help: jerky/freeze video playback after using mencoder

[keratos]

Hi

I'm using devede on linux 2.6.20-15 to encode a DVD from AVI (DivX).

I've installed latest mplayer (includes mencoder version: dev-SVN-r22974-4.1.2).

Devede is shelling the following command to mencoder:

program:  ['mencoder', '-oac', 'lavc', '-ovc', 'lavc', '-of', 'mpeg', '-mpegopts', 'format=dvd:tsaf', '-endpos', '20