Android开启相机预览获取Yuv视频流数据

自定义surfaceview

主要步骤：

实现surfaceholder.callback接口，创建surfaceview的生命周期

实现camera.previewcallback接口，创建预览回调接口

创建camera打开相机

实例：

public class camerasurfaceviews extends surfaceview implements surfaceholder.callback, camera.previewcallback{

    context mcontext;
    surfaceholder msurfaceholder;//surface的控制器
    camera mcamera;//相机类
    framecallback mcb;//数据回调接口

    public void setmcb(framecallback mcb) {
        this.mcb = mcb;
    }

　　 //获取surfaceview的surfaceholder对象和接口
    public camerasurfaceviews(context context, attributeset attrs) {
        super(context, attrs);
        mcontext = context;
        msurfaceholder = getholder();
        msurfaceholder.addcallback(this);

    }

    //寻找相机
    private int findcamera(boolean isfront) {
        int cameracount = 0;
        camera.camerainfo camerainfo = new camera.camerainfo();
        cameracount = camera.getnumberofcameras();

        for (int camidx = 0; camidx < cameracount; camidx++) {
            camera.getcamerainfo(camidx, camerainfo);
            if (isfront) {
                // camera_facing_front前置
                if (camerainfo.facing == camera.camerainfo.camera_facing_front) {
                    return camidx;
                }
            } else {
                // camera_facing_back后置
                if (camerainfo.facing == camera.camerainfo.camera_facing_back) {
                    return camidx;
                }
            }

        }
        return -1;
    }

    //打开相机
    private camera getcamera() {
        camera camera = null;
        int cameraid = findcamera(false);
        try {
            if(cameraid==1){
               camera = camera.open(cameraid );
            }else if(cameraid==0)(
                camera = camera.open(0);
            }
　　　　　　　   
        } catch (exception e) {
            camera = null;
        }
        return camera;
    }

    //surface被创建时调用
    @override
    public void surfacecreated(surfaceholder holder) {
        mcamera = getcamera();
　　　　 
    }

    //surface大小被改变时调用
    @override
    public void surfacechanged(surfaceholder holder, int format, int width,int height) {
　　　　setstartpreview(mcamera,msurfaceholder);
    }

　　//surface被销毁时调用
    @override
    public void surfacedestroyed(surfaceholder holder) {
        releasecamera();
    }

    //开启相机预览
    private void setstartpreview(camera camera, surfaceholder holder) {
        try {

            mcamera.setpreviewdisplay(holder);
            mcamera.setpreviewcallback(this);
            camera.startpreview();
        } catch (ioexception e) {
        }
    }

    //释放camera
    public void releasecamera() {
        if (mcamera != null) {
            mcamera.setpreviewcallback(null);
            mcamera.stoppreview();// 停掉摄像头的预览
            mcamera.release();
            mcamera = null;
        }
    }

    //预览回调，传递yuv视频流数据
    @override
    public void onpreviewframe(byte[] bytes, camera camera) {
    //    log.i("onpreviewframe",""+ bytes);
        if(mcb!= null){
            mcb.ondecodeframe(bytes);
        }
    }
}            

 framecallback回调接口

public interface framecallback {
    void ondecodeframe(byte[] data) ;
}

mainactivity

public class mainactivity extends appcompatactivity implements framecallback{

    @override
    protected void oncreate(bundle savedinstancestate) {
        super.oncreate(savedinstancestate);
        setcontentview(r.layout.activity_main);
　　}

    @override
    public void ondecodeframe(byte[] data) {
　　　　　　//实时处理yuv视频流数据
    }

}

相关阅读

了解surfaceview

yuv数据格式相关转换方法