法获取要读取的最小缓冲区大小。 + + ``` + var bufferSize = await audioCapturer.getBufferSize(); + console.info('AudioRecLog: buffer size: ' + bufferSize); + ``` + +4. 读取采集器的音频数据并将其转换为字节流。重复调用read()方法读取数据，直到应用准备停止采集。 + 参考以下示例，将采集到的数据写入文件。 + + ``` + import fileio from '@ohos.fileio'; + + const path = '/data/data/.pulse_dir/capture_js.wav'; + let fd = fileio.openSync(path, 0o102, 0o777); + if (fd !== null) { + console.info('AudioRecLog: file fd created'); + } + else{ + console.info('AudioRecLog: file fd create : FAILED'); + return; + } + + fd = fileio.openSync(path, 0o2002, 0o666); + if (fd !== null) { + console.info('AudioRecLog: file fd opened in append mode'); + } + + var numBuffersToCapture = 150; + while (numBuffersToCapture) { + var buffer = await audioCapturer.read(bufferSize, true); + if (typeof(buffer) == undefined) { + console.info('read buffer failed'); + } else { + var number = fileio.writeSync(fd, buffer); + console.info('AudioRecLog: data written: ' + number); + } + + numBuffersToCapture--; + } + ``` + +5. 采集完成后，调用stop方法，停止录制。 + + ``` + await audioCapturer.stop(); + if (audioCapturer.state == audio.AudioState.STATE_STOPPED) { + console.info('AudioRecLog: Capturer stopped'); + } else { + console.info('AudioRecLog: Capturer stop failed'); + } + ``` + +6. 任务结束，调用release()方法释放相关资源。 + + ``` + await audioCapturer.release(); + if (audioCapturer.state == audio.AudioState.STATE_RELEASED) { + console.info('AudioRecLog: Capturer released'); + } else { + console.info('AudioRecLog: Capturer release failed'); + } + ``` \ No newline at end of file diff --git a/zh-cn/application-dev/media/audio-renderer.md b/zh-cn/application-dev/media/audio-renderer.md new file mode 100644 index 0000000000000000000000000000000000000000..d65ff2d6d9de496e1ba91e1162b66efb2aaacfc0 --- /dev/null +++ b/zh-cn/application-dev/media/audio-renderer.md @@ -0,0 +1,227 @@ +# AudioRenderer音频渲染开发指导 + +## 场景介绍 + +AudioRenderer提供了渲染音频文件和控制播放的接口，开发者可以通过本指导，了解如何在输出设备中播放音频文件并管理播放任务。
+同时，AudioRenderer支持音频中断的功能。
+**音频中断：** 当优先级较高的音频流需要播放时，AudioRenderer会中断优先级较低的流。例如，当用户在收听音乐时有来电，则优先级较低音乐播放将被暂停，具体可参考[开发步骤](#开发步骤）。 + +## 状态检查： + +您还应该记住，AudioRenderer 是基于状态的。 +也就是说，AudioRenderer 有一个内部状态，在调用播放控制 API 时必须始终检查它，因为某些操作仅在音频播放器处于给定状态时才可接受。 +如果您在不正确的状态下执行操作，系统可能会抛出错误/异常或生成其他未定义的行为。 + +## **异步操作：** + +大多数AudioRenderer调用都是异步的。因此，UI线程不会被阻塞。
对于每个API，框架都提供callback函数和promise函数。 +在本例中，为了简单起见，使用了promise函数。[**js api audio.md**](../reference/apis/js-apis-audio.md)为callback和promise提供参考。 + +## 使用步骤 + +1. 使用createAudioRenderer()创建一个AudioRenderer实例。 + 在audioCapturerOptions中设置相关参数。该实例可用于音频渲染、控制和获取采集状态，以及注册通知回调。 + + ``` + var audioStreamInfo = { + samplingRate: audio.AudioSamplingRate.SAMPLE_RATE_44100, + channels: audio.AudioChannel.CHANNEL_1, + sampleFormat: audio.AudioSampleFormat.SAMPLE_FORMAT_S16LE, + encodingType: audio.AudioEncodingType.ENCODING_TYPE_RAW + } + + var audioRendererInfo = { + content: audio.ContentType.CONTENT_TYPE_SPEECH, + usage: audio.StreamUsage.STREAM_USAGE_VOICE_COMMUNICATION, + rendererFlags: 1 + } + + var audioRendererOptions = { + streamInfo: audioStreamInfo, + rendererInfo: audioRendererInfo + } + + let audioRenderer = await audio.createAudioRenderer(audioRendererOptions); + ``` + +2. 使用on('interrupt')方法订阅音频中断事件。
当优先级更高或相等的Stream-B请求激活并使用输出设备时，Stream-A被中断。 + 在某些情况下，框架会采取暂停播放、降低音量等强制操作，并通过InterruptEvent通知应用。在其他情况下，应用可以自行对InterruptEvent做出响应。
+ 在音频中断的情况下，应用可能会碰到音频数据写入失败的问题。所以建议不感知、不处理中断的应用在写入音频数据前，使用audioRenderer.state检查播放器状态。而订阅音频中断事件，可以获取到更多详细信息，具体可参考[InterruptEvent](../reference/apis/js-apis-audio.md#interruptevent8)。 + +``` + audioRenderer.on('interrupt', (interruptEvent) => { + console.info('InterruptEvent Received'); + console.info('InterruptType: ' + interruptEvent.eventType); + console.info('InterruptForceType: ' + interruptEvent.forceType); + console.info('AInterruptHint: ' + interruptEvent.hintType); + + if (interruptEvent.forceType == audio.InterruptForceType.INTERRUPT_FORCE) { + switch (interruptEvent.hintType) { + // Force Pause: Action was taken by framework. + // Halt the write calls to avoid data loss. + case audio.InterruptHint.INTERRUPT_HINT_PAUSE: + isPlay = false; + break; + // Force Stop: Action was taken by framework. + // Halt the write calls to avoid data loss. + case