h264 playback and quality settings

[Smiff]

ok so the deblocking really helps low res h264 content, say 6xx X 3xx [removed] sources etc
however on high res content like iplayer 1500k, the you need all or almost all deblocking skipped to keep things smooth.

so the problem is if you view different types of content (which surely most do) you have to keep going into video settings and adjusting these dvdplayer options. this isn't practical for most users so you leave deblocking off, leading to poor quality on the low res sources.

possible solutions?

a) allow deblock to be set according to res
b) automatic dropping of quality settings e.g. a few seconds after loading each video, if cpu is 100%, drop one level, then another etc until smooth, probably quite complex to code this though!

not sure if advancedsettings.xml already offers anything like (a)? if so how about including it by default so everyone gets better looking / smoother video.

[professor_jonny]

possibly you could have 2 builds of xbmc installed on with all the sd content and one with the hd content ?

[spicemuseum]

ok so the deblocking really helps low res h264 content, say 6xx X 3xx [removed] sources etc
however on high res content like iplayer 1500k, the you need all or almost all deblocking skipped to keep things smooth.
...
automatic dropping of quality settings e.g. a few seconds after loading each video, if cpu is 100%, drop one level, then another etc until smooth

Adaptive de-blocking filter, I like it.

[Smiff]

possibly you could have 2 builds of xbmc installed on with all the sd content and one with the hd content ?

that defeats point of removing constant user settings changes.


adaptive deblocking.. nice name. yeah does any other GPL app have similar feature that could be "borrowed"?


seems nearly all content is h264 these days, bit unfortunate as it's so near xbox1 cpu limit, but that's that.

[BuZz]

seems nearly all content is h264 these days, bit unfortunate as it's so near xbox1 cpu limit, but that's that.

use a mediaserver and transcode ?

having said that, I am still able to find dvdrs and xvid encoded content.

[Smiff]

you can transcode live streams and plugin content? does this work well?

you can find xvid, but much of the content i look for now i'm lucky to find any working sources at all, never mind in particular res/codec.

what do you think of the automatic settings adjustment idea buzz?

[BuZz]

not for live streams no.

I think it's not all that feasable to have this done automatically. having it able to be controlled from a plugin is more feasable, or having a per video setting, but waaay down my todo list.

when frames get dropped currently btw, it already switches some settings to speed up the decoding so it can catch up. I might be able to improve this, but it could affect other videos as its not h264 specific. I suppose its not impossible to have some extra code for h264, but there is currently too much other stuff that needs attention.

[BuZz]

having a further think, it might be possible to look at bitrate/res and set the loop filter accordingly, but there are other options in h264 I believe that can affect this so it might not work that well.

[Smiff]

did you do anything to speed up h264 recently? just tried 31661 and think i see 5-10% lower CPU usage in TVcatchup than in 3.2
this is handy because that plugin really needs deblocking! cheers. might be placebo.

[BuZz]

nope. maybe tvcatchup changed something or some other setting ?

[Smiff]

ok i must have a settings mismatch, tried to get it set same but obviously not, please ignore.
actually it's still not usable with default settings, as it regularly drops to about 12fps.. for some silly reason TVC uses 1024x576 res for both medium and high quality settings.. :/

[Smiff]

not sure where to put this so dug this ol' thread up..

been playing with v3.3 today. this is quite exciting

i see massively improved ram usage with medium res h264 content (which is all i care about really).

iplayer 1500k streams (around 480 lines i forget exactly)
720p
xtv-saf skin
dvdplayer with fast mode enabled

xbox2 around 9MB free (3.2) -> 16MB free (3.3)
xbox1 around 12MB free (3.2) -> 20MB free (3.3)

so around 7MB/8MB more free RAM in 3.3 with all settings as best i can matched. it's possible the caches are different so these may be out a mb or 2.

this is really significant, it should mean lots less stuttering especially when entering and leaving fullscreen video, and the xbox playing lots more videos before it hangs (which it inevitably will eventually from some memory leak or whatever, i expect).
not sure if there's much difference in cpu %, not much change i think.

[bigkidoz]

I have noticed a definite improvement especially playing files off a flash drive, rarely get any buffering where previously it would buffer nearly every minute. This is mostly with MP4 h264 hd tv rips.

[captainsensation]

I have noticed a definite improvement especially playing files off a flash drive, rarely get any buffering where previously it would buffer nearly every minute. This is mostly with MP4 h264 hd tv rips.

same here. I was content with 3.3 beta 2 but then i tried youtube on 3.3 and it was seconds faster and more responsive. So much so that i deleted the beta for 3.3 yesterday. i was not expecting the speed improvements to be this significant.