Issues with Large Files

[RS]

>From: Budge Sent: Thursday, January 12, 2017 18:26

>Many thanks.  Yes I agree ffmpeg was my first thought but I am spoiled for 
>choice of command options.  ffprobe output didn't tell me what I was 
>looking for although that may be due to me not understanding what I was 
>looking at.  However I have no doubt ffmpeg will clean things up.  I shall 
>try a few options and see what happens.

Thanks for drawing attention to this.  I did hope something similar might 
lead to a solution of the problem I have playing DASH/M4A/AAC files on my 
AGPtEK A02.  I found about a year ago that ffmpeg created files with Major 
Brand M4A and Minor Version 512, which the AGPtEK player  did not seem to 
like.  I used
mp4box  <file>.m4a -brand M4A:0 -out <file1>.m4a
from https://gpac.wp.mines-telecom.fr/mp4box/mp4box-documentation/
to change the Minor Version to 0.  I then found I could play the files, but 
only if they were shorter than 14min at 128kbit/s.

Following your post I have looked at it again.  I see that by default 
mp4box -brand M4A introduces interleaving of 500ms.  I tried
mp4box  <file>.m4a -brand M4A:0 -inter 1000 -out <file1>.m4a
to give 1s interleaving and that allowed a 24min file to be played, but the 
display showed Format error after 15min.  I also tried -inter 2000 for 2s 
interleaving.  That again allowed a 24min file to be played but with a 
Format error after 5min.

mp4box <file> -info
gives a bit more information than ffprobe and ffmpeg.  GPAC refers to 
segments, fragments and interleaving.  I am not sure how these relate to 
what Linn calls chunks.

I have tried running ffmpeg with -acodec copy and with -acodec aac, but that 
does not seem to help.

artisticforge said Handbrake fixed his files.  Handbrake will not convert 
audio only files.  I have seen a workaraound to add dummy video, but that 
seemed a bit cumbersome.  I'll have to give it a try.