Preparing for latest update - modes questions.

[Budge]

Hi and many thanks,

On 05/02/17 22:55, SquarePenguin wrote:
> On 05/02/17 18:35, Budge wrote:
>> Having read the Release Notes for 2.98 my understanding is that this is
>> the default tv mode and it will use dash dvf as first choice and hls if
>> dash not available and so forth degrading according to availability, so
>> no tvmode setting is needed to achieve my objectives.
>
> Release notes says:
>
> For each video size, hvf streams are used in preference to dvf streams
> for the present, but dvf will likely become the preferred format in a
> future release, so it is in your interest to test it (use --tvmode=dvf).
>
> So it won't use dvf (MPEG-DASH) as first pick, it'll use the hvf (HLS
> (Apple HTTP Live Streaming)) by default.
>
> There are other considerations to enabling dvf so read that section of
> the release notes again to be sure you're happy:
>
> https://github.com/get-iplayer/get_iplayer/wiki/release298#4-dash-tv-support
>
>> If this is correct please could somebody confirm and I shall remove all
>> reference to tvmode from my prefs.
>
> The above not withstanding, yes you are correct and can just use the
> default without specifying to achieve the result you want.
>
>> For radio downloads I want the best resolution available for music and
>> opera and believe the radio 3 default of 320kbps would be the right choice.
>
> I'm unsure what you mean exactly by the 'radio 3 default' part but the
> default radio mode cascades down through:
>
> dafhigh,hafhigh,dafstd,hafstd,dafmed,hafmed,daflow,haflow
>
> and dafhigh = 320kbps AAC so you should get that as default and then
> lower if that's not available.
>
>> For spoken word such as book readings and drama, however, I do not need
>> this resolution and believe 96kbps would be more than sufficient.
>>
>> Most of my radio downloads are done by pvr as a nightly cron job.   What
>> I am thinking therefore is that I should set my default radio mode in my
>> prefs and then qualify it (degrade it,) when for a spoken word programme
>> by including an appropriate  --radiomode in each relevant pvr job.
>
> This sounds like a good way to go if the bulk of what you want is
> non-spoken, that way you'll have to do the minimum amount of specifying
> lower quality modes for the spoken stuff.
>
>> Modesref gives me --radiomode
>> default=dafhigh,hafhigh,dafstd,hafstd,hlsaacstd,dafmed,hafmed,daflow,haflow,hlsaaclow).
>>
>>
>> I understand this to mean that if the pvr job is type=radio and I do not
>> specify a radiomode I get the default as above.  What should I put if I
>> wish to downgrade the radio in the pvr job to 96kbps but not have
>> download fail if that mode is not available.  Sorry to be so dumb and
>> grateful for all guidance given.
>
> Correct and you can actually use the 'radiogood' shortcut to cascade
> down through:
>
> dafmed,hafmed,daflow,haflow
>
> and dafmed/hafmed = 96kbps so you can specify '--radiomode=radiogood'
> for those spoken word downloads get_iplayer will do the rest.
>
> Hope that helps!

It does indeed.  Exactly what I was hoping and thankyou for clarifying 
the syntax.  I would never have got "radiogood."

I read and promptly forgot the sentence about dvf not being the default 
for the time being as I was intending to try dvf.  One question that 
does arise is that if I do use --tvmode=dvf it seems there is no cascade 
from there if that mode is not available.

I don't understand the statement:-
"The audio and video for dvf streams must be downloaded separately 
(files have .raw.m4a and .raw.m4v extensions)."

I assume this only matters if I elect to keep the raw data files and 
that ffmpeg sorts out the muxing of both streams if I just accept .mp4.

Thanks again.  Will report progress in due course.
Budge