User`s guide

2 Introduction
Argument Description
A data structure containing the following fields:
Data
Current image frame specified as an
H-by-W-by-B array, where H is the image
height and W is the image width, as
specified in the
ROIPosition property, a nd
B is the number of color bands, as specified
in the
NumberOfBands property
Resolution
Text string specifying the current image
width and height, as defined by the
ROIPosition property
Status
String describing the status of the video
input object
event
Timestamp
String specifying the time associated with
the current image frame, in the format
hh:mm:ss:ms
himage
Handle to the image object in which the data is to be
displayed
The following example creates an update preview window function that
displays the timestamp of each incoming video frame as a text label in the
custom GUI. The update p review window function uses
getappdata to
retrieve a handle to the text label
uicontrol object from application-defined
data in the im age object. The custom GU Istoresthishandletothetextlabel
uicontrol object — see “Specifying the Update Prev ie w Function” on page
2-15.
Note that the update preview window function also displays the video data by
updating the
CData of the image object.
function mypreview _fcn (obj,event,himage)
% Example update preview w ind ow f unct ion.
% Get timestamp for frame.
tstampstr = event.Time stamp;
% Get handle to text label uicontrol.
2-14