我一直试图弄清楚一段时间,但由于某种原因,当我开始使用相机录制视频时,预览放大.我从以下示例中获取以下代码：
@Override
public void surfaceChanged(SurfaceHolder holder,int format,int width,int height) {
Camera.Parameters myParameters = mCamera.getParameters();
List<Camera.Size> sizes = myParameters.getSupportedPreviewSizes();
Camera.Size myBestSize = getBestPreviewSize(sizes,width,height);
if (myBestSize != null) {
myParameters.setPreviewSize(myBestSize.width,myBestSize.height);
myParameters.setVideoStabilization(false);
mCamera.setParameters(myParameters);
mCamera.startPreview();
mCamera.unlock();
}
}
private Camera.Size getBestPreviewSize(List<Camera.Size> sizes,int height) {
final double ASPECT_TOLERANCE = 0.05;
double targetRatio = (double) width / height;
if (sizes == null) return null;
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = height;
// Find size
for (Camera.Size size : sizes) {
double ratio = (double) size.width / size.height;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Camera.Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
但录制视频时,预览仍会放大.我尝试手动将预览大小设置为1280×720,但是它在我测试的所有设备上都不起作用,有些显示黑色的SurfaceView.
录制视频时有什么办法阻止预览放大吗？ StackOverflow中的这些解决方案都不会似乎有效.
编辑：我尝试使用自己的onMesaure方法创建了一个自定义的SurfaceView,但是当我启动MediaRecorder时,我收到一个-19错误. (不顾赏金中的-16)
解决方法
我对您所谈论的缩放类型感到困惑,可能是一个软件缩放,或者可能是自动对焦,所以我会提出不同的潜在提示,导致最终的解决方案：
>实现mCamera.setZoomChangeListener,例如：
mCamera.setZoomChangeListener(new Camera.OnZoomChangeListener() {
@Override public void onZoomChange(int i,boolean b,Camera camera) {
Log.e("StackOverflow","Zoom just changed !");
// Inspect things from here
}
});
>禁用平滑缩放：
mCamera.stopSmoothZoom(); // My device doesn't support it,but maybe your device does
>检查所有的相机Camera.Parameters：
Log.e("StackOverflow","All Camera parameters :");
for(String s : mCamera.getParameters().flatten().split(";"))
Log.e("StackOverflow",s + "\n");
>然后切换可以缩放相关的任何东西,例如：
Camera.Parameters parameters = mCamera.getParameters(); parameters.setZoom(100); // My device support some values in the range 100 | 400 parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_INFINITY); parameters.setVideoStabilization(false); // Don't forget to add the new parameters to the camera : mCamera.setParameters(parameters);
问候
