我有以下代码块来从前置摄像头捕获图片并将其存储到存储中。以下代码适用于我尝试过的所有设备（Samsung Galaxy S2、Note 2、Micromax Canvas 2、HD、Sony Xperia U），但 jpegcallback 返回的“数据”在 HTC One X 上始终为空。任何想法为什么?
public void takePicture () {
Log.d("camera","taking picture");
// do we have a camera?
if (cameraIsOk()) {
Log.d("camera","waiting 1");
try {
synchronized (this) {
wait(2000);
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
Log.d("camera", "Waiting didnt work!!");
e.printStackTrace();
}
if (myCamera == null)
myCamera = Camera.open(camId);
if (myCamera != null)
{
Log.d("camera","surface view");
SurfaceView surfaceView = new SurfaceView(context);
surfaceView.setFocusable(true);
Log.d("camera","getting holder");
SurfaceHolder holder = surfaceView.getHolder();
Log.d("camera","add callback");
holder.addCallback(this);
Log.d("camera","set type");
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
try {
Log.d("camera","get parameters");
Camera.Parameters parameters = myCamera.getParameters();
Log.d("camera","get supported preview size");
List<Size> sizes = parameters.getSupportedPreviewSizes();
Size optimalSize = GBCameraUtil.getOptimalPreviewSize(sizes, 1024, 768);
int sdkBuildVersion = Integer.parseInt( android.os.Build.VERSION.SDK );
if (sdkBuildVersion < 5 || usingLandscape)
{
// Picture size should be landscape
if (optimalSize.width < optimalSize.height || usingLandscape)
parameters.setPictureSize( optimalSize.height, optimalSize.width );
else
parameters.setPictureSize( optimalSize.width, optimalSize.height );
}
else
{
// If the device is in portraint and width > height,
// or if the device is in landscape and height > height, so we need to rotate them.
switch (context.getResources().getConfiguration().orientation) {
case ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE :
if (optimalSize.height > optimalSize.width ) {
parameters.setRotation(camId == GBCameraUtil.findFrontFacingCamera() ? 270 : 90);
}
break;
case ActivityInfo.SCREEN_ORIENTATION_PORTRAIT :
if (optimalSize.width > optimalSize.height) {
parameters.setRotation(camId == GBCameraUtil.findFrontFacingCamera() ? 270 : 90);
}
break;
}
parameters.setPictureSize (optimalSize.width, optimalSize.height);
}
Log.d("camera","set param");
myCamera.setParameters(parameters);
Log.d("camera","set preview disp");
myCamera.setPreviewDisplay(holder);
Log.d("camera","start preview");
myCamera.startPreview();
Log.d("camera","take picture");
myCamera.takePicture(null, null, getJpegCallback());
} catch (Exception e) {
// Sorry, nothing to do
}
}
}
}
private PictureCallback getJpegCallback(){
PictureCallback jpeg=new PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
myCamera.stopPreview();
mPreviewRunning = false;
Log.d("camera","pic taken");
if (data != null) {
Toast.makeText(context, "data not null ", Toast.LENGTH_LONG).show();
Log.d("camera","data not null. Filename is :" + fileName);
FileOutputStream fos;
try {
if (fileName.equals("")) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
String date = dateFormat.format(new Date());
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
fileName = Environment.getExternalStorageDirectory().getAbsolutePath() + "/" + "picture" + date + ".jpg";
}
else{
Toast.makeText(context, "storing to internal " , Toast.LENGTH_LONG).show();
// fileName = Environment.getDataDirectory().getAbsolutePath() + "/" + "picture" + date + ".jpg";
fileName = context.getFilesDir().getAbsolutePath()+ "/" + "unlocked" + date + ".jpg";
}
Toast.makeText(context, "filename " + fileName, Toast.LENGTH_LONG).show();
Log.d("camera","filename is : " + fileName);
}
Log.d("camera","coming here");
fos = new FileOutputStream(new File(fileName));
Log.d("camera","writing data");
fos.write(data);
Log.d("camera","written data");
fos.close();
} catch (IOException e) {
//do something about it
Log.d("camera","some exception"+ e);
}
}
else
Toast.makeText(context, "data null " , Toast.LENGTH_LONG).show();
myCamera.release();
myCamera = null;
}
};
return jpeg;
}