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Amdh
4th April 2005, 09:05
:)
Hi Everyone in doom9 !
Well .. I have lately Started Using X264 In Order to Compress Slow Motion TV Show Of About 30 Minutes ! However I am still confused and I need advice about the perfect Profile For Such Compression !
Thank U In Advance !
:)

namchik
4th April 2005, 10:54
Hi
don't know about the perfect profile :rolleyes: but with x.264 rev.184 I sticked to default settings and set only deblocking strength to "1"

Zarxrax
4th April 2005, 14:22
Speaking of the settings, has anyone written down what they all do anywhere? I've tried searching for anything that explains all the settings, but I'm not coming up with anything. After encoding with nothing but xvid for the past many years, this is all like a foreign language to me :p

twist3d
4th April 2005, 14:28
i proposed a while ago "recommended x264 settings" sticky but maybe it just got overlooked. would help though.

video
4th April 2005, 14:28
Originally posted by Zarxrax
Speaking of the settings, has anyone written down what they all do anywhere? I've tried searching for anything that explains all the settings, but I'm not coming up with anything. After encoding with nothing but xvid for the past many years, this is all like a foreign language to me :p

I feel we should have the standards... but 150CHF is alotsa money :)

unmei
4th April 2005, 18:40
get it from ITU for free -> look what akupenguin said in his post near the bottom of this page (http://forum.doom9.org/showthread.php?postid=631017). On the page after that one, someone also points to a direct PDF download (maybe tha's an older version tho).

But ..good luck in trying to derive encoding settings from the specs.. :/

Stacey Melissa
4th April 2005, 22:08
@twist3d - see the mencoder commands page (http://www.mplayerhq.hu/DOCS/man/en/mplayer.1.html). Near the bottom it has a -x264encopts section, which lists and describes x264-specific encoding options.

twist3d
5th April 2005, 05:54
@Stacey, those are for mplayer (i use the vfw builds) and still a complete hebrew for me (and there is no general recommended settings as I stated earlier). well off to test the latest xvid beta :D ->

Stacey Melissa
5th April 2005, 06:07
Yes, those are for mencoder, but they are exactly the same options that the vfw interface uses. Most of them even have the same names. And if you read the option descriptions, the manual tells you what the "sane" ranges are.

There's no general recommended settings because the codec can be used for all sorts of different tasks, and each task calls for different settings. I do non-scaled anamorphic high bitrate DVD rips. My defaults are going to be different from someone who does downscaled square-pixel DVD rips at lower bitrates, or someone who does TV capture transcoding. So just use the default settings as a starting point, then tweak and experiment to find what you like best.

Stacey Melissa
5th April 2005, 06:39
Originally posted by Amdh
I have lately Started Using X264 In Order to Compress Slow Motion TV Show Of About 30 Minutes ! However I am still confused and I need advice about the perfect Profile For Such Compression !
Can't tell you want the perfect profile would be, but I'd suggest you start by playing around with number of b frames, deblocking strength, enable/disable 4x4mv, enable/disable weighted b frames, enable/disable chroma motion estimation, and of course tweak the bitrate.

Amdh
7th April 2005, 10:10
:)
Thank U EveryOne ! I will Stick To The Default Settings !
By The Way I Was Using The following Profile :
Quantizer=23 and Sometimes 25
Deblocking=1 and Sometimes 2
Max IDR Frame=300
Min IDR Frame=5
I got A bitrate of about 70 to 95 kbps !
Is This Right !
Note : Video Resolution = 384*320
:)

Stacey Melissa
8th April 2005, 03:37
Your min IDR setting seems ridiculously low. Other than that, there's nothing wrong with your settings. If the quality and bitrate are good enough for you, then leave everything else alone. If not, start tweaking. That's how you can know whether you've got the right settings.

Selur
8th April 2005, 06:51
"has anyone written down what they all do anywhere?"
I wrote something like that for the vfw x264 GUI in German, German speaking readers can grab it over here (http://www.flaskmpeg.info/board/thread.php?threadid=5138).
(it's named 'Wissenswertes rund um x264')

Cu Selur

stephanV
8th April 2005, 09:08
Originally posted by Amdh
:)
Thank U EveryOne ! I will Stick To The Default Settings !
By The Way I Was Using The following Profile :
Quantizer=23 and Sometimes 25
Deblocking=1 and Sometimes 2
Max IDR Frame=300
Min IDR Frame=5
I got A bitrate of about 70 to 95 kbps !
Is This Right !
Note : Video Resolution = 384*320
:)
q = 23 and q = 25 in AVC roughly correspond with q=3.5 and q=4.5 in ASP, so your bitrates seems indeed very low for that sort of resolution (what kind of res is that anyway?)

Amdh
12th April 2005, 14:25
:)
Thank U Stacey Melissa For Ur Comment .. I Will Correct That .. Maybe I Will Set It To 25 .. By The Way What does it Mean in reality !

:)

Amdh
12th April 2005, 14:28
:)
Dear stephanV
The Bitrate Seems Low however I got Good Quality Coz I'm Compressing Slow motion TV Shows !
About The Resolution It Seems Sufficiant For My Purposes !
:)

Stacey Melissa
12th April 2005, 18:31
Originally posted by Amdh
Maybe I Will Set It To 25 .. By The Way What does it Mean in reality !
IDR frames are the only kind of seekable frames in x264. So if you like to skip around your video a lot, it would be good to have fairly low IDR values. The max IDR value is the more important one for that, though. The CLI interface for x264 defaults to Min IDR=25 and Max IDR=250. Mencoder defaults to 100 and 250, respectively.