Android 自定义相机(录像) 解决预览 照片方向问题
以下是自定义相机遇到的问题：
1. 相机预览的方向
2. 相机预览时图像变形
3. 照片保存到本地的方向
最近刚好公司的业务需要开发遥控拍照的功能，最初想通过调用系统的相机来解决，不过最后始终没找到让系统相机自动拍照的方法， 故只能改用 自定义相机来开发。当然也就发现了相机开发中的坑。
1 解决相机预览方向的问题：
/**
* 保证预览方向正确
*
* @param activity
* @param cameraId
* @param camera
*/
public static void setCameraDisplayOrientation(Activity activity, int cameraId, Camera camera) {
android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
android.hardware.Camera.getCameraInfo(cameraId, info);
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
int degrees = 0;
switch (rotation) {
case Surface.ROTATION_0:
degrees = 0;
break;
case Surface.ROTATION_90:
degrees = 90;
break;
case Surface.ROTATION_180:
degrees = 180;
break;
case Surface.ROTATION_270:
degrees = 270;
break;
}
int result;
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
result = (info.orientation + degrees) % 360;
result = (360 - result) % 360; // compensate the mirror
} else { // back-facing
result = (info.orientation - degrees + 360) % 360;
}
camera.setDisplayOrientation(result);
}2 解决相机预览变形的问题，相机在预览变形时肯定是因为 预览的宽高的比例 和 surfaceview设置的不一致
/**
* 设置Camera参数
*/
private void setCameraParameters() {
if (mCamera != null) {
mParameters = mCamera.getParameters();
List.Size> pictureSizeList = mParameters.getSupportedPictureSizes();
/* 从列表中选取合适的分辨率 */
Camera.Size picSize = CameraUtil.getProperSize4Ratio(pictureSizeList, (float) surfaceView.getHeight() / surfaceView.getWidth());
mParameters.setPictureSize(picSize.width, picSize.height);
Log.e("TAG","最终设置的picsize: picSize.width: " + picSize.width + " picSize.height: " + picSize.height);
List.Size> videoSiezes = mParameters.getSupportedVideoSizes();
int videoWidth = 0;
int videoHeight = 0;
if (videoSiezes != null && !videoSiezes.isEmpty()) {
// Camera.Size videoSize = VideoUtil.getInstance().getPropVideoSize(videoSiezes,surfaceView.getWidth());
Camera.Size videoSize = CameraUtil.getMaxSize4Width(videoSiezes,surfaceView.getWidth());
Log.e("TAG", "获取到的：video_width===" + videoSize.width + " video_height=== " + videoSize.height);
videoWidth = videoSize.width;
videoHeight = videoSize.height;
}
List.Size> previewSizes = mParameters.getSupportedPreviewSizes();
// Camera.Size previewSize = VideoUtil.getInstance().getPropPreviewSize(mParameters.getSupportedPreviewSizes(), videoWidth);
Camera.Size previewSize = CameraUtil.getProperSize4Ratio(previewSizes,(float) videoWidth / videoHeight);
mParameters.setPreviewSize(previewSize.width, previewSize.height);
Log.e(TAG, "最终设置的预览尺寸,previewSize.width: " + previewSize.width + " previewSize.height: " + previewSize.height);
List focusModes = mParameters.getSupportedFocusModes();
if (focusModes != null && focusModes.size() > 0) {
if (focusModes.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) {
mParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE); //设置自动对焦
}
}
mCamera.setParameters(mParameters);
}
} package com.beacool.beacoolcamera.utils;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import android.hardware.Camera.Size;
import android.util.Log;
public class CameraUtil {
/**
* 根据比例得到合适的尺寸的最大尺寸
*/
public static Size getProperSize4Ratio(List sizeList, float displayRatio) {
Collections.sort(sizeList, new SizeL2hComparator());
Size result = null;
for (Size size : sizeList) {
float curRatio = ((float) size.width) / size.height;
if (curRatio == displayRatio) {
result = size;
}
}
if (null == result) {
for (Size size : sizeList) {
float curRatio = ((float) size.width) / size.height;
if (curRatio == 3f / 4) {
result = size;
}
}
}
return result;
}
/**
* 根据宽度得到最大合适的尺寸
* @param sizeList
* @param Width
* @return
*/
public static Size getMaxSize4Width(List sizeList, int Width) {
// 先对传进来的size列表进行排序
Collections.sort(sizeList, new SizeL2hComparator());
Size result = null;
for (Size size : sizeList) {
if (size.height == Width) {
result = size;
}
}
return result;
}
/**
* 获取支持的最大尺寸
*/
public static Size getMaxSize(List sizeList) {
// 先对传进来的size列表进行排序
Collections.sort(sizeList, new SizeL2hComparator());
Size result = null;
if(sizeList != null && !sizeList.isEmpty()){
result = sizeList.get(sizeList.size() - 1);
}
return result;
}
/**
* 从小到大排序
*/
private static class SizeL2hComparator implements Comparator<Size> {
@Override
public int compare(Size size1, Size size2) {
if (size1.width < size2.width) {
return -1;
}else if (size1.width > size2.width) {
return 1;
}
return 0;
}
}
public static int getRecorderRotation(int cameraId){
android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
android.hardware.Camera.getCameraInfo(cameraId, info);
return info.orientation;
}
}
3 照片的保存方向，关于这个问题解决的方案很多，有把拍照的Bitmap进行旋转的再进行保存，但是这种比较耗时 特别是拍的照片比较大，则在旋转和保存都比较耗时；还有的是通过 ExifInterface 一下也给出代码：
/**
* 将图片的旋转角度置为0
*
* @param path
* @return void
* @Title: setPictureDegreeZero
* @date 2012-12-10 上午10:54:46
*/
public static void setPictureDegreeZero(String path) {
try {
ExifInterface exifInterface = new ExifInterface(path);
// 修正图片的旋转角度，设置其不旋转。这里也可以设置其旋转的角度，可以传值过去，
// 例如旋转90度，传值ExifInterface.ORIENTATION_ROTATE_90，需要将这个值转换为String类型的
exifInterface.setAttribute(ExifInterface.TAG_ORIENTATION, "" + ExifInterface.ORIENTATION_ROTATE_90);
exifInterface.saveAttributes();
} catch (IOException e) {
e.printStackTrace();
}
}我觉得还是通过方向的监听 IOrientationEventListener 来改变比较好 代码如下：
public class IOrientationEventListener extends OrientationEventListener {
public IOrientationEventListener(Context context) {
super(context);
}
@Override
public void onOrientationChanged(int orientation) {
if (ORIENTATION_UNKNOWN == orientation) {
return;
}
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(mCameraId, info);
orientation = (orientation + 45) / 90 * 90;
int rotation = 0;
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
rotation = (info.orientation - orientation + 360) % 360;
} else {
rotation = (info.orientation + orientation) % 360;
}
// Log.e("TAG","orientation: " + orientation);
if (null != mCamera) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setRotation(rotation);
mCamera.setParameters(parameters);
}
}
}只需要在 surfaceholder,callback 中的如下调用：
@Override
public void surfaceCreated(SurfaceHolder holder) {
startPreview();
orienListener.enable();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
releaseCamera();
orienListener.disable();
}