[FFmpeg-devel] 24x7 recording of M4A audio

[Jörg Beckmann]

Hi Steven,

I assume the cause is similar to the M4A problem. MPEG DASH uses many tables to hold things together and the contained M4A stream provides even more. Therefore I don't think it's a bug. Some times ago I had some URLs, but they are all dead meanwhile. But I found this one: 

http://rdmedia.bbc.co.uk/dash/ondemand/testcard/1/client_manifest-audio.mpd 

It's not a live stream, but it contains 1 hour of audio. If you copy it with 

ffmpeg -i http://rdmedia.bbc.co.uk/dash/ondemand/testcard/1/client_manifest-audio.mpd -c:a copy stream.m4a

you can see that the memory usage increases up to about 8.8 MB (on Windows 10) until the stream ends.

Jörg


> 在 2019年10月21日，下午3:50，Jörg Beckmann <Joerg.Beckmann at scisys.com> 写道：
> 
> Hi all,
> 
> I've written an application to record audio streams continuously for broadcasters using the FFmpeg libraries. For most stream types it's working without any problems. One major exception are M4A encoded audio streams, received from a professional DAB+ receiver. Because of the tables included in the stream, the used memory of the process increases without any limits until the process crashes. I know, it's not a bug, it's a feature, but this feature kills my recorder every few days. My plan is to add an option to the decoder in mov.c to ignore all tables included in the stream. I would like to send my changes as a patch to this mailing list. Would you incorporate such a patch into the source tree? Of course, the default behavior of the decoder should not change at all and I already read the description of the acceptance process for patches.
> 
> One of our customers asked to record audio from MPEG DASH streams. My tests have shown even stronger increasing memory usage for those streams. I didn't look into the sources for MPEG DASH decoding yet, but it might be the next candidate to add an option to ignore the tables.
Hi Jorg,

	Can you leave the dash link here, I want check about that, and try to fix it.


Thanks
Steven