java - Android Camera Preview - take only a part of the screen data -

i want take part of the screen data preview video callback reduce time of process. probleme know how take whole screen onpreviewframe:

@override public void onpreviewframe(byte[] data, camera camera) {         mydata = data;         // +get camera resolution x, y } 

and data image :

private bitmap getbitmapfromyuv(byte[] data, int width, int height) {     bytearrayoutputstream out = new bytearrayoutputstream();     yuvimage yuvimage = new yuvimage(data, imageformat.nv21, width, height, null);     yuvimage.compresstojpeg(new rect(0, 0, width, height), 100, out);      byte[] imagebytes = out.tobytearray();     bitmap image = bitmapfactory.decodebytearray(imagebytes, 0, imagebytes.length);      return image; } 

and take part of image taken want :

cutimage = bitmap.createbitmap(image, xoffset, yoffset, customwidth, customheight); 

the problem need take lots of images apply image processing on , that's why want reduce time takes images. instead of taking whole screen , crop it, want immediatly cropped image. there way part of screen data ?

ok found something, still record data of camera when using compresstojpeg crop picture custom rect. maybe there better before still improvement. here changes :

yuvimage.compresstojpeg(new rect(offsetx, offsety, sizecapturex + offsetx, sizecapturey + offsety ), 100, out);