如何设置android camera2预览和捕获大小？

Question

我用a SurfaceView来显示我捕获的预览.我想使用width = 1080,height = 1920进行预览.我在哪里可以设置预览的大小？

我用谷歌搜索了一个答案,但它们都是用于相机版本的.我使用的是android.hardware.camera2.

private void takePreview() {
    try {
        final CaptureRequest.Builder previewRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
        previewRequestBuilder.addTarget(mSurfaceHolder.getSurface());
        mCameraDevice.createCaptureSession(Arrays.asList(mSurfaceHolder.getSurface(), mImageReader.getSurface()), new CameraCaptureSession.StateCallback() // ?
        {
            @Override
            public void onConfigured(CameraCaptureSession cameraCaptureSession) {
                if (null == mCameraDevice) return;
                mCameraCaptureSession = cameraCaptureSession;
                try {
                    previewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
                    previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_ALWAYS_FLASH);
                    previewRequestBuilder.set(CaptureRequest.JPEG_THUMBNAIL_SIZE, new Size(1080,1920));

                    CaptureRequest previewRequest = previewRequestBuilder.build();
                    mCameraCaptureSession.setRepeatingRequest(previewRequest, null, childHandler);
                } catch (CameraAccessException e) {
                    Log.e("takePreview","onConfigured(CameraCaptureSession cameraCaptureSession)",e);
                }
            }
            @Override
            public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) {
                Log.e("takePreview","onConfigureFailed");
            }
        }, childHandler);
    } catch (CameraAccessException e) {
        Log.e("takePreview","CameraAccessException");
    }
}

Answer 1

如createCaptureSession的引用中所述:

对于绘制到SurfaceView:创建SurfaceView的Surface后,使用setFixedSize(int,int)将Surface的大小设置为getOutputSizes(SurfaceHolder.class)返回的大小之一,然后通过调用getSurface()获取Surface .如果应用程序未设置大小,则摄像机设备将舍入到最接近支持的小于1080p的大小.

Answer 2

看一下 Google 在 GitHub 上提供的 Camera2Basic 示例： https: //github.com/googlesamples/android-Camera2Basic

主片段中有一个方法可以为给定设备选择最佳预览尺寸。如果您想让您的应用程序更加灵活，而不是对大小进行硬编码，这可能是一个更好的方法，但即使您仍然愿意坚持使用设定的大小，您也可以看到它们如何使用结果。

总而言之，您只需将 TextureView 的大小设置为您想要的任何预览大小。

方法名称是“chooseOptimalSize”，它包含以下注释/解释：

/**
     * Given {@code choices} of {@code Size}s supported by a camera, choose the smallest one that
     * is at least as large as the respective texture view size, and that is at most as large as the
     * respective max size, and whose aspect ratio matches with the specified value. If such size
     * doesn't exist, choose the largest one that is at most as large as the respective max size,
     * and whose aspect ratio matches with the specified value.
     *
     * @param choices           The list of sizes that the camera supports for the intended output
     *                          class
     * @param textureViewWidth  The width of the texture view relative to sensor coordinate
     * @param textureViewHeight The height of the texture view relative to sensor coordinate
     * @param maxWidth          The maximum width that can be chosen
     * @param maxHeight         The maximum height that can be chosen
     * @param aspectRatio       The aspect ratio
     * @return The optimal {@code Size}, or an arbitrary one if none were big enough
     */