Posted by AnthonyR on 10/01/05 17:43

"Jona Vark" <noemail@all.com> wrote in message
news:SDl%e.2114$rl1.1263@newssvr27.news.prodigy.net...
>
> "Tony" <trusso11783@yahoo.com> wrote in message
> news:54rmj1de2ua906t2g92vg3rgej1v9t3ri8@4ax.com...
>> On Mon, 19 Sep 2005 18:33:45 GMT, "Jona Vark" <noemail@all.com> wrote:
>>
>> >if you were able to capture raw data from the CCD it would be nearly
>> >unviewable. That said.. it would be a very difficult task indeed..
>> >considering DV's 5:1 compression ratio you would be looking at a 125Mbs
> data
>> >stream which would need sufficient tweaking to make it viewable at all.
>>
>> What are you talking about. I have been capturing uncompressed video
>> since
> 1999 using my Toaster NT.
>> I had to be able to capture 22 MB/sec. SInce there is no compression, it
> requires 1 GB /minute. And
>> I was able to edit up to 4 tracks (Layers) at a time. I would output to
> either S VHS, miniDV or DVD
>>
>
>
> Pay attention! I was talking about getting a 125Mb/s data down a 25Mb/s
> format (DV).
>
>
>
>
>
OK, Thanks for the replies, i got the little b and big B now. :)
But I wonder to the OP question, if it would still be possible since as you
say the dv format stream of 25mb/s is only really around 3.8 mB/s
transfer, and the IEEE 1394 can transfer more data than that, right?
So theoretically transferring the uncompredded video off a dv camcorder over
1394 would only be around 5 x 3.8mB/s of data.
19 mB/s, 1394 should handle that amount, no? And then that would be the full
uncompressed video of about 125 mb/s.
I realize you meant the DV standard is 25 Mb/s so sure regular dv codec
wouldn't be used, naturally.

But i would think if someone modified the camcorder to bypass the dv
encoding in chip in camera and sent uncompressed video to computer thru 1394
cable, you would need to also modify the 1394 card to receive such a data
stream and not try to uncompress it or use the standar dvd codec to read the
data.

It sounds possible in theory but who would do all this modifying to chip
circuitry in camcorders?
It sounds more likely that a manufacture would just come out with a digital
camera that passes full video to PC using a special codec
since PC's are faster now and can handle more processing power now.

But the 5 to 1 compression of DV is excellent quality, I don't see it
happening. The Toaster handled full uncompressed video cause that was video
being captured from high quality analog cameras and they wanted to maintain
editing in uncompressed as long as possible. But that all changed with the
DV format so i don't think they'd go backwards to less compressed digital
format, although it might appeal to some Pros.

Thanks to everyone for correcting my math on bits and bytes. :)
That always confused me when carrying over to video data. :)
AnthonyR.

[Back to original message]