Video Streaming Input/Decoder to jit.qt.movie

Paul Yuen's icon

Hi,

I would like to find out if video streaming input/decoder is on the wish-list for next Jitter release?

It would be great if it is, but if it is not, is it possible to write an external object that does it?

Any insight will be of great help. Thanks.

Cheers,
Paul

Jeremy's icon

jit.qt.movie is already capable of reading http and rtsp QuickTime
streams. What other kinds of streams are you thinking of?

jb

Paul Yuen's icon

Hi JB,

Thanks for your reply. It's good news, because I wasn't able to find rtsp support as input from the jit.qt.movie reference. At present, could jit.qt.movie take in rtstp 3gp streams directly, e.g. mpeg4 video + amr-nb audio, mpeg 4 + acc audio, etc.?

Somehow I thought amr-nb and acc audio formats are not supported in current version. If they are not supported, does that mean I need to somehow decode the audio formats to a streaming format that MAX/MSP can take in?

Thank again.

Paul

Jeremy's icon

Jitter should be capable of streaming any QuickTime-compatible rtsp
source. If QuickTime Player handles it, and Jitter doesn't, I'd like to
know about it.

jb

Paul Yuen's icon

Hi,

Also, I have tried reading a 3gp video file (with probably amr-nb audio), and split the audio out via spigot~.

But when I read the video file, it throws the following error message:

"error: jit.qt.movie: error -205 setting media soc"

So I assume it's a format issue. Maybe I misinterpret the error code...

Thanks.

Paul

Paul Yuen's icon

Hi,

Sorry I take in what I posted earlier. It seems AMR-NB is supported perfectly fine. Maybe the error is due to another cause.

Cheers,
Paul

Jeremy's icon

Yes, you are interpreting the error code.

a) I don't believe that spigot~ works with streams

b) spigot~ is presently broken under QuickTime 7, as has been
exhaustively discussed on this list. We're in the process of developing
a workaround. The workaround defintely won't work with streams. Please
file complaints with: Steve Jobs, 1 Infinite Loop, Cupertino, CA 95014

jb

Paul Yuen's icon

JB,

Thanks a lot for the clarification. I will search for postings on spigot~.

One more question: Is there any workaround if I'd like to process the video streams and export the processed video stream together with the original video stream as a quicktime movie file?

Currently, I understand how to copy an existing audio file as a track to jit.qt.movie, but don't know how to do that with an audio stream. Would that be possible?

Thanks!!

Paul

Paul Yuen's icon

Sorry typo:

export the processed video stream together with the original AUDIO stream as a quicktime movie file...

P.S. And Yes, I will write to 1 Infinite Loop... haha

Jeremy's icon

No way that I'm aware of. Streamed audio is typically "untouchable",
although you could try exporting/flattening a streaming movie and see
what happens. We don't stop you from trying it, although you might run
into some errors.

jb

Paul Yuen's icon

Thanks for the insight, JB. I will try and see what will happen.

Have a nice day~

Paul

dan's icon

Could you expand on this untouchableness, Jeremy? I'm after the same
thing: reading in audio and video from an RTSP stream and writing to a
buffer or a file (or multiple buffers and files if necessary).

thanks,
dan

Jeremy's icon

I mean that there's no way, in QuickTime, to get at the sample data for
this stream. Possibly one could write an Audio Unit for intercepting the
data and doing something with it, but I don't believe that streamed
audio uses the same audio pathways as disk-based audio. I haven't done
any real research on the topic, though.

jb