[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-video
Subject:    Re: [video4linux] streaming capture
From:       Dirk Vangestel <dirk () specs ! philips ! com>
Date:       1998-07-29 8:03:12
[Download RAW message or body]

At 21:38 28/07/98 -0700, Bill Dirks wrote:
>Alex Bakaev wrote:
>> Bill Dirks wrote:
>> > 3. I also wanted to have buffer attribute flags. I want to have the
>> > flexibility of asking for buffer types because hardware could have
>> > special memory on board, or semantics or something.
>> 
>> How do you use this special memory ?
>
>I just want something that's extensible. I imagine video compressing or
>video processing cards could have all kinds of mappable memory on them.
>I hope I'm laying down a foundation that can be built upon by many
>future devices.

Not all video capture cards consist purely of hardware processing where
you don't have to do anything other than programming some hardware
registers and pass some buffers (ok, maybe that's a bit too simplistic :)
Imagine putting a programmable chip on a card, and some memory where you
can download executables to. Part of the memory could be used to run the
program, part could be used for internal buffer management (used for
capturing/filtering/compression/whetever). Suppose you have enough
memory available to do _all_ buffer management on the card itself,
meaning the main memory never even gets to see the captured image
(there's no need really: previewing can be done directly to the
video card, and saving to disk can be done directly to disk. Or
network card for that matter).
Would that be good enough to be called 'special memory'?
There might not be many cards available using this principle
(well, there's at least one ;-) but I think you'll see more of them
in the future.

------------
To unsubscribe from this list send mail to majordomo@phunk.org with the
line "unsubscribe video4linux" without the quotes in the body of the
message.

[prev in list] [next in list] [prev in thread] [next in thread]