Preparing for latest update - modes questions.

[SquarePenguin]

On 05/02/17 21:19, RS wrote:
> I would discourage anyone from using the best, better ... mode names,
> because their meaning has been changed between versions. This is not
> something you are proposing to do, but a number of contributors to this
> listserver seem to have been confused by it

Those 'modes' are not modes, they're shortcuts and by design it is
expected to change which specific modes these shortcuts triage. These
shortcuts respond to the changing quality/size streams iPlayer delivers
and changes are announced in the release notes so this is expected
behaviour.

> Now it seems in v2.98 DASH modes have become DAF.

The reasons for this are outlined in the release notes for v2.98.
Essentially it's because there is now MPEG-DASH available for TV which
necessitated a name change for 'dash' to 'daf' (DASH Audio Factory) for
radio and to the new 'dvf' (DASH Video Factory) for TV. It simply
introduces a distinction between the TV and radio modes.

Remember again that even these daf/dvf 'modes' (and indeed all modes)
themselves are also shortcuts to specific stream types (as outlined in
the Stream Types table) and video sizes/audio bit rates (outlined fully
in the respective TV/Radio modes tables).

So, whilst the 'dash' shortcut has now changed to 'daf' for radio, the
same underlying stream type and bit rate is being used.

Indeed, if you try to use the old names, they'll simply be remapped to
the new ones and a warning displayed which should bring this new
behaviour to light, but you'll get the same file you would have before.

> HLS radio modes changed to HAF modes between v2.95 and
> 2.97.

And the reason why are outlined in the 2.96 release notes, but it's
basically the same as above.

It may be you're just voicing your displeasure at these changes and not
seeking answers as to why they occurred, so apologies if I've misread
your intent/question.

> As for tv modes you can't even change them reliably at the moment
> because there are contradictions in the Wiki.
> https://github.com/get-iplayer/get_iplayer/wiki/modesref
> It seems some DVF modes have been introduced, but they do not appear in
> the TV Modes table with the detailed descriptions of the modes.

Check the Wiki again, the details are now there, though the Stream
Format is stated as HLS, when I would have thought it should be
MPEG-DASH. Maybe a typo.