Adding custom codecs to gst-dsp

[P Leyshon]

Hi,

Quick question about gst-dsp.

If I wanted to design and add a custom DSP audio processor element to
gst-dsp, what would be the best way to do so?

Would I build the audio processor as an IUniversal API algorithm and
extend gst-dsp to accommodate?

For example , gst-element-dspaudio

Sink pad (up to 8ch raw audio) -->> DSP and perform some processing on
each channel -->> back to the arm where each audio channel has its own
source pad.

Secondly, would it be possible to make a gstreamer bin that operates
within the dsp? Such that we can create several dsp elements and move
them around within the bin and are processed on the dsp?

Look forward to hearing your ideas/comments.

Peter.

[Víctor M. Jáquez L.]

On Fri, Feb 10, 2012 at 04:19:52AM -0800, P Leyshon wrote:
> Hi,
>
> Quick question about gst-dsp.
>
> If I wanted to design and add a custom DSP audio processor element to
> gst-dsp, what would be the best way to do so?
>
> Would I build the audio processor as an IUniversal API algorithm and
> extend gst-dsp to accommodate?
>
> For example , gst-element-dspaudio
>
> Sink pad (up to 8ch raw audio) -->> DSP and perform some processing on
> each channel -->> back to the arm where each audio channel has its own
> source pad.

I've never seen that configuration, normally all the channels goes through a
single pad. In that case you will need and extra element to mix the channels
and deliver a single stream to the audiosink.

>
> Secondly, would it be possible to make a gstreamer bin that operates
> within the dsp? Such that we can create several dsp elements and move
> them around within the bin and are processed on the dsp?

Of course it is possible. With playbin2 I play videos where audio and video is
decoded by the dsp. The dsp is multitask.

vmjl

[P Leyshon]

Thanks Victor.

My task this week is to develop a proof of concept based on the
following block diagram
http://www.lucidchart.com/publicSegments/view/4f381026-baf8-4227-8078-5f710a405da7

Is this possible with gst-dsp as it stands?

I'll be forking gst-dsp at github.com/sgpu if anyone wants to follow
my progress.

Peter.

[Felipe Contreras]

On Sun, Feb 12, 2012 at 11:11 PM, P Leyshon <leysh...@gmail.com> wrote:
> Thanks Victor.
>
> My task this week is to develop a proof of concept based on the
> following block diagram
> http://www.lucidchart.com/publicSegments/view/4f381026-baf8-4227-8078-5f710a405da7
>
> Is this possible with gst-dsp as it stands?

Well, everything is possible :)

So far usn, dfgm, and the custom dummy protocols work, so I don't see
why not iUniversal (although I don't know much of this one).

I think it's good that you base it on dspdummy, as gstdspbase.c is
quite bloated and should be simplified a lot.

Maybe you can start with a simple one-in-one-out socket-node, like
dspdummy, and contribute the code back to gst-dsp, that would at least
proof that iUniversal works and might help you with further tests. At
the same time you can write a simple GStreamer element that doesn't
communicate with the DSP but generate output for 8 pads. People on the
gst-devel mailing list might be able to review that code and make
suggestions. Then it would be a matter of merging the two.

Cheers.

--
Felipe Contreras

[ozka...@gmail.com]

Hi,

We're trying to develop a custom video codec and currently running by using DSP on BB-xM. We'd like to add the new codec into gst-dsp in order to access it more easily  via gstreamer at the application layer. Unfortunately, I haven't find a kind of guidance or reference about the required interface from the codec and how to add a custom video codec into gst-dsp. 

Your replies will be greatly appreciated. Thanks in advance.

Regards,

Ozkan.

[Felipe Contreras]

On Wed, Nov 20, 2013 at 11:46 AM, <ozka...@gmail.com> wrote:
> Hi,
>
> We're trying to develop a custom video codec and currently running by using
> DSP on BB-xM. We'd like to add the new codec into gst-dsp in order to access
> it more easily via gstreamer at the application layer. Unfortunately, I
> haven't find a kind of guidance or reference about the required interface
> from the codec and how to add a custom video codec into gst-dsp.
>
> Your replies will be greatly appreciated. Thanks in advance.

Are you using usn.dll64P or some other custom interface? If the
former, most of the code in gst-dsp deals with usn (e.g.
gstdspvdec.c), if the later you might need to do more work, but it's
doable (check gstdspdummy.c).

--
Felipe Contreras