audio.InterruptHint.INTERRUPT_HINT_STOP: + isPlay = false; + break; + // Force Duck: Action was taken by framework, + // just notifying the app that volume has been reduced. + case audio.InterruptHint.INTERRUPT_HINT_DUCK: + break; + // Force Unduck: Action was taken by framework, + // just notifying the app that volume has been restored. + case audio.InterruptHint.INTERRUPT_HINT_UNDUCK: + break; + } + } else if (interruptEvent.forceType == audio.InterruptForceType.INTERRUPT_SHARE) { + switch (interruptEvent.hintType) { + // Share Resume: Action is to be taken by App. + // Resume the force paused stream if required. + case audio.InterruptHint.INTERRUPT_HINT_RESUME: + startRenderer(); + break; + // Share Pause: Stream has been interrupted, + // It can choose to pause or play concurrently. + case audio.InterruptHint.INTERRUPT_HINT_PAUSE: + isPlay = false; + pauseRenderer(); + break; + } + } + }); + ``` + +3. 调用start()方法来启动/恢复播放任务。 + 启动完成后，渲染器状态将变更为STATE_RUNNING，然后应用可以开始读取缓冲区。 + + ``` + async function startRenderer() { + var state = audioRenderer.state; + // state should be prepared, paused or stopped. + if (state != audio.AudioState.STATE_PREPARED || state != audio.AudioState.STATE_PAUSED || + state != audio.AudioState.STATE_STOPPED) { + console.info('Renderer is not in a correct state to start'); + return; + } + + await audioRenderer.start(); + + state = audioRenderer.state; + if (state == audio.AudioState.STATE_RUNNING) { + console.info('Renderer started'); + } else { + console.error('Renderer start failed'); + } + } + ``` + +4. 调用write()方法向缓冲区写入数据。 + 将需要播放的音频数据读入缓冲区，重复调用write()方法写入。 + + ``` + async function writeBuffer(buf) { + var state = audioRenderer.state; + if (state != audio.AudioState.STATE_RUNNING) { + console.error('Renderer is not running, do not write'); + isPlay = false; + return; + } + let writtenbytes = await audioRenderer.write(buf); + + console.info('Actual written bytes: ' + writtenbytes); + if (writtenbytes < 0) { + console.error('Write buffer failed. check the state of renderer'); + } + } + + // Reasonable minimum buffer size for renderer. However, the renderer can accept other read sizes as well. + const bufferSize = await audioRenderer.getBufferSize(); + const path = '/data/file_example_WAV_2MG.wav'; + let ss = fileio.createStreamSync(path, 'r'); + const totalSize = 2146166; // file_example_WAV_2MG.wav + let rlen = 0; + let discardHeader = new ArrayBuffer(44); + ss.readSync(discardHeader); + rlen += 44; + + var id = setInterval(() => { + if (isPlay || isRelease) { + if (rlen >= totalSize || isRelease) { + ss.closeSync(); + stopRenderer(); + clearInterval(id); + } + let buf = new ArrayBuffer(bufferSize); + rlen += ss.readSync(buf); + console.info('Total bytes read from file: ' + rlen); + writeBuffer(buf); + } else { + console.info('check after next interval'); + } + } , 30); // interval to be set based on audio file format + ``` + +5. （可选）调用pause()方法或stop()方法暂停/停止渲染音频数据。 + + ``` + async function pauseRenderer() { + var state = audioRenderer.state; + if (state != audio.AudioState.STATE_RUNNING) { + console.info('Renderer is not running'); + return; + } + + await audioRenderer.pause(); + + state = audioRenderer.state; + if (state == audio.AudioState.STATE_PAUSED) { + console.info('Renderer paused'); + } else { + console.error('Renderer pause failed'); + } + } + + async function stopRenderer() { + var state = audioRenderer.state; + if (state != audio.AudioState.STATE_RUNNING || state != audio.AudioState.STATE_PAUSED) { + console.info('Renderer is not running or paused'); + return; + } + + await audioRenderer.stop(); + + state = audioRenderer.state; + if (state == audio.AudioState.STATE_STOPPED) { + console.info('Renderer stopped'); + } else { + console.error('Renderer stop failed'); + } + } + ``` + +6. 任务完成，调用release()方法释放相关资源。 + AudioRenderer会使用大量的系统资源，所以请确保完成相关任务后，进行资源释放。 + + ``` + async function releaseRenderer() { + if (state_ == RELEASED || state_ == NEW) { + console.info('Resourced already released'); + return; + } + + await audioRenderer.release(); + + state = audioRenderer.state; + if (state == STATE_RELEASED) { + console.info('Renderer released'); + } else { + console.info('Renderer release failed'); + } + + } + ``` + + \ No newline at end of file