Why mp4 or mp4.ts from identical installation?

[RS]

>From: Charles Bradshaw
>Sent: Friday, February 10, 2017 10:05 PM

>>> I did, sort of, say which version of get_iplayer I'm using. If you
>>> looked at dumps.txt.zip in my original post the last lines both say:
>>> "get_iplayer Web PVR Manager v2.97, ©2009-2010 Phil Lewis - Licensed
>>> under GPLv3".
>>> ...
>>> I think you might eventualy understand the problem if I tell you that
>>> with get_iplayer v2.98 the problem goes away completely. Then both
>>> installs, but still using original package manager installed with
>>> different versions of ffmpeg, produce identical .mpg files. Albeit ~1.4
>>> times the size than when the intermediate is flash.
>>>
>>> I'm very happy that the problem has gone away, but suggest that
>>> somebody, hopefully with a better understanding of the internals than
>>> me, will find themselves revisiting what must be a subtle bug. :-(

I am glad your problem has gone away with v2.98.  You have not said which 
mode you are using, which probably means you are using the default.  If that 
is the case, you are not comparing like with like between v2.97 and v2.98.

In v2.97 the default is HVFsd, 960x540 50fps, with a bit rate of 2787kbit/s.
In v2.98 the default is HLShd, 1280x720 25fps, with a bit rate of 
2379kbit/s.
Flashhd was 1280x720 25fps, with a bit rate of 2400kbit/s.
That is the reason for the difference in file sizes.  It is not a bug. 
There is now an internal decoder for HLS and HVF.  Neither uses RTMP.

As for whether the ffmpeg version was a red herring, your original complaint 
was that ffmpeg would not multiplex the .mp4.ts file to .mp4 in one of your 
installations.  That installation was using ffmpeg v2.3 when v2.5 or above 
was required.  If you read the release notes for v2.98 you will see that for 
the new DVF mode, if you decide to try it, you will need v3.0 or above of 
ffmpeg.