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Microphone port, for other input

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Ok, this is something that just hit me while I was cleaning up my shelf of general junk. Here is the basic question Is it possible to record none audio data through a microphone jack? And if so how many kb/sec can I pull through it. Now onto the details. I have a cable that converts audio jack style to TV Video style. Its the video-out for my digi-camera (I''m guessing they don''t use the normal video-out jack because of size).... I''m wondering if I could use this cable and my sound card with microphone capability to record video off my TV? I''ve never done any programming regarding interface, but right now I think the hardest part would be analge-digital conversion... and probably a low quality but thats ok. Any pointers would be great. I plan on testing anything by using the digi camera''s video out, and showing/recording the image that it would normally show on the TV screen. Pat - Ex nihilo nihilus

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Interesting.. I don''t have much experience with this sort of thing - it''s a hardware problem! - but my guess would be that the maximum sample rate that the audio in port allows (48kHz?) would be far too low to extract any meaningful information from a tv signal. I''ve never seen any software that allows you to digitise video through your sound card, which would hint that this is a no-go.

Try recording a sample and see if you can make out any patterns in the resulting waveform. You could do with a static test-card image to make life easier.

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Guest Anonymous Poster
This is probably a bad idea. There is a slight chance (very slight) that you could damage your hardware doing this, and if it can work, you''re going to have one helluva time trying to seperate the chroma and luma signals from data stored as digitized audio, which (most of the time) encodes a completely different kind of information than a video signal, and could result in some very difficult alignment issues due to your resolution.

Digitized video is typically not a ''byte image'' of a waveform (as audio is), it is instead usually something closer to a bitmap of each screen. What you''re suggesting could be done in theory if the mic port limits are high enough, but it would be extraordinarily difficult, on top of the fact that you''re going to have to deal with the sound card processing your signal before it even gets to you.

Also, an RCA jack is not necessarily an audio jack, they are quite standard for video signals.

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I''ve researched this a while back and I think video signals run @ ~ 2-5MHz. Most sound cards, however, can''t sample data that fast so video can''t be (accuratly) taken in ...... or something like that. Sorry, Its reallly hot in here and I''m finding it quite hard to think :\

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