[AG-TECH] Image quality

[Natalia Costas Lago]

Thank you for the hints, in xawtv the image is not that bad, but in VIC it's
terrible (colors and definition), it doesnt make much difference to increase
quality and bandwith to the maximun. I was wondering wich tricks or codecs
do people use. Am I wrong in my thought about h261 being the only codec
available to AG2.1.2?


> Nothing about your equipment, of itself, should cause any major
> image quality deterioration.  Of course, if the camera has been
> used before and left pointed at a bright source for a long time,
> say in a surveillance role, it could be the problem.  Equally if
> someone has set up the monitors for a particular application, they
> could be the problem.  If you have a decent AV department around,
> you could try to eliminate the camera as the problem by plugging
> in a video signal generator instead, with it set to colour bars,
> and see how they come out - they should really shine on a PC
> monitor.  If they do, then try a different camera.  If they don't, look
> at the display side of things.  Make sure you don't have any
> excessive cable runs - many cameras don't have very powerful output
> drivers and the first thing to go can be colour.  Also check you
> are using proper video cable from camera to capture card - an
> underspecified cable will lose high frequencies (say above 3 MHz)
> more than lower ones, and so reduce the colour information.
>
> Cheers
>
> Chris
>
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>> -----Original Message-----
>> From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov]On
>> Behalf Of Natalia Costas Lago
>> Sent: 13 May 2004 08:43
>> To: ag-tech at mcs.anl.gov
>> Subject: [AG-TECH] Image quality
>>
>>
>>
>>
>> Hi all,
>>
>>
>> We have noticed that image color in our videostream seems to
>> have a lack of
>> ....accuracy to reality... i've seen other video streams that seem to
>> reflect colors better and probably in a more real way. I was
>> wondering where
>> in the chain we can fix that. We are using a provisional Sony EVI D30
>> camera, pinnacle pctv pro capture cards (i've tried as well
>> with osprey 500,
>> osprey 100 and hauppauge wintv go). Our display grahpics card
>> is a nvidia
>> quadro nvs and, finally, our display right now is composed of
>> a brand new
>> fujitsu TFT and a plasma TV.
>>
>> The codecs we are using are h261 (i think h263 cant be used
>> with AG2.1.2 so
>> far, is there any date about when will it be available?).
>>
>> Can anyone give us a piece of advice where we can improve our
>> video quality?
>>
>> Kind regards and thank you in advance.
>> Natalia.
>>
>>
>> -----------------------------------
>> Natalia Costas Lago
>> email: natalia at cesga.es
>>
>> Centro de Supercomputacion de Galicia (CESGA)
>> Avenida de Vigo, s/n Campus Sur
>> 15705 Santiago de Compostela - SPAIN
>> Tel:   +34  981 56 98 10
>> Fax:  +34  981 59 46 16
>> http://www.cesga.es/
>>
>>



-----------------------------------
Natalia Costas Lago
mailto: natalia at cesga.es

Centro de Supercomputacion de Galicia (CESGA)
Avenida de Vigo, s/n Campus Sur
15705 Santiago de Compostela - SPAIN
Tel: +34  981 56 98 10
Fax: +34  981 59 46 16
http://www.cesga.es/