[vtkusers] vtkVideoSource

[Simon Drouin]

David Gobbi wrote:

>Hi Simon,
>
>I can't comment on observing the "Modified" event because I've never
>tried doing that with vtkVideoSource.  In fact, the vtkMILVideoSource
>(the one that I used the most) does Modified() calls from a separate
>thread, and triggering an Update from any thread other than the main
>thread would probably cause things to break horribly.
>
>However, with regards to separating the video source from the frame
>buffer, I wrote a couple classes to do precisely that but I didn't
>finish integrating them before I my PhD was completed.  If you're
>interested in finishing the job, I can send these classes along to you.
>
>Cheers,
> - David
>
>On Wed, 8 Dec 2004, Simon Drouin wrote:
>
>  
>
>>Hi,
>>
>>I'm using vtkVideoSource in a program.  I 'm watching the "Modified"
>>event. When it is trigered, I call Update. The windows that display
>>video are all watching the "Modified" event of the vtkVideoSource output
>>(vtkImageData) so that when Update is called, they should be notified
>>and get the chance to render.
>>
>>My problem is that the Update function of vtkVideoSource eventually
>>sends a Modified event too and since my function that watches the
>>"Modified" event calls Update, I end up with and infinite loop.
>>
>>I would like to add an event that is more specific that "Modified" and
>>that is triggered when something in the framebuffer has changed. This
>>event should be called when a new frame is grabbed, when the framebuffer
>>index is changed and when the framebuffer is updated.
>>
>>So here's my questions:
>>
>>How should I add this event? Should I use an already existing event type
>>(which one?) or create a new one?
>>
>>How do I submit my code?
>>
>>
>>btw, I just finished coding vtkV4L2VideoSource (Video for Linux 2 video
>>source). I will eventually like to submit that too.
>>
>>Also, am I the only vtkVideoSource user that feels the video source and
>>the frame buffer its using should be in 2 different classes.
>>
>>Thanks in advance for your help.
>>
>>Simon Drouin
>>_______________________________________________
>>This is the private VTK discussion list.
>>Please keep messages on-topic. Check the FAQ at: http://www.vtk.org/Wiki/VTK_FAQ
>>Follow this link to subscribe/unsubscribe:
>>http://www.vtk.org/mailman/listinfo/vtkusers
>>
>>    
>>
>
>_______________________________________________
>This is the private VTK discussion list. 
>Please keep messages on-topic. Check the FAQ at: http://www.vtk.org/Wiki/VTK_FAQ
>Follow this link to subscribe/unsubscribe:
>http://www.vtk.org/mailman/listinfo/vtkusers
>
>  
>
Hi David,

I would be very happy to have your code of separate video source and 
buffer. I should have time to work on that soon. I would like to create 
an alternate type of buffer that can store images on disk instead of 
keeping everything in memory.

Simon