[streaming] Re: Streaming mp4+AAC to mobile phones

[PERET Pierre-Hugues]

>one more guess:
>1) is vlc able to successfully encode amr_wb to a file (instead of 
>streaming) ?
>2) if so, can QTPlayer (or any other player) play this file ?

amr_nb and amr_wb transcoded file with vlc are playable locally with 
realplayer : AMR_NB works nicely, AMR_WB doesn't play nicely (very noisy 
and weird sound).

>3) if so, then my guess is that vlc does not properly apply the amr_wb 
>(sawb) encoded content to the rtp stream. That was the reason for amr_nb 
>(samr) not working when I tried it about 4 months ago. VLC Developers told 
>me that the packetize_amr (in 
><https://trac.videolan.org/vlc/file/trunk/modules/stream_out/rtp.c>https://trac.videolan.org/vlc/file/trunk/modules/stream_out/rtp.c) 
>function does not work properly. It is described in RFC3267 
>(<http://www.apps.ietf.org/rfc/rfc3267.html#sec-4>http://www.apps.ietf.org/rfc/rfc3267.html#sec-4) 
>how to implement it. That's where I gave up...

The packetize methods used for amr_nb and amr_wb are the same (call to the 
same function packetize_amr() ).
I will have a look if a cannot make aac working.

>Maybe some VLC developer can help implement the amr packetizer for rtp?
>
>
>>At 11:55 12/12/2005 +0100, you wrote:
>>>I came to the same conclusion as you .
>>>For now, i'm working on the sdp stuff which i think is the problem. Or 
>>>it might be the reflector module of DSS (in this case i doubt i could do 
>>>anything for it).
>>>
>>>At 17:02 11/12/2005 -0800, Torben Knerr wrote:
>>>
>>>
>>>>On 12/11/05, PERET Pierre-Hugues 
>>>><<mailto:ph.peret at free.fr>ph.peret at free.fr> wrote:
>>>>>Didn't tried with ffmpeg's amr_wb.
>>>>>trying with http allways make my operator says wrong url, putting the 
>>>>>full path or not.
>>>>>
>>>>>I talked on irc with some guys, and it seems that it's not very 
>>>>>possible to do what i want , and someone oriented me to helix mobile 
>>>>>server and mobile encoder, but it's far too expensive....
>>>>>
>>>>>as i want to take an already running stream and transcode it to 3gp , 
>>>>>i think i cannot do that with opensource or free software.
>>>>
>>>>I think it is possible with vlc+dss, as soon as the sound issue is 
>>>>solved. Even though the stream might not be 100% 3gp spec compliant, it 
>>>>worked (at least with video only).
>>>>
>>>>>I noticed that DSS is not able to stream mp4+aac to mobile phone -> 
>>>>>nokia 6630 , sound is not working, even with the sample which comes 
>>>>>with the server. Making aac streaming working on the mobile would be 
>>>>>the solution.(amr is not my preference).
>>>>
>>>>I think that's not possible with the 6630, because it can not play aac 
>>>>streams :(
>>>>On the other hand DSS _is able_ to stream mp4+aac (as you can see the 
>>>>stream with different players, such as QT), so imho it is definitely 
>>>>the mobile, which is _not able_ to play rtsp-streamed aac.
>>>>But you are right, amr_nb is no solution because it is too crappy... 
>>>>amr_wb might be okay, even though not as good as aac.
>>>>
>>>>>if you know a streaming server that can do that.. pls tell me.
>>>>>maybe tomorrow i will try amr_wb . i will keep you informed.
>>>>>
>>>>>NB : 3gp or mp4 generated by vlc doesn't play on the mobile phone on 
>>>>>local playback (possibly beacause of the lack of hinted tracks)
>>>>
>>>>Right, for local playback you need to hint the files. I used mp4box for 
>>>>hinting and got it work to play locally with mp4+aac and mp4+amr (both 
>>>>encoded with vlc). Don't remember if it worked with h263 video too, but 
>>>>i guess so.
>>>>
>>>>Good luck with the amr_wb stuff!
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