Apple TV

[Christian Hewitt]

On 2 Nov 2010, at 00:11, Andy Bircumshaw wrote:

>> ... get_iplayer uses ffmpeg to move flash video into an mp4 container so it's not impossible to change the ffmpeg commands to include cropping that resets the video dimensions to what the crippled QuickTime player can handle. The negative to this approach is that you perform a full re-encoding of the video file. Instead of a quick 2 minute swap of container formats it can take an hour or more to re-encode longer shows. I did some experimentation before and cropping is what you need. I can't remember the exact commands though - I ran out of patience and moved on to other ideas ...
> 
> I'm not sure that cropping is required, as such. See also my other post, but in the comments on one of the pages of Phil's site, Andy (ctrl-f "apple") claims to have been able play other 1280×720 movies: 
>   http://linuxcentre.net/bbc-iplayer-hd-1280x720-now-supported-by-get_iplayer
> 
> He notes that iPlayer's HD recordings have 188Kbps audio and that Apple TV will play up to 160Kbps. That transcoding is cheap in processor cycles.

I understand audio but video is a language i'm still learning. Several people have told cum half-explained to me that the issue with the BBC streams since the changes in April is that the video is now streamed in dimensions outside the hard-coded limits of the ATVs non-standard QuickTime player; hence using an alternative media player works. It's not an issue with video codec's or the audio side of things.

At the time the streams changed I was told the solution is to use a player that understands how to bottom-crop the video to put things back to the right dimensions. I was pointed to reports of media player apps on desktop OS's handling the wrong dimensions by showing green lines at the bottom of the screen as evidence of a bottom-cropping problem. I still don't really understand it (or believe it) so I'm just regurgitating what others have said, but at the time I did run some experiments with ffmpeg to crop flashvhigh and flashhd content back to normal dimensions and it did result in video that displayed on the ATV "sort-of-okay" ..not smoothly or in great quality, but then I expect a range of other ffmpeg parameters need to be set to get a decent quality transcoding result.

In the end other experimenting found nitoTV (which includes mplayer) which worked fairly well, and since then XMBC which for me is a great solution and hopefully a bit more future-proof.

Christian