On a sunny day (Tue, 22 May 2018 14:33:43 +0100) it happened Chris Elvidge
 wrote in :

>On 22/05/2018 14:14, Gareth's Downstairs Computer wrote:
>> On 22/05/2018 13:38, A. Dumas wrote:
>>> On 22/05/2018 14:06, Gareth's Downstairs Computer wrote:
>>>> A bit strange to have to purchase a per-RPi licence to
>>>> decode MPEG2; what's the thinking behind that?
>>>
>>> https://www.raspberrypi.org/blog/new-video-features/
>>
>> I see. Thanks.
>>
>> As it seems to be a software issue only, then it's up to us
>> to write our own decoders (for our own private use)
>>
>
>How much work can you realistically do for £2.40 per?

With that reasoning / attitude there would not be Linux.
The key (I have bought 2 for 2 raspis) seems to activate the HARDWARE mpeg2
decoder,
that gives you increased decoding speed = more fps in playback.
For the rest mplayer (based on ffmpeg AFAIK) already has most soft decoders,
sources available.
All done for free by a zillion people working on it, I personally added
some feature to ffplay.
ffmpeg wil happely re-code one format to the other,
and I think fixing an audio video delay is no issue,
I also have done that with my own code (time stamp).

I do not know why omxplayer is the only player supporting that hardware decode,
the rapi org club should really  provide drivers for mplayer and xine.
omxplayer is an irritating piece of shit written by somebody who cannot display
an other error message
than 'have a nice day' and then exit.
programmed by some idiot it seems.
It does play, but keys or not, I do not use raspies as mediaplayer (tried it).
My TV has an 1 GB harddisk connected to it, when needed I recode on the PC to
the right size and format with ffmpeg,
and put it on that disk.

You can probably hack the key but you are right: not worth the time.
;-)

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