多种方法获取相机最佳尺寸

/**
* 通过对比得到与宽高比最接近的尺寸（如果有相同尺寸，优先选择）
*
* @param surfaceWidth
*            需要被进行对比的原宽
* @param surfaceHeight
*            需要被进行对比的原高
* @param preSizeList
*            需要对比的预览尺寸列表
* @return 得到与原宽高比例最接近的尺寸
*/
protected Camera.Size getCloselyPreSize(int surfaceWidth, int surfaceHeight,
List<Camera.Size> preSizeList) {

int ReqTmpWidth;
int ReqTmpHeight;
// 当屏幕为垂直的时候需要把宽高值进行调换，保证宽大于高
//        if (mIsPortrait) {
//            ReqTmpWidth = surfaceHeight;
//            ReqTmpHeight = surfaceWidth;
//        } else {
ReqTmpWidth = surfaceWidth;
ReqTmpHeight = surfaceHeight;
//        }
//先查找preview中是否存在与surfaceview相同宽高的尺寸
for(Camera.Size size : preSizeList){
if((size.width == ReqTmpWidth) && (size.height == ReqTmpHeight)){
return size;
}
}

// 得到与传入的宽高比最接近的size
float reqRatio = ((float) ReqTmpWidth) / ReqTmpHeight;
float curRatio, deltaRatio;
float deltaRatioMin = Float.MAX_VALUE;
Camera.Size retSize = null;
for (Camera.Size size : preSizeList) {
curRatio = ((float) size.width) / size.height;
deltaRatio = Math.abs(reqRatio - curRatio);
if (deltaRatio < deltaRatioMin) {
deltaRatioMin = deltaRatio;
retSize = size;
}
}

return retSize;
}

List<Camera.Size> mSupportedPreviewSizes = mCamera.getParameters().getSupportedPictureSizes();
Camera.Size bestSize = getCloselyPreSize(1000,740,mSupportedPreviewSizes);
mWidth = bestSize.width;
mHeight = bestSize.height;

private int getPictureSize(List<Camera.Size> sizes) {
// 屏幕的宽度
int screenWidth = getResources().getDisplayMetrics().widthPixels;
LogUtil.d(TAG, "screenWidth=" + screenWidth);
int index = -1;

for (int i = 0; i < sizes.size(); i++) {
if (screenWidth == sizes.get(i).width) {
index = i;
}
}
// 当未找到与手机分辨率相等的数值,取列表中间的分辨率
if (index == -1) {
index = sizes.size() / 2;
}

return index;
}