Question

当我显示相机预览时，它会拉伸所以，我搜索并找到了一些东西。但它不能很好地运作。我正在使用surfaceView进行显示预览。这是我正在使用的代码。

getOptimalPreviewSize

private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
    final double ASPECT_TOLERANCE = 0.1;
    double targetRatio=(double)h / w;

    if (sizes == null) return null;

    Camera.Size optimalSize = null;
    double minDiff = Double.MAX_VALUE;

    int targetHeight = h;

    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);
            }
        }
    }
    Log.i(TAG, "width = "+ optimalSize.width +" height = "+ optimalSize.height);
    return optimalSize;
}

surfaceChanged

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    Log.i(TAG, "surfaceChanged : width = "+width +" height = "+height);
    if (mSupportedPreviewSizes != null) {
        Log.i(TAG, "mSupportedPreviewSizes");

        // Get Optimal Preview Size
        mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);

        // Setting the optimal preview for best result
        if(mPreviewSize != null) {
            Log.i(TAG, "Activate Optimal Preview");
            Camera.Parameters parameters = mCamera.getParameters();
            parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
            mCamera.setParameters(parameters);
            mCamera.startPreview();
        }

    }h
}

日志

  surfaceChanged : width = 720 height = 1134

  optimalPreviewSize width = 800 height = 480

如您所见，width和height不相同，我认为这就是为什么这不是显示预览效果好的原因。我能为此做些什么我是android的新手。

Answer 1

我发现了一个错误：

if (Math.abs(size.height - targetHeight) < minDiff) {

相机预览尺寸为横向布局尺寸。所以size.height实际上是设备宽度。但targetHeight是视图高度（通常视图是设备大小）。修复

targetHeight = Math.min(w, h)

你可以找到谷歌演示代码GoogleDemoCode

获取Android中相机的最佳预览尺寸

1 个答案: