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Unregistered
October 31, 2005, 17:34:19
Hi all

What is a Anti-Aliasing filter? Hardware or Software?

I need 3 frame grabber card for x-ray acquisition.

Images need to be high quility and are greyscale.

If someone could please recommend a grame grabber card.

I amd going to write software for live video display and denoising and PLC control in VB (Don't know VC yet and have a deadline)

The x-ray guys said I have to have a anti-aliasing filter.

Thank you for your time
Bestbier

Johannes Vogel
October 31, 2005, 17:56:17
Hello,

What kind of video signal does the x-ray output? Is it a standard video signal or a high resolution non-standard signal ??

Bestbier
November 1, 2005, 12:25:25
Hi Johannes

The X-Ray machine has a image intesifier that converts the x-ray into light. This is captured by a standand B/W CCD camera. I think the resolution is 5??x3??, but I could be completly wrong. I will try and find the correct specs. I am using a Pinnacle entry level AV card in one machine but the picture is not very good, thats why I need good card this time.

Regards
Bestbier

Johannes Vogel
November 1, 2005, 16:12:20
What is the problem with the image quality ?
As far as I know, you do not scan moving objects with x-rays, right ? Therefore, an anti-aliasing filter does not make any sense.

Bestbier
November 2, 2005, 13:50:56
Hi Johannes

I found the specs of the camera:
High Resolution CCD Camera
756x581 pixels
625 lines
50 Hz
The x-ray images are greyscale, I don't know if the camera is colour.

The sensitivity of the Pinnacle card is not good enough(i think) - It is designed for capturing home movies. The contrast has to be very good as the defects we are looking for are very small.

The object under inspection does move. The image I need when it moves needs to be the same quality on my computer screen as it would be when I connect the camera directly to a video monitor. The object is then stopped at certain point and the image has to be enhanced and then saved. The image is very noisy and but by averaging all the pixels of about 10 frames a usable image will be generated.

The x-ray supplier supplies a system made by VisiConsult (www.visiconsult.com). If you supply your own PC it needs 1 PCI slot for the framegrabber card and 1 slot with a power cable for the anti-aliasing filter. This system is design for many uses with automatic or manual operation, zooming and rotating facilities, psuedo filter, etc. that I don't want.

Regards
Bestbier

Johannes Vogel
November 2, 2005, 14:11:38
Hello,
I suggest to use a digital FireWire camera and get rid of the analog stuff. We can offer a high res camera that works in progressive scan mode with out showing any interlaced effects offering a pixel resolution of 1024 x 768. For more information, please refer to:

http://www.1394imaging.com/en/products/cameras/firewire_mono/dmk31af03/overview/

Bestbier
November 2, 2005, 20:18:02
Hi

I would like to use a firewire camera, but I am building one new system and want to upgrade the one with the Pinnacle to be the same, since they are going to the same factory.

The cameras are also build into the image intesifier. We enquired about a firewire camera at the x-ray guys. Their response was that it would be to slow to view the object while it is moving and a extra cost of EUR2,200.

I think I will have to stick to analog.

Do you think you have a suitable frame grabber? and do I need the anti-aliasing?

Thanks for all your trouble

Regards
Bestbier

Johannes Vogel
November 3, 2005, 12:01:06
Hi,
If you follow the link above, you will see, that we offer a FireWire camera with mega pixel resolution that generates 30 full frames pre second for 590,--. You have to pay another 70,-- for a cable and a FireWire controller to get working system. This is far better than any analog solution and less expensive.

Bestbier
November 3, 2005, 13:08:03
Hi

I wish I could use the firewire camera, it should work perfectly. Unforunately the image intesifier has already been ordered by the client with the analog camera installed. I cannot change the camera because it is build inside the unit and I will void the warranty if I open it.

I have to use analog.

I future systems I will definately use firewire.

Regards
Bestbier

Johannes Vogel
November 3, 2005, 14:09:53
Hi,

Since the analog camera generates a standard video signal, you can use a standard frame grabber, such as our DFG/SV1:

http://www.1394imaging.com/en/products/grabbers/dfgsv1/overview/

Bestbier
November 8, 2005, 12:28:56
Hi

Can the DFG/SV1 flip the image horizontally?

Will place order for 3 cards soon.

Regards
Bestbier

Stefan Geissler
November 8, 2005, 14:50:17
Hello Bestbier,

The DFG/SV1 does not support flipping in hardware. Also the driver does not support flipping. This must be done by your software (which would cost CPU time)

Bestbier
November 8, 2005, 16:59:32
Hi Stefan

Do you have a card that supports flipping?

What is the difference between DGF/SV1 and DGF/SV1/LP?

Regards
Bestbier

Stefan Geissler
November 8, 2005, 17:03:32
Hello Bestbier,

as far as i know, there is no hardware, that does flipping.
The LP variant is a smaller built of the SV1.