我的Android进阶之旅------>Android视频录制小例子

2021-10-12 16:34:56

============================首先看看官网上关于视频捕捉的介绍================================

Capturing videos

Video capture using the Android framework requires careful management of the Camera object and coordination with the MediaRecorder class. When recording video with Camera, you must manage the Camera.lock() andCamera.unlock() calls to allow MediaRecorder access to the camera hardware, in addition to the Camera.open()and Camera.release() calls.

Note: Starting with Android 4.0 (API level 14), the Camera.lock() and Camera.unlock() calls are managed for you automatically.

Unlike taking pictures with a device camera, capturing video requires a very particular call order. You must follow a specific order of execution to successfully prepare for and capture video with your application, as detailed below.

Open Camera - Use the Camera.open() to get an instance of the camera object.
Connect Preview - Prepare a live camera image preview by connecting a SurfaceView to the camera usingCamera.setPreviewDisplay().
Start Preview - Call Camera.startPreview() to begin displaying the live camera images.
Start Recording Video - The following steps must be completed in order to successfully record video:
1. Unlock the Camera - Unlock the camera for use by MediaRecorder by calling Camera.unlock().
2. Configure MediaRecorder - Call in the following MediaRecorder methods in this order. For more information, see the MediaRecorder reference documentation.
  1. setCamera() - Set the camera to be used for video capture, use your application's current instance ofCamera.
  2. setAudioSource() - Set the audio source, use MediaRecorder.AudioSource.CAMCORDER.
  3. setVideoSource() - Set the video source, use MediaRecorder.VideoSource.CAMERA.
  4. Set the video output format and encoding. For Android 2.2 (API Level 8) and higher, use theMediaRecorder.setProfile method, and get a profile instance using CamcorderProfile.get(). For versions of Android prior to 2.2, you must set the video output format and encoding parameters:
    1. setOutputFormat() - Set the output format, specify the default setting orMediaRecorder.OutputFormat.MPEG_4.
    2. setAudioEncoder() - Set the sound encoding type, specify the default setting orMediaRecorder.AudioEncoder.AMR_NB.
    3. setVideoEncoder() - Set the video encoding type, specify the default setting orMediaRecorder.VideoEncoder.MPEG_4_SP.
  5. setOutputFile() - Set the output file, use getOutputMediaFile(MEDIA_TYPE_VIDEO).toString() from the example method in the Saving Media Files section.
  6. setPreviewDisplay() - Specify the SurfaceView preview layout element for your application. Use the same object you specified for Connect Preview.
  Caution: You must call these MediaRecorder configuration methods in this order, otherwise your application will encounter errors and the recording will fail.
3. Prepare MediaRecorder - Prepare the MediaRecorder with provided configuration settings by callingMediaRecorder.prepare().
4. Start MediaRecorder - Start recording video by calling MediaRecorder.start().
Stop Recording Video - Call the following methods in order, to successfully complete a video recording:
1. Stop MediaRecorder - Stop recording video by calling MediaRecorder.stop().
2. Reset MediaRecorder - Optionally, remove the configuration settings from the recorder by callingMediaRecorder.reset().
3. Release MediaRecorder - Release the MediaRecorder by calling MediaRecorder.release().
4. Lock the Camera - Lock the camera so that future MediaRecorder sessions can use it by callingCamera.lock(). Starting with Android 4.0 (API level 14), this call is not required unless theMediaRecorder.prepare() call fails.
Stop the Preview - When your activity has finished using the camera, stop the preview usingCamera.stopPreview().
Release Camera - Release the camera so that other applications can use it by calling Camera.release().

Note: It is possible to use MediaRecorder without creating a camera preview first and skip the first few steps of this process. However, since users typically prefer to see a preview before starting a recording, that process is not discussed here.

Tip: If your application is typically used for recording video, set setRecordingHint(boolean) to true prior to starting your preview. This setting can help reduce the time it takes to start recording.

============================再看看官网上关于音频捕捉的介绍================================

Audio Capture

The Android multimedia framework includes support for capturing and encoding a variety of common audio formats, so that you can easily integrate audio into your applications. You can record audio using the MediaRecorder APIs if supported by the device hardware.

This document shows you how to write an application that captures audio from a device microphone, save the audio and play it back.

Note: The Android Emulator does not have the ability to capture audio, but actual devices are likely to provide these capabilities.

Performing Audio Capture

Audio capture from the device is a bit more complicated than audio and video playback, but still fairly simple:

Create a new instance of android.media.MediaRecorder.
Set the audio source using MediaRecorder.setAudioSource(). You will probably want to useMediaRecorder.AudioSource.MIC.
Set output file format using MediaRecorder.setOutputFormat().
Set output file name using MediaRecorder.setOutputFile().
Set the audio encoder using MediaRecorder.setAudioEncoder().
Call MediaRecorder.prepare() on the MediaRecorder instance.
To start audio capture, call MediaRecorder.start().
To stop audio capture, call MediaRecorder.stop().
When you are done with the MediaRecorder instance, call MediaRecorder.release() on it. CallingMediaRecorder.release() is always recommended to free the resource immediately.

下面就看看该小例子的代码吧。

文件1.该应用的布局文件，res/layout/main.xml

<!-- 帧布局 -->
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="fill_parent" android:layout_height="fill_parent">
	
	<!-- 用来展示画面 -->
	<SurfaceView android:id="@+id/surfaceView"
		android:layout_width="fill_parent" android:layout_height="fill_parent" />
	
	<!-- 相对布局,该界面默认不显示出来，当触摸屏幕时候显示出来 -->
	<RelativeLayout android:layout_width="fill_parent"
		android:layout_height="fill_parent" android:visibility="gone"
		android:id="@+id/buttonlayout">
		<!-- 刻录按钮 -->
		<Button android:layout_width="wrap_content"
			android:layout_height="wrap_content" android:layout_alignParentRight="true"
			android:layout_alignParentBottom="true" android:layout_marginRight="10dp"
			android:text="@string/recoderbutton" android:onClick="recoder"
			android:id="@+id/recoderbutton" />
		<!-- 停止按钮 -->
		<Button android:layout_width="wrap_content"
			android:layout_height="wrap_content" android:layout_toLeftOf="@id/recoderbutton"
			android:layout_alignTop="@id/recoderbutton" android:layout_marginRight="30dp"
			android:text="@string/stopbutton" android:onClick="stop"
			android:id="@+id/stopbutton" 
			android:enabled="false"/>
	</RelativeLayout>
</FrameLayout>

文件2:布局文件所用到的资源文件，res/values/string.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, RecoderActivity!</string>
    <string name="app_name">视频刻录小例子</string>
    <string name="recoderbutton">刻录</string>
    <string name="stopbutton">停止</string>
    <string name="noSDcard">检测到手机没有存储卡！请插入手机存储卡再开启本应用</string>
    <string name="maxDuration">已经达到最长录制时间</string>
</resources>

文件3:该应用的主程序，RecoderActivity.java

package cn.oyp.recoder;

import java.io.File;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.media.MediaRecorder;
import android.media.MediaRecorder.OnInfoListener;
import android.os.Bundle;
import android.os.Environment;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.Toast;

public class RecoderActivity extends Activity {
	// 用来显示图片
	private SurfaceView surfaceView;
	// 刻录和停止按钮布局
	private RelativeLayout buttonlayout;
	// 刻录按钮
	private Button recoderbutton;
	// 停止按钮
	private Button stopbutton;
	// 媒体刻录对象
	private MediaRecorder mediaRecorder;

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		// 窗口特效为无标题
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		// 设置窗口全屏
		getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
				WindowManager.LayoutParams.FLAG_FULLSCREEN);
		// 设定屏幕显示为横向
		setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
		setContentView(R.layout.main);

		buttonlayout = (RelativeLayout) this.findViewById(R.id.buttonlayout);
		recoderbutton = (Button) this.findViewById(R.id.recoderbutton);
		stopbutton = (Button) this.findViewById(R.id.stopbutton);

		surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView);
		// 获取的画面直接输出到屏幕上
		surfaceView.getHolder()
				.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
		// 画面分辨率
		surfaceView.getHolder().setFixedSize(176, 144);
		// 保持屏幕高亮
		surfaceView.getHolder().setKeepScreenOn(true);
	}

	// 点击刻录按钮处理方法
	public void recoder(View v) {
		try {
			// 判断是否存在SD卡
			if (Environment.getExternalStorageState().equals(
					Environment.MEDIA_MOUNTED)) {
				// 将刻录的视频保存到SD卡中
				File videoFile = new File(
						Environment.getExternalStorageDirectory(),
						System.currentTimeMillis() + ".3gp");
				mediaRecorder = new MediaRecorder();
				// 设置声音采集来源于麦克风
				mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
				// 设置视频采集来源于摄像头
				mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
				// 设置输出格式为3gp
				mediaRecorder
						.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
				// 设置视频尺寸
				mediaRecorder.setVideoSize(surfaceView.getWidth(),
						surfaceView.getHeight());
				// 设置每秒钟捕捉画面个数为5帧
				mediaRecorder.setVideoFrameRate(5);
				// 设置声音编码
				mediaRecorder
						.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
				// 设置视频编码
				mediaRecorder.setAudioEncoder(MediaRecorder.VideoEncoder.H264);
				// 设置视频的最大持续时间
				mediaRecorder.setMaxDuration(10000);
				mediaRecorder.setOnInfoListener(new OnInfoListener() {
					@Override
					public void onInfo(MediaRecorder mr, int what, int extra) {
						if (what == MediaRecorder.MEDIA_RECORDER_INFO_MAX_DURATION_REACHED) {
							Toast.makeText(getApplicationContext(),
									R.string.maxDuration, Toast.LENGTH_LONG)
									.show();
							if (mediaRecorder != null) {
								mediaRecorder.stop();
								mediaRecorder.release();
								mediaRecorder = null;
							}
						}
					}
				});
				// 设置刻录的视频保存路径
				mediaRecorder.setOutputFile(videoFile.getAbsolutePath());
				// 设置预览显示
				mediaRecorder.setPreviewDisplay(surfaceView.getHolder()
						.getSurface());
				// 预期准备
				mediaRecorder.prepare();
				// 开始刻录
				mediaRecorder.start();
			} else {
				Toast.makeText(getApplicationContext(), R.string.noSDcard,
						Toast.LENGTH_LONG).show();
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		// 刻录按钮不可点击
		recoderbutton.setEnabled(false);
		// 停止按钮可点击
		stopbutton.setEnabled(true);
	}

	// 点击停止按钮处理方法
	public void stop(View v) {
		// 停止刻录,并释放资源
		if (mediaRecorder != null) {
			mediaRecorder.stop();
			mediaRecorder.release();
			mediaRecorder = null;
		}
		// 刻录按钮可点击
		recoderbutton.setEnabled(true);
		// 停止按钮不可点击
		stopbutton.setEnabled(false);
	}

	/** 当触摸屏幕的时候，将对焦和拍照按钮布局显示出来 */
	@Override
	public boolean onTouchEvent(MotionEvent event) {
		if (event.getAction() == MotionEvent.ACTION_DOWN) {
			buttonlayout.setVisibility(ViewGroup.VISIBLE);
			return true;
		}
		return super.onTouchEvent(event);
	}

}

文件4:该应用的描述文件，AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
	package="cn.oyp.recoder" android:versionCode="1" android:versionName="1.0">
	<uses-sdk android:minSdkVersion="8" />

	<!-- 摄像头权限 -->
	<uses-permission android:name="android.permission.CAMERA" />
	<!-- 录制音频权限 -->
	<uses-permission android:name="android.permission.RECORD_AUDIO"/>
	<!-- 在SD卡中创建和删除文件权限 -->
	<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
	<!-- 往SD卡中写入数据的权限 -->
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
	

	<application android:icon="@drawable/icon" android:label="@string/app_name">
		<activity android:name=".RecoderActivity" android:label="@string/app_name"
			android:screenOrientation="landscape">
			<intent-filter>
				<action android:name="android.intent.action.MAIN" />
				<category android:name="android.intent.category.LAUNCHER" />
			</intent-filter>
		</activity>

	</application>
</manifest>

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作者：欧阳鹏欢迎转载，与人分享是进步的源泉！

转载请保留原文地址：http://blog.csdn.net/ouyang_peng

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码农公寓

Capturing videos

Audio Capture

Performing Audio Capture

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