Android Camera实现毫秒级拍照实例

我们知道自定义camera需要以下几步

1. 打开相机，即实例化camera对象，camera camera = camera.open();
2. 设置camera的相关参数，camera.parameters parameters = camera.getparameters();
3. 打开预览，camera.setpreviewdisplay(surfaceholder); camera.startpreview();
4. 获取图片，这里只是从预览中获取因此使用，camera.setpreviewcallback(new camera.previewcallback(){……..});
5. 停止预览，释放相机，camera.stoppreview();camera.release();

1、打开相机

public static camera openfacingbackcamera() {
    camera cam = null;
    camera.camerainfo camerainfo = new camera.camerainfo();
    for (int camidx = 0, cameracount = camera.getnumberofcameras(); camidx < cameracount; camidx++) {
      camera.getcamerainfo(camidx, camerainfo);
      if (camerainfo.facing == camera.camerainfo.camera_facing_front) {
        try {
          //打开相应的摄像头，目前是前置摄像头
          cam = camera.open(camidx);
        } catch (runtimeexception e) {
          e.printstacktrace();
          if (cam!=null){
            cam.stoppreview();
            cam.release();
          }
          cam = null;
        }
      }
    }
    return cam;
  }

2、设置相关参数和预览

//定义surfaceview
private surfaceview localsurface;
 // 为surfaceholder添加一个回调监听器
    localsurface.getholder().addcallback(new surfaceholder.callback() {
      @override
      public void surfacecreated(surfaceholder holder) {

      }

      @override
      public void surfacechanged(surfaceholder holder, int format, int width, int height) {
        camera = camerautil.openfacingbackcamera();
        //设置相机预览旋转角度
        camera.setdisplayorientation(180);
        if (camera != null) {
          camera.parameters parameters = camera.getparameters();// 获得相机参数
          list<camera.size> sizes = parameters.getsupportedpreviewsizes();
          list<camera.size> sizes_pic = parameters.getsupportedpicturesizes();
          camera.size cs = sizes.get(0);
          int mwidth = cs.width;
          int mheight = cs.height;
          parameters.setpreviewsize(mwidth, mheight);
          parameters.setpicturesize(sizes_pic.get(0).width, sizes_pic.get(0).height);
          parameters.setjpegquality(85);//
          parameters.setfocusmode(camera.parameters.focus_mode_auto);
          parameters.setpictureformat(imageformat.jpeg);
          camera.setparameters(parameters);
          try {
            camera.setpreviewdisplay(localsurface.getholder());
            camera.startpreview(); // 开始预览
            camera.autofocus(null); // 自动对焦
          } catch (ioexception e) {
            e.printstacktrace();
            camera.stoppreview();
            camera.release();
            camera = null;
          }
        }
      }

      @override
      public void surfacedestroyed(surfaceholder holder) {
        if (camera!=null){
          camera.stoppreview();
          camera.release();
          camera = null;
        }
      }
    } );
    // 设置该surfaceview自己不维护缓冲
    localsurface.getholder().settype(surfaceholder.surface_type_push_buffers);

3、获取图片

 private void getviewimage() {
   //设置监听
    camera.setpreviewcallback(new camera.previewcallback(){

      @override
      public void onpreviewframe(byte[] data, camera camera) {
        camera.size size = camera.getparameters().getpreviewsize();
        try{
          yuvimage image = new yuvimage(data, imageformat.nv21, size.width, size.height, null);
          if(image!=null){
            bytearrayoutputstream stream = new bytearrayoutputstream();
            image.compresstojpeg(new rect(0, 0, size.width, size.height), 80, stream);
            bitmap bmp = bitmapfactory.decodebytearray(stream.tobytearray(), 0, stream.size());
            //因为图片会放生旋转，因此要对图片进行旋转到和手机在一个方向上
            rotatebitmap(bmp);
            stream.close();
          }
        }catch(exception ex){
          log.e("sys","error:"+ex.getmessage());
        }
      }
    });
  }

旋转图片的方法

public void rotatemybitmap(bitmap bmp){
    matrix matrix = new matrix();
    matrix.postscale(-1, 1); // 镜像水平翻转(如果左右颠倒)
    matrix.postrotate(180);
    bitmap nbmp = bitmap.createbitmap(bmp, 0,0, bmp.getwidth(), bmp.getheight(), matrix, true);
    imageview.setimagebitmap(nbmp);
  };

自定义时间拍照

  private handler mhandler = new handler() {
    public void handlemessage(message msg) {
      switch (msg.what) {
        case 101:
          getviewimage();
          log.e(tag, "handlemessage: 拍照" );
          mhandler.sendemptymessagedelayed(102, 100);
          break;
        case 102:
          camera.setpreviewcallback(null);
          break ;
      }
    }
  };

然后点击按钮调用

mhandler.sendemptymessagedelayed(101, 100);

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。