Cheap hardware to capture closed captions?

[doncaruana]

My old ATI 750 usb died on me. I was using graphstudio and ccextractor to get a bin file and pull srt captions through a composite video feed successfully for a while.

Can anyone give me any recommendations on some replacement hardware? I bought this cheapo device on Amazon but it didn't have any extra software and I can't quite figure out how to make it work like the diamond did.

Any help would be greatly appreciated.

[Cornucopia]

NTSC Closed captions reside on line 21, which is in the VBI (vertical blanking interval). NTSC has 525 lines (more accurately, 2 fields of 262.5 lines), of which, the middle 483 are "visible, active picture".

Standard consumer digital capture cards usually only capture (for NTSC system) 480 visible picture lines, starting with line 22 (or 23?). Pro capture cards capture 486 NTSC lines, starting at 19 (or 20?). Alternate option there depends on how the card decides the 1/2 lines at beginning & end.
Notice: for consumer cards, it misses line 21 altogether, while pro cards do not.

So, you need to find a card that supports capturing 486 lines (or one that captures 480, but specifically pre-captures line 21 and converts it - rare). Blackmagic & Aja cards do, as does Osprey. Not sure about the others, someone else will have to list...


Scott

[dellsam34]

Most legacy capture cards do capture the entire 525 scan lines, they just spit out 480 for video, A software is needed to access those scan lines to extract caption as the OP was doing with his ATI 750, People who can answer the OP question are people who are into this kind of stuff, I would join a teletext or caption forum to get the right answer. As far as I know the Diamond Multimedia TVW750USB TV Wonder 750 USB can be still purchased online.

[doncaruana]

I think this is largely a function of the drivers. No idea where a teletext or caption forum is. Guess I can look around.

[dellsam34]

Yes a driver, but without a special software you wouldn't have access to those lines, There are members here who have the Diamond Multimedia TVW750USB TV Wonder 750 USB, maybe one them can check this out for you before you buy one.