2013-01-24, 20:41
(2013-01-23, 20:25)PobjoySpecial Wrote: I'm pretty sure 1080i requires a higher bandwidth than 720p (i.e. more pixels per frame). The Pi is capable of normally playing back 720p and 1080i files, so it seems strange that it would stutter on live streams. What codec do the streams use?
Have you tried a different, lightweight back-end (e.g. TVHeadend) to isolate the problem? If the problem doesn't go away, then maybe the Pi truly is at fault. I think many would like to know more about the Pi's limitations before trying setting up PVR.
As I understand it, 1080i is interlaced so that it alternates between sending even and odd rows in each frame. Therefore, only 540 lines are sent each frame but it is so fast that the illusion of 1080 lines is there. Whereas 720p sends 720 rows in every frame (better for sports with fast motion). This would make 720p more heavy to render than 1080i.
I also confirmed that all my channels use dolby digital (even 720p) so it's not decoding DTS audio. My next step would be to try a different back-end, although MediaPortal works fine to my main HTPC.
