How can I work with Depth Data, offline?

edit

It depends on the format you were using. You can read video (AVI) files using theVideoCapture class , or a series of images with the imread function.

The problem with the Kinect sensor is that depth data ranges from 800 to 4000 (millimeters), which is outside the 8 bit (0-255) range. So the AVI file cannot store the real depth data, so only some image formats (TIFF and PNG) can be used to store these values (note: you have to use CV_LOAD_IMAGE_ANYDEPTH in the imread function). So I suggest to store the captured data as a series of images: the color as JPG (PNG or TIFF), the depth as 16 bit TIFF: color1.jpg,color2.jpg,...,depth1.tif,depth2.tif,...

Here is the code to read them

Mat depth,color;
int count=10; //number of depth images
char s[20];
for(int i=0;i<count;i++)
{
    sprintf(s,"depth%d.tif",i);
    depth=imread(s,CV_LOAD_IMAGE_ANYDEPTH);
    sprintf(s,"color%d.jpg",i);
    color=imread(s);
    //process the images...
}