[theora] Theora Intra (ptalarbvorm) vs. MJPEG

[Basil Mohamed Gohar]

On 05/12/2010 02:40 PM, Andrey Filippov wrote:
>
>
>     However, and this is just an honest question on my part, how easy will
>     it be for a consumer to work with the resulting video?  The
>     advantage of
>     using Theora Intra is that it is still fully-compliant Theora
>     video, so
>     anything that claims to support Theora video should be able to play it
>     without modification.  If efficiency were the sole concern, and not
>     ease-of-use with resulting video, then we'd have a lot more options
>     available to us as to where we can go.
>
>
> Yes, I see your point. But our experience shows that with CPU power of
> the regular computers go up it makes sense to do post-processing on a
> host PC, color conversion/interpolation in the camera is even more
> lossy than the JPEG compression itself. Additionally most video has to
> be processed/edited anyway, so combining these steps really make sense
> for me.
I see a lot of sense in these assertions.  However, what pops-up to me
for a regular user is that it's an additional step they have to take,
and most tools don't already feature this capability.  It seems that, if
we incorporate such a codec into the resulting product, then we will
have to also have software ready for the consumer to use to do the
post-processing.
>  
>
>
>     So, having said that, what do you think we can do at this point?
>      Maybe
>     you can explain a bit more about the processing of the JP4 video
>     that is
>     produced by your products?  For example, I downloaded and watched some
>     of those JP4 videos, and, of course, they were not in a final
>     form, but
>     I also did not know what to do next with them.  Can you give us some
>     idea about the chain of processing them after they've been
>     captured?  Is
>     there a way to make this as transparent as possible for end-users?  I
>     love that we can discuss this idea further.
>
>
> Did you get to the http://community.elphel.com/jp4/jp4demo.php ?
> There is also ImageJ plugin for processing JP46 files (JP46 can be
> opened as regular JPEGs, then the pixels are rearranged, JP46 has to
> use modified libjpeg or similar)
I'm looking at the page now.  It's very interesting...
>
> So far most JP46 images were used for still images (with Elphel model
> 323 and 353 cameras) but now we at least some solutions for the video
> and continue to work in this direction. And there could be
> alternatives to literal JP4 implementation
I did see some video samples of the JP46 video, but I don't think I saw
the resulting demosaiced video.
>
>
>     And to bring up the point, as Theora does show superiority to
>     capturing
>     details over JPEG, then adapting the JP4 format to use Theora's intra
>     coding as the codec also seems like a win too.
>
>
> Yes, it may be good at that too, what I was telling is that video
> recording needs some dedicated processing/compression, moldified for
> the different (from the video distribution) goals.
It would be great if we had some raw Bayer video footage.  I don't have
any right now...can anyone point us to some?  It would also be nice if
JP46 was available as an actual codec to use for "compressing" the raw
Bayer video as well.  Supposedly my webcam (Logitech Webcam C600) has
the ability to send raw Bayer pixel data, but I don't know in what
format that is.