Author Topic: Video capture device query  (Read 437 times)

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Online ComSoft6128

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Video capture device query
« on: 15:27, 02 January 21 »
Hi,


At present I'm using the OSSC and Hauppauge Rocket for video capture, for most usage this combination works fine.
But (always a but ::) ) some games, slideshows and demos will not record :(


So this brings me to these questions - how easy/hard/impossible would it be to build a CPC specific recording device that records in HD?
                                                      - Roughly what would be the component cost?


Now I know that this might be one of those "how long is a piece of string" questions and that throwing a couple of ASIC chips into a black box and shaking it about probably wouldn't give the desired result but I'd be interested in any responses.


Thanks,


Peter

Offline Bryce

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Re: Video capture device query
« Reply #1 on: 16:03, 02 January 21 »
The answer is - Almost impossible and incredibly expensive. The reason why is due to the fact that many games and demos change the frequency of the picture signal midway through the picture to create particular effects. This is possible on a real analogue CRT because it's not sampling the picture signal at a particular rate, it's just sending the signal directly to the CRT. On any digital device the electronics sample the signal as soon as a signal is connected and continues to sample the signal at that rate. Any change in frequency will then mess up the picture. To make a device that can do what the analogue circuitry does would require the hardware to read each scanline and then determine the pixel rate/position. With enough CPU power and speed it would be possible, but incredibly expensive.

Bryce.

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Re: Video capture device query
« Reply #2 on: 16:05, 02 January 21 »
Thanks for explaining that :(