AndroidUSBCamera基于[saki4510t/UVCCamera](https://github.com/saki4510t/UVCCamera)开发，该项目对USB Camera(UVC设备)的使用和视频数据采集进行了高度封装，能够帮助开发者通过几个简单的API实现USB Camera设备的检测、连接、预览和音视频数据采集，最重要的是手机无需root，只需支持otg功能即可驱动。主要功能包括：
(1)支持USB Camera设备检测，画面实时预览;
(2)支持本地录制mp4格式视频,支持实时获取音视频数据流;
(3)支持jpg格式图片抓拍;
(4)支持获取camera支持的分辨率，和分辨率切换;
(5)支持屏蔽声音,重启Camera;
(6)支持相机自动对焦；
(7)支持调整对比度和亮度
如何使用AndroidUSBCamera项目 
1. 添加依赖到本地工程
第一步 添加JitPack仓库到工程gradle
Step 1. Add the JitPack repository to your build file
Add it in your root build.gradle at the end of repositories:
allprojects {
repositories {
...
maven { url 'http://raw.github.com/saki4510t/libcommon/master/repository/' }
maven { url 'https://jitpack.io' }
}
}
第二步 添加依赖到app Module的gradle
Step 2. Add the dependency
dependencies {
compile 'com.github.jiangdongguo:AndroidUSBCamera:1.3.8'
}
2. 初始化引擎，注册USB设备事件监听器
Init AndroidUSBCamera engine，register the USB device event listener
private USBCameraManager.OnMyDevConnectListener listener = new USBCameraManager.OnMyDevConnectListener() {
// 插入USB设备
@Override
public void onAttachDev(UsbDevice device) {
if(mUSBManager == null || mUSBManager.getUsbDeviceCount() == 0){
showShortMsg("未检测到USB摄像头设备");
return;
}
// 请求打开摄像头
if(! isRequest){
isRequest = true;
if(mUSBManager != null){
mUSBManager.requestPermission(0);
}
}
}
// 拔出USB设备
@Override
public void onDettachDev(UsbDevice device) {
if(isRequest){
// 关闭摄像头
isRequest = false;
mUSBManager.closeCamera();
showShortMsg(device.getDeviceName()+"已拨出");
}
}
// 连接USB设备成功
@Override
public void onConnectDev(UsbDevice device,boolean isConnected) {
if(! isConnected) {
showShortMsg("连接失败，请检查分辨率参数是否正确");
isPreview = false;
}else{
isPreview = true;
}
}
// 与USB设备断开连接
@Override
public void onDisConnectDev(UsbDevice device) {
showShortMsg("连接失败");
}
};
mUVCCameraView = (CameraViewInterface) mTextureView;
mUVCCameraView.setCallback(new CameraViewInterface.Callback() {
@Override
public void onSurfaceCreated(CameraViewInterface view, Surface surface) {
if(!isPreview && mUSBManager.isCameraOpened()) {
mUSBManager.startPreview(mUVCCameraView, new AbstractUVCCameraHandler.OnPreViewResultListener() {
@Override
public void onPreviewResult(boolean result) {
}
});
isPreview = true;
}
}
@Override
public void onSurfaceChanged(CameraViewInterface view, Surface surface, int width, int height) {
}
@Override
public void onSurfaceDestroy(CameraViewInterface view, Surface surface) {
if(isPreview && mUSBManager.isCameraOpened()) {
mUSBManager.stopPreview();
isPreview = false;
}
}
});
// 初始化引擎
mUSBManager = USBCameraManager.getInstance();
mUSBManager.initUSBMonitor(this,listener);
mUSBManager.createUVCCamera(mUVCCameraView);
3. 注册USB设备广播事件监听器，开始Camera预览
Register the USB device broadcast event listener and start the Camera Preview
// 注册USB事件广播监听器
if(mUSBManager != null){
mUSBManager.registerUSB();
}
// 恢复Camera预览
