[Kdenlive-devel] capturing

[Edwin Schepers]

On Monday 22 March 2004 09:12 am, Rolf Dubitzky wrote:
> On Sunday 21 March 2004 22:05, Edwin Schepers wrote:
> > I have a digital camera. I'll have a look at pgrab. I don't have any
> > knowledge (outside some kde programming), but that will only take time
> > (well, only... :-)
> > I never grabbed with Linux, but I'll get it working.
> > Then I could start making a gui in kdenlive.
> 
> That sound very good. I don't know how much you know about kdenlive/piave, 
but 
> you probably have already understood, that kdenlive is the GUI part which 
> depends _only_ on KDE/Qt and piave is the render engine which has all kinds 
> of nasty dependencies on the file, audio, and video formats, audio systems, 
> video systems and ieee1394 interface. The two components comunicate via a 
> pretty simple protocol over sockets. This protocol needs to be extended to 
> handle all that is necessary for capturing (which is trivial). I am _very_ 
> interested in cpturing capabilties, so if you are really interested, I can 
> implement all the necessary changes in piave and code all the communication 
> to the actual hardware (most of this is already done anyway). 
> So if you start creating a GUI component in kdenlive, all you need to do is 
> send commands via the (existing) communication channel to piave. You don't 
> need to bother with the underlying hardware. (In fact, you must not, since 
> kdenlive should be independent of hardware dependencies)
> 
> So the first command to send would probably be something like
> 
> <captureGetDevices>
> 
> to see what is actually attched to the PC. piave would answer something like 
> the following (run "pgrab -v 2" to see if/how your cam is reported)
> 
> <captureDevices>
>     <ohci1394>
>         <device devid="0" name="Sony DCR-TRV30E" type="AVC (subtype=VCR)" />
>     </ohci1394>
> </captureDevices>
> 
>  The device id is an integer for further reference of the device. The name 
is 
> actually read from the device itself and can be displayed to the user. In 
> case more than one device is attached, you can offer a selection box or 
> whatever. 
>  Then kdenlive could then send commands like
> 
> <capturePlay devid="0">
> 
> and
> 
> <captureRecord devid="0">
> <captureStop devid="0">
> .
> .
> .
> 
> 
> I havn't really thought it through, that's just what comes from thetop of my 
> head. Shouldn't be too dificult to come up with a reasonable syntax and set 
> of commands. 
Hi Rolf,
Do you already have something useful on this item, so I can start making a gui 
and do some testing ?

Regards,
Edwin