[Rabomil]

hi everybody,

i've been doing some testing with the x264 encoder (use ffdshow to decode it). to my surprise it is not as demanding as nero digital avc.

it is possible to use the important options like cabac, deblocking and b-frames, combined with a reasonable video resolution of 640x272 (aspect ratio = 2.36:1).  

i've posted a one minute sample, which you can find here.

please tell me whether you're able to play it without frame drops and tell me what you think of the video quality.


****************************************************************
movie name: the mexican (2001)
imdb: http://www.imdb.com/title/tt0236493/
movie length: 1h58m
source: r2 pal dvd

codec: x264 core 40 svn-375m, build nov 25 2005 by sharktooth
audio: dolby digital 5.1 (english)
video resolution: 640x272 (square pixel, 2.36:1 aspect ratio)
file size: 1480 mb (1/3 part of a sl-dvdr)
subtitles: dutch (vobsub)


encoder settings:
****************************************************************
-=bitrate=-

average bitrate of 1291 kbit (2 passes)

****************************************************************
-=rate control=-

bitrate:
keyframe boost (%) = 40
b-frames reduction (%) = 30
bitrate variability (%) = 30

quantization limits:
min qp = 10
max gp = 51
max qp step = 4

scene cuts:
scene cut threshold = 40
min idr-frame interval = 20
max idr-frame interval = 250
direct mode = temporal

****************************************************************
-=mbs & frames=-

other:
8x8 transform = no
max ref. frames = 1
mixed refs = no

partitions:
8x16, 16x8 and 8x8 p-frame search = yes
8x16, 16x8 and 8x8 b-frame search = yes
4x8, 8x4 and 4x4 p-frame search = yes
8x8 intra search = yes
4x4 intra search = yes

b-frames:
use as references = yes
adaptive = yes
weighted biprediction = yes
max consecutive = 3
bias = 0

****************************************************************
-=more=-

motion estimation:
partition decision = 5 (high quality)
method = hexagonal search
range = 16
chroma me = yes

misc. options:
sample ar = 1:1
threads = 1
log level = error
fourcc = h264

cabac = yes
deblocking filter = yes
strenght = 0
threshold = 0

****************************************************************
important info for xbox users:

this x264 (h264/avc) movie was encoded with xbox users in mind, so i did not use all encoding tools. this movie can be played without framedrops with xbmc, using a recent build of xbmc (3rd of august 2005 or newer), which is avc/h.264 compatible.

the cache settings are really important to play avc files without problems. these are the settings i use. but it is important to know that i'm only playing movies from dvd or harddisk. i adjusted my cache settings according to that.

video/audio/dvd cache - harddisk 4096 kb
video cache - dvdrom  7168 kb
audio cache - dvdrom 256 kb
dvd cache - dvdrom 4096 kb

all other parameters 0 kb

****************************************************************

[Kichigai]

i don't mean to sound like a n00b, but what about x264 (not nero avc/h.264, or even apple h.264) support? ffmpeg is using their own decoder, but is there some way that we could could use the same x264 decoder used in vlc (after all, they did develop x264, their decoder might be compatible)?

i'm only concerned with x264 right now, but isn't there some way we could use this external codec? or does vlc just use the h.264 decoder in ffmpeg?

[bob0r]

x264 plays very fine, even high profile plays flawlessly now.

my used settings:

start /low /b /w x264 --progress --pass 1 --bframes 3 --me dia --ref 1 --subme 1 --analyse none --output nul cap.avs
start /low /b /w x264 --progress --pass 2 --bitrate 528 --bframes 3 --b-pyramid --b-rdo --weightb --ref 8 --trellis 1 --subme 6 --8x8dct --analyse all --output video.264 cap.avs

start /low /b /w mp4box -add video.264 x264.mp4
start /low /b /w mp4box -sbr -add audio.aac x264.mp4

note, there is no cqm support yet (for example --cqm jvt)

simply update to latest libavcodec source, and all x264 options should play perfectly fine on your xbox (ofcourse hd resolutions will always be a problem)

but 640x352 plays just fine with the settings above.

[kbart63]

i have started to use h.264 coded videos and am very impressed. the quality on xbmc is excellent.

i thought it would of interest that the people from corecodec (developers of betaplayer and now tcpmp) are developing a avc decoder that is extremely efficient (people are claiming improvement of 60-80% over ffmpeg and also being able to run at full-speed 1080p content on hardware as old as a celeron 800mhz).

they do not have a direct show filter yet and i am not sure if they will let the codec be used in mplayer, but it may be worth some of the developers time to check on this. there are many discussions on doom9 regarding the efficiency of the codec.

http://forum.doom9.org/showthread.php?t=104277/

they have a win32 media player and codec download at link below if your are interested. i am finaly able to watch 720p avc encodes on my 1.7 ghz pentium m. i hope that corecodec's work will help xbmc process higher resolution and enhanced h.246/avc encodes.

http://picard.exceed.hu/tcpmp/test/ (don't forget to download both the player and the avc codec).

enjoy!

