World Service podcast bit rates

RS richard22j at
Tue Aug 15 04:40:54 PDT 2017

This is off topic so if you are going to be offended please stop reading.

Vangelis mentioned at the weekend that the World Service is very popular 
overseas.  I don't doubt it.  It seems to have a very wide range of very 
informative programmes.  My problem is being selective.  At one time I used 
to use Juice to retrieve all the podcasts I might be interested in and found 
myself drowning in downloads I was never going to have time to listen to. 
That is not the reason for this post.

I noticed that some of the programmes mentioned in the discussion about w1, 
w3 and 15 digit PIDS were limited to dafmed, hafmed and hlsaacmed and a bit 
rate of 96kbit/s.  They also mostly had podcasts, and in the UK I was 
offered a choice of 128kbit/s and 64kbit/s.  I was aware that BBC radio 
outside the UK was at one time limited to 96kbit/s, but I did not know if 
that limit still applied.  It is difficult to find the answer on the BBC's 
web site.  I don't know either whether the 128kbit/s podcast option is 
offered outside the UK.

If it is, it seems a lot more attractive than 96kbit/s HE-AAC with the SBR 
extension from get_iplayer.  As Vangelis pointed out a few weeks ago, if 
HE-AAC with SBR is played on a player that does not support SBR half the 
bandwidth is lost.  I have been wondering how best to deal with that. 
Converting to MP3 seems a possibility, despite the purists' objection that 
it is converting from one lossy format to another.  It seems ffmpeg does not 
support SBR, but VLC could be used for the conversion.  The podcast is 
already available as MP3.

Even if 128kbit/s is not offered for podcasts outside the UK, 64kbit/s MP3 
is probably better than 96kbit/s HE-AAC with half the bandwidth missing.

There is something else surprising I noticed this morning about the latest 
episode of Science in Action, p05bdb8p.  The original version was limited to 
96kbit/s with dafmed, hafmed and hlsaacmed.  The podcast version, p05c1hf1, 
not only had dafstd, hafstd and hlsaacstd at 128kbit/s, but also dafhigh and 
hafhigh at 320kbit/s.

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