原因：android手机厂商太多，ROM定制化太严重，给我们码农带了诸多不便。
Android的拍照功能的实现：
1.调用系统的相机：
步骤1：
public void openCamera(View view) {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
mImagePath = FileUtil.genSystemCameraPhotoPath();
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(mImagePath)));
startActivityForResult(intent, REQUST_CODE_CAMERA);
}
case R.id.button1://第一种方法，获取压缩图
Intent intent1 = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// 启动相机
startActivityForResult(intent1, REQUEST_THUMBNAIL);
break;
case R.id.button2://第二种方法，获取原图
Intent intent2 = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
Uri uri = Uri.fromFile(new File(picPath));
//为拍摄的图片指定一个存储的路径
intent2.putExtra(MediaStore.EXTRA_OUTPUT, uri);
startActivityForResult(intent2, REQUEST_ORIGINAL);
break;
步骤2：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == REQUEST_THUMBNAIL) {//对应第一种方法
/**
* 通过这种方法取出的拍摄会默认压缩，因为如果相机的像素比较高拍摄出来的图会比较高清，
* 如果图太大会造成内存溢出（OOM），因此此种方法会默认给图片压缩 ,坦白说拿到的就是一个缩略 图
*/
Bundle bundle = data.getExtras();
Bitmap bitmap = (Bitmap) bundle.get("data");
mImageView.setImageBitmap(bitmap);
}
else if(resultCode == REQUEST_ORIGINAL){//对应第二种方法
/**
* 这种方法是通过内存卡的路径进行读取图片，所以的到的图片是拍摄的原图
*/
result = BitmapFactory.decodeFile(picPath);
}
}
}
}
2.自定义的相机：
这个就简单提下
a.新建一个class extends SurfaceView
b.在其构造方法里面init一些基本的属性，增加回调 getHolder().addCallback(callback);
private SurfaceHolder.Callback callback = new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
openCamera(mCameraFacing); // 1.打开相机
initParameters(); // 2.设置相机参数
mCamera.setPreviewDisplay(getHolder()); // 3.设置预览显示的Surface
} catch (Exception e) {
Toast.makeText(getContext(), "打开相机失败", Toast.LENGTH_SHORT).show();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
updateCamera(); // 4.更新相机属性，每次更换分辨率需要更新的操作，包括设置预览大小和方向，开始预览
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
releaseCamera(); // 5.释放相机资源
}
};
c.差不多就a,b了，哈哈。。。
这里只说下可能出现的旋转问题（比如三星七八手机逆时针旋转了90度）：
既然照片存储的时候是歪的，那我们显示的时候就必须转正了，如何操作呢？
请看下步：
----------------->>>>>>> 旋转问题全家桶 <<<<<<<--------------------
法子1：旋转JPEG byte[]类型的图片(适合自定义相机拍出来回调的照片，PictureCallback里面)
// 在 Android 4.1.1 的 Camera 源码中找到
// Returns the degrees in clockwise. Values are 0, 90, 180, or 270.
public static int getOrientation(byte[] jpeg) {
if (jpeg == null) {
return 0;
}
int offset = 0;
int length = 0;
// ISO/IEC 10918-1:1993(E)
while (offset + 3 < jpeg.length && (jpeg[offset++] & 0xFF) == 0xFF) {
int marker = jpeg[offset] & 0xFF;
// Check if the marker is a padding.
if (marker == 0xFF) {
continue;
}
offset++;
// Check if the marker is SOI or TEM.
if (marker == 0xD8 || marker == 0x01) {
continue;
}
// Check if the marker is EOI or SOS.
if (marker == 0xD9 || marker == 0xDA) {
break;
}
// Get the length and check if it is reasonable.
length = pack(jpeg, offset, 2, false);
if (length < 2 || offset + length > jpeg.length) {
return 0;
}
// Break if the marker is EXIF in APP1.
if (marker == 0xE1 && length >= 8 &&
pack(jpeg, offset + 2, 4, false) == 0x45786966 &&
pack(jpeg, offset + 6, 2, false) == 0) {
offset += 8;
length -= 8;
break;
}
// Skip other markers.
offset += length;
length = 0;
}
// JEITA CP-3451 Exif Version 2.2
if (length > 8) {
// Identify the byte order.
int tag = pack(jpeg, offset, 4, false);
if (tag != 0x49492A00 && tag != 0x4D4D002A) {
return 0;
}
boolean littleEndian = (tag == 0x49492A00);
// Get the offset and check if it is reasonable.
int count = pack(jpeg, offset + 4, 4, littleEndian) + 2;
if (count < 10 || count > length) {
return 0;
}
offset += count;
length -= count;
// Get the count and go through all the elements.
count = pack(jpeg, offset - 2, 2, littleEndian);
while (count-- > 0 && length >= 12) {
// Get the tag and check if it is orientation.
tag = pack(jpeg, offset, 2, littleEndian);
if (tag == 0x0112) {
// We do not really care about type and count, do we?
int orientation = pack(jpeg, offset + 8, 2, littleEndian);
switch (orientation) {
case 1:
return 0;
case 3:
return 180;
case 6:
return 90;
case 8:
return 270;
}
return 0;
}
offset += 12;
length -= 12;
}
}
return 0;
}
法子2：旋转从指定Path拿出来的图片
public static int readPictureDegree(String path) {
int degree = 0;
try {
ExifInterface exifInterface = new ExifInterface(path);
int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_90:
degree = 90;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
degree = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_270:
degree = 270;
break;
case ExifInterface.ORIENTATION_FLIP_HORIZONTAL:
degree = 0;
break;
case ExifInterface.ORIENTATION_FLIP_VERTICAL:
degree = 180;
break;
case ExifInterface.ORIENTATION_TRANSPOSE:
degree = 90;
break;
case ExifInterface.ORIENTATION_TRANSVERSE:
degree = 270;
break;
}
} catch (IOException e) {
e.printStackTrace();
}
return degree;
}
法子3：旋转原始预览数据NV21（相机预览回调函数PreviewCallback）
private byte[] rotateYUV420Degree90(byte[] data, int imageWidth, int imageHeight)
{
byte [] yuv = new byte[imageWidth*imageHeight*3/2];
// Rotate the Y luma
int i = 0;
for(int x = 0;x < imageWidth;x++)
{
for(int y = imageHeight-1;y >= 0;y--)
{
yuv[i] = data[y*imageWidth+x];
i++;
}
}
// Rotate the U and V color components
i = imageWidth*imageHeight*3/2-1;
for(int x = imageWidth-1;x > 0;x=x-2)
{
for(int y = 0;y < imageHeight/2;y++)
{
yuv[i] = data[(imageWidth*imageHeight)+(y*imageWidth)+x];
i--;
yuv[i] = data[(imageWidth*imageHeight)+(y*imageWidth)+(x-1)];
i--;
}
}
return yuv;
}
法子4：旋转的就是一个bitmap
@Override
public void onPictureTaken(byte[] data, Camera camera) {
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
Matrix matrix = new Matrix();
matrix.preRotate(rotate);
bitmap = Bitmap.createBitmap(bitmap ,0,0, bitmap .getWidth(), bitmap
.getHeight(),matrix,true);
};
旋转完后可能还会有个镜像的问题(比如前置的摄像头)
Matrix matrix = new Matrix();
matrix.postScale(-1, 1);
bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
拍照的坑就赞告一段落了。休息一会儿吧，骚年。生命诚可贵！！！
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Android的图库选图的坑：
续
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