怎么使用Android camera2 获取相机所有参数？

Question

怎么使用Android camera2 获取相机所有参数？

android camera  的方法是   param.flatten();

Answer 1

获取之后再进行设置，如下为kotlin写法

    //配置相机参数
    private fun initParameters(camera: Camera) {
        try {
            mParameters = camera.parameters
            mParameters.previewFormat = ImageFormat.NV21   //设置预览图片的格式

            //获取与指定宽高相等或最接近的尺寸
            //设置预览尺寸
            val bestPreviewSize = getBestSize(mSurfaceView.width, mSurfaceView.height, mParameters.supportedPreviewSizes)
            bestPreviewSize?.let {
                mParameters.setPreviewSize(it.width, it.height)
            }
            //设置保存图片尺寸
            val bestPicSize = getBestSize(picWidth, picHeight, mParameters.supportedPictureSizes)
            bestPicSize?.let {
                mParameters.setPictureSize(it.width, it.height)
            }
            //对焦模式
            if (isSupportFocus(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE))
                mParameters.focusMode = Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE

            camera.parameters = mParameters
        } catch (e: Exception) {
            e.printStackTrace()
            toast("相机初始化失败!")
        }
    }

       //获取与指定宽高相等或最接近的尺寸
    private fun getBestSize(targetWidth: Int, targetHeight: Int, sizeList: List<Camera.Size>): Camera.Size? {
        var bestSize: Camera.Size? = null
        var targetRatio = (targetHeight.toDouble() / targetWidth)  //目标大小的宽高比
        var minDiff = targetRatio

        for (size in sizeList) {
            var supportedRatio = (size.width.toDouble() / size.height)
            log("系统支持的尺寸 : ${size.width} * ${size.height} ,    比例$supportedRatio")
        }

        for (size in sizeList) {
            if (size.width == targetHeight && size.height == targetWidth) {
                bestSize = size
                break
            }
            var supportedRatio = (size.width.toDouble() / size.height)
            if (Math.abs(supportedRatio - targetRatio) < minDiff) {
                minDiff = Math.abs(supportedRatio - targetRatio)
                bestSize = size
            }
        }
        log("目标尺寸 ：$targetWidth * $targetHeight ，   比例  $targetRatio")
        log("最优尺寸 ：${bestSize?.height} * ${bestSize?.width}")
        return bestSize
    }