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Unregistered
October 13, 2002, 06:14:05
Hi All.

My request is for suggestions for the application of Image Control for the following tasks.

Language: VB or C

Problem:

A ccd board camera has been modified to send 2 fields at the end
of a long exposure capture ( longer than 1/50 secs )
The 2 fields ( even binned and odd binned ) are captured with
a WinTV PCI card ( BT848 )

Object:

To align the 2 fields to one 480 * 640 pixel picture frame
( ,bmp or jpg ) and display in live window. ( interlacing )

Add a number of these pictures and produce an averaged or
integrated picture of all the individual frames and be able
display the integrated picture as it is acquired and save this picture to disk after all frames have been integrated.

Be able to correct each captured frame by subtracting a
previous acquired special frame ( dark frame )

Exposure time of one frame: > .25 secs or 4 ( 8 ) fields / sec
Max number of frames to be summed < 256

I just like to get some idea whether this can be done with
this package,

My thanks in advance

Rein Smit


This message was originally posted by Rein A. Smit in the old IC Imaging Control Support Forum.

Unregistered
October 13, 2002, 06:46:53
Hello All,

Reading through thearchive I believe some more info might be
needed to answer the request.

The to be processed fields are initiated under program control
After the exposure time has passed the timing generator in the
CCD board is turned on and the first field that then is transfered out of the CCD is a long exposure integrated field
The second fiels is also somewhat under program control
( max 1/50 or as in my case max 1/60 of a second ) after
program command.

Regards

Rein Smit


This message was originally posted by Rein Smit in the old IC Imaging Control Support Forum.

Unregistered
October 13, 2002, 22:16:10
Hello,

Did you try to grab an image from your boardcamera using a BT878 based grabber ? If the camera does not send empty (balck) fields while the long time exposure is taking playce, the BT chip will not be able to grab the two fields.
If the camera sends out empty fields, you will have to grab frames continuously and find the frame that contains the long time exposure.

If you system works the second way, it should be possible to use IC solve the task.

Best regards
Johannes
IC Support


This message was originally posted by IC Support in the old IC Imaging Control Support Forum.

Unregistered
October 13, 2002, 23:26:36
Hello Johannes,

I am not sure whether the camera is sending black fields. The timing generator for the CCD is turned off to avoid the CCD from
discharging the wells. As soon as the timing generator is turned
on ( after the set exposure time ) the camera starts to send
fields and one perhaps the first one is the long exposure field that is to be used.

Is there a way to check for black field being sent?

Assuming that the camera is sending black fields how would one
detect the long exposure field and the other second one?


Regards

Rein Smit


This message was originally posted by Rein A. Smit in the old IC Imaging Control Support Forum.

Unregistered
October 14, 2002, 12:31:09
Hello,

At first you have to check whether the grabber can aquire images from your camera. To do so you have to connect the camera to the grabber and use a standard AVI capture program to record an imge stream to disk. If you play back the AVI file frame by frame, there have to be longtime exposed fields in every nth frame where n is dependent on the exposure time. If the camera does not sent emty frames, you will see only damaged image data or black images or no images.

Best regards
Johannes
IC Support


This message was originally posted by IC Support in the old IC Imaging Control Support Forum.