我试图从相机的预览中获取byte [],将其转换为位图并使用imageView.setImageBitmap()在imageview上显示它
我已经设法开始预览并将其显示在surfaceView上,但我不知道如何在RGB位图中转换byte []数据(我认为是Yuv格式)以在imageView上显示它.
我正在尝试的代码如下:
camera = camera.open(); parameters = camera.getParameters(); camera.setParameters(parameters); surfaceHolder = surfaceView.getHolder(); surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); camera.setPreviewDisplay(surfaceHolder); camera.setPreviewCallback(this); camera.startPreview();
并且预览回调就是这个
@Override public void onPreviewFrame(byte[] data, Camera camera) { Camera.Parameters parameters = camera.getParameters(); int width = parameters.getPreviewSize().width; int height = parameters.getPreviewSize().height; ByteArrayOutputStream outstr = new ByteArrayOutputStream(); Rect rect = new Rect(0, 0, width, height); YuvImage yuvimage=new YuvImage(data,ImageFormat.NV21,width,height,null); yuvimage.compressToJpeg(rect, 100, outstr); Bitmap bmp = BitmapFactory.decodeByteArray(outstr.toByteArray(), 0, outstr.size()); imgView1.setImageBitmap(bmp); }
预览有效但imageView仍为空
任何的想法?
您可能没有在UI线程中打开相机.但是,您需要确保在UI线程中调用setImageBitmap:
@Override public void onPreviewFrame(final byte[] data, Camera camera) { Camera.Parameters parameters = camera.getParameters(); int width = parameters.getPreviewSize().width; int height = parameters.getPreviewSize().height; YuvImage yuv = new YuvImage(data, parameters.getPreviewFormat(), width, height, null); ByteArrayOutputStream out = new ByteArrayOutputStream(); yuv.compressToJpeg(new Rect(0, 0, width, height), 50, out); byte[] bytes = out.toByteArray(); final Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length); MyActivity.this.runOnUiThread(new Runnable() { @Override public void run() { ((ImageView) findViewById(R.id.loopback)).setImageBitmap(bitmap); } }); }