[pike]

all i can say is: way ahead of you!

but i can't say anything yet, because nothing has been decided.

[kbart63]

that is encouraging news pike!

cannot wait for matroska containers and avc to replace my full dvd rips. (hopefully the menu filters will be worked out; don't know what the status of getting help from the ratdvd project is).


first dvd menu support and now maybe hd resolution avc encodes...wow!


link below provides some information regarding matroska.

http://www.matroska.org/technical/guides/faq/index.html

[zap brannigan]

corecodec / coreavc looks really good! h264 on xbmc with all the features turned on in 720p would be nice

[Epiphany]

it would be very nice, i am extremely excited about this. when the anime groups started doing h.264 i was scared at first, but now i feel relieved. even if corecodec is going commercial, hopefully we'll be able to pay for like a coreavc plugin for xbmc or something along thoes lines, if we must pay.

xbmc is the reason i bought my xbox.

[jthunder]

pike, can you elaborate at all at what decision is being contemplated? these are exciting times if there is hope that hd avc encodes will playback on the xbox!!!

thanks

jt

[jthunder]

any update to the coreavc issue? is there anyway that we can get the optimized codec included in the base image?

what about including it after the fact, as a separate add-in codec?

it would really suck to know that there is a codec capable of making the xbox shine doing 720p, and the only reason it can't is because of licensing.

what are the chances of having other codecs optimized to the same degree as coreavc?

thanks..

[Gamester17]

for those wanting to encode h264/x264 (mpeg-4 avc) for xbox/xbmc today i recommend megui with sharktooth's custom x264/avc video profiles (using the box profiles obviously)

[pike]

@jthunder

i can't really spill all internal talk

but the proposed deal from them was that we would get some version of the decoder if we helped them with something. our devs unfortunately don't have the time for this, thus it seems gloomy

also, don't know if you seen, but their decoder is going commercial. ~15$ is the price i've seen for the standard version

[Gamester17]

any update to the coreavc issue?  is there anyway that we can get the optimized codec included in the base image?

it would really suck to know that there is a codec capable of making the xbox shine doing 720p, and the only reason it can't is because of licensing.

you will never be able to play native* 720p/1080i avc video on a standard xbox anyway, ...what the coreavc codec could have brought to the table is 'only' smooth playback of all non-hdtv avc videos.

what are the chances of having other codecs optimized to the same degree as coreavc?

actually pretty good (though at some sacrifice of the visual-quality, but smooth-playback is more important isn't it?), problem is finding a developer has the time, skill and devotion/will to to customize the h264-decoder in ffmpeg for the mplayer-core in xbmc,  ...i posted some tips about how to do some optimizations on it earlier in this thread which could maybe be a good start(?). but again remember that it is not realistic to wish/aim for smooth-play back of native* 720p/1080i avc video on a standard xbox with its 733mhz piii processor and 64mb shared ram, what we could maybe hope to see in the future is smooth-playback of all sd (standard definition) video-files on an normal xbox, (and also that sd video then upscaled/upconverted to 720p/1080i by the xbox's tv-output chip). as it is today, the xbox and xbmc cannot even smoothly playback many sd avc videos if they are encoded with cabac and/or deblocking, nor avc videos that have too high-bitrate video at sd combined with a high-resolution or too high-bitrate aac audio-tracks.

* by native 720p/1080i video i mean the real hd resolution of the video files (720p = 1280x720 progressive, and 1080i = 1920x1080 interlaced), compared to sd video (720x480 ntsc, or 720x576 pal).

ps! understand that it's not only the avc/h264 video-codec (ie. ffmpeg in mplayer) that needs to be optimized but also the aac audio-codec (ie. libfaad/libfaad2 in mplayer) must be too.

[jblade]

you will never be able to play native* 720p/1080i avc video on a standard xbox anyway, ...what the coreavc codec could have brought to the table is 'only' smooth playback of all non-hdtv avc videos.

why can't you play native 720p/1080i on the xbox? you can change the resolution the xbox outputs in xbmc to a native hd resolution (which for me has solved my old lag issues i was getting with gaming and my samsung dlp 720p tv). what if you modded the xbox by adding more ram (after all there are slots for it), wouldn't that help.

sort of off subject, but what about smooth playback of .ts files? i dont know if there is a stripped down linux version, but the nvidia purevideo decoder was best for me visually and performance wise. (doesn't matter if you have a nvidia video card or not, works fine with windows media player 10)

[jthunder]

so does the commercialization of the coreavc codec allow us to purchase a personal copy to use with mplayer on xbmc?

i had hoped that it would allow us to playback 1280x720 progressive (60fps) content? if not possible what about 1280x720 interlaced (~30fps)?

anyway i hope this helps us somehow, i'd love to extend the useable life of xbmc on the old xbox hardware.

jt