!3716 新增 opensles 录音说明资料

Merge pull request !3716 from liuyuehua/master

zh-cn/application-dev/media/Readme-CN.md

@@ -7,8 +7,9 @@
     - [音频渲染开发指导](audio-renderer.md)
     - [音频采集开发指导](audio-capturer.md)
     - [OpenSL ES播放开发指导](opensles-playback.md)
-- 视频
+    - [OpenSL ES录音开发指导](opensles-capture.md)
 
+- 视频
   - [视频播放开发指导](video-playback.md)
   - [视频录制开发指导](video-recorder.md)
 

zh-cn/application-dev/media/opensles-capture.md

+# OpenSL ES音频录制开发指导
+
+## 场景介绍
+
+开发者可以通过本文了解到在**OpenHarmony**如何使用**OpenSL ES**进行录音相关操作；当前仅实现了部分[**OpenSL ES**接口]  
+(https://gitee.com/openharmony/third_party_opensles/blob/master/api/1.0.1/OpenSLES.h)，未实现接口调用后会返回**SL_RESULT_FEATURE_UNSUPPORTED**
+
+ 
+
+## 开发步骤
+
+以下步骤描述了在**OpenHarmony**如何使用 **OpenSL ES** 开发音频录音功能：
+
+1. 添加头文件
+
+    ```c++
+    #include <OpenSLES.h>
+    #include <OpenSLES_OpenHarmony.h>
+    #include <OpenSLES_Platform.h>
+    ```
+
+2. 使用 **slCreateEngine** 接口创建引擎对象和实例化引擎对象 **engine**。
+
+    ```c++
+    SLObjectItf engineObject = nullptr;
+    slCreateEngine(&engineObject, 0, nullptr, 0, nullptr, nullptr);
+    (*engineObject)->Realize(engineObject, SL_BOOLEAN_FALSE);
+    ```
+
+    
+
+3. 获取接口 **SL_IID_ENGINE** 的引擎接口 **engineEngine** 实例
+
+    ```c++
+    SLEngineItf engineItf = nullptr;
+    result = (*engineObject)->GetInterface(engineObject, SL_IID_ENGINE, &engineItf);
+    ```
+
+    
+
+4. 配置录音器信息（配置输入源audiosource、输出源audiosink），创建录音对象**pcmCapturerObject** 。
+
+    ```c++
+    SLDataLocator_IODevice io_device = {
+        SL_DATALOCATOR_IODEVICE,
+        SL_IODEVICE_AUDIOINPUT,
+        SL_DEFAULTDEVICEID_AUDIOINPUT,
+        NULL
+    };
+
+    SLDataSource audioSource = {
+        &io_device,
+        NULL
+    };
+
+    SLDataLocator_BufferQueue buffer_queue = {
+        SL_DATALOCATOR_BUFFERQUEUE,
+        3
+    };
+
+    //具体参数需要根据音频文件格式进行适配
+    SLDataFormat_PCM format_pcm = {
+        SL_DATAFORMAT_PCM,
+        OHOS::AudioStandard::AudioChannel::MONO,
+        OHOS::AudioStandard::AudioSamplingRate::SAMPLE_RATE_44100,
+        OHOS::AudioStandard::AudioSampleFormat::SAMPLE_S16LE,
+        0,
+        0,
+        0
+    };
+
+    SLDataSink audioSink = {
+        &buffer_queue,
+        &format_pcm
+    };
+    
+    SLObjectItf pcmCapturerObject = nullptr;
+    result = (*engineItf)->CreateAudioRecorder(engineItf, &pcmCapturerObject,
+        &audioSource, &audioSink, 0, nullptr, nullptr);
+    (*pcmCapturerObject)->Realize(pcmCapturerObject, SL_BOOLEAN_FALSE);
+    ```
+
+5. 获取录音接口**SL_IID_RECORD** 的 **recordItf** 接口实例
+ 
+    ```
+    SLRecordItf  recordItf;
+    (*pcmCapturerObject)->GetInterface(pcmCapturerObject, SL_IID_RECORD, &recordItf);
+    ```   
+
+6. 获取接口 **SL_IID_OH_BUFFERQUEUE** 的 **bufferQueueItf** 实例
+
+    ```
+    SLOHBufferQueueItf bufferQueueItf;
+    (*pcmCapturerObject)->GetInterface(pcmCapturerObject, SL_IID_OH_BUFFERQUEUE, &bufferQueueItf);
+    ```
+
+    
+
+7. 注册 **BuqqerQueueCallback** 回调
+
+    ```c++
+    static void BufferQueueCallback(SLOHBufferQueueItf bufferQueueItf, void *pContext, SLuint32 size)
+    {
+        AUDIO_INFO_LOG("BufferQueueCallback");
+        FILE *wavFile = (FILE *)pContext;
+        if (wavFile != nullptr) {
+            SLuint8 *buffer = nullptr;
+            SLuint32 pSize = 0;
+            (*bufferQueueItf)->GetBuffer(bufferQueueItf, &buffer, pSize);
+            if (buffer != nullptr) {
+                fwrite(buffer, 1, pSize, wavFile);
+                (*bufferQueueItf)->Enqueue(bufferQueueItf, buffer, size);
+            } 
+        }
+
+        return;
+    }
+    
+    //wavFile_ 需要设置为用户想要录音的文件描述符
+    (*bufferQueueItf)->RegisterCallback(bufferQueueItf, BufferQueueCallback, wavFile_);
+    ```
+
+
+8. 开始录音
+
+    ```c++
+    static void CaptureStart(SLRecordItf recordItf, SLOHBufferQueueItf bufferQueueItf, FILE *wavFile)
+    {
+        AUDIO_INFO_LOG("CaptureStart");
+        (*recordItf)->SetRecordState(recordItf, SL_RECORDSTATE_RECORDING);
+        if (wavFile != nullptr) {
+            SLuint8* buffer = nullptr;
+            SLuint32 pSize = 0;
+            (*bufferQueueItf)->GetBuffer(bufferQueueItf, &buffer, pSize);
+            if (buffer != nullptr) {
+                AUDIO_INFO_LOG("CaptureStart, enqueue buffer length: %{public}lu.", pSize);
+                fwrite(buffer, 1, pSize, wavFile);
+                (*bufferQueueItf)->Enqueue(bufferQueueItf, buffer, pSize);
+            } else {
+                AUDIO_INFO_LOG("CaptureStart, buffer is null or pSize: %{public}lu.", pSize);
+            }
+        }
+
+        return;
+    }
+    ```
+
+
+9. 结束录音
+
+    ```c++
+    static void CaptureStop(SLRecordItf recordItf)
+    {
+        AUDIO_INFO_LOG("Enter CaptureStop");
+        fflush(wavFile_);
+        (*recordItf)->SetRecordState(recordItf, SL_RECORDSTATE_STOPPED);
+        (*pcmCapturerObject)->Destroy(pcmCapturerObject);
+        fclose(wavFile_);
+        wavFile_ = nullptr;
+        return;
+    }  
+    ```