if(mUVCCameraView != null){
mUVCCameraView.onResume();
}
4. 注销USB设备广播事件监听器，停止Camera预览
Unregister the USB device broadcast event listener and stop the Camera Preview
// 注销USB事件广播监听器
if(mUSBManager != null){
mUSBManager.unregisterUSB();
}
// 暂停Camera预览
if(mUVCCameraView != null){
mUVCCameraView.onPause();
}
5. 图片抓拍
Picture capturing
if(mUSBManager == null || ! mUSBManager.isCameraOpened()){
showShortMsg("抓拍异常，摄像头未开启");
return;
}
mUSBManager.capturePicture(picPath, new AbstractUVCCameraHandler.OnCaptureListener() {
@Override
public void onCaptureResult(String path) {
showShortMsg("保存路径："+path);
}
});
6. 本地录制(可实时获取音视频数据流)
recoring mp4，and get media real-stream
if(mUSBManager == null || ! mUSBManager.isCameraOpened()){
showShortMsg("录制异常，摄像头未开启");
return;
}
if(! mUSBManager.isRecording()){
String videoPath = USBCameraManager.ROOT_PATH+System.currentTimeMillis();
FileUtils.createfile(FileUtils.ROOT_PATH+"test666.h264");
RecordParams params = new RecordParams();
params.setRecordPath(videoPath);
params.setRecordDuration(0); // 设置为0，不分割保存
params.setVoiceClose(false); // 不屏蔽声音
mUSBManager.startRecording(params, new AbstractUVCCameraHandler.OnEncodeResultListener() {
@Override
public void onEncodeResult(byte[] data, int offset, int length, long timestamp, int type) {
// type = 0,aac格式音频流
// type = 1,h264格式视频流
if(type == 1){
FileUtils.putFileStream(data,offset,length);
}
}
@Override
public void onRecordResult(String videoPath) {
showShortMsg(videoPath);
}
});
// 停止录制
mUSBManager.stopRecording();
7. 切换分辨率
update Resulotion
mUSBManager.updateResolution(this, mUVCCameraView, 320, 240, new USBCameraManager.OnPreviewListener() {
@Override
public void onPreviewResult(boolean isSuccess) {
if(! isSuccess) {
showShortMsg("预览失败，不支持该分辨率");
}else {
showShortMsg("以切换到分辨率为320x240");
}
}
});
// 获取Camera支持得分辨率
List<Size> list = mUSBManager.getSupportedPreviewSizes();
// Camera自动对焦
mUSBManager.startCameraFoucs();
8. 释放引擎资源
release resource
// 释放资源9. 添加权限
if(mUSBManager != null){
mUSBManager.release();
}
add permissions
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
USBCameraManager API (Other)
(1) void requestPermission(int index)：请求授予开启USB摄像头权限；
(2) int getUsbDeviceCount()：返回查询到的可用USB Camera数目；
(3) boolean isRecording()：判断是否正在录制视频；
(4) boolean isCameraOpened()：判断USB摄像头是否正常打开；
(5) void release()：释放资源
(6) USBMonitor getUSBMonitor()：返回USBMonitor实例；
(7) mUSBManager.setModelValue(USBCameraManager.MODE_CONTRAST,contrast++); 调整对比度
(8) mUSBManager.setModelValue(USBCameraManager.MODE_BRIGHTNESS,brightness++);调整亮度
注：在使用Android Studio移植UVCCamera时，很多朋友可能会遇到"open（“/dev/bus/usb/001/002”, O_RDWR, 0），报错，Permission denied"问题，这是由于Android Studio使用的ndk版本所致，建议使用ndk-r14即可。解决方法：local.properties-->指定ndk.dir版本。(注：这里使用的是离线方式)
GitHub源码地址：https://github.com/jiangdongguo/AndroidUSBCamera(如果对您有用，欢迎star&fork以表支持~谢谢^_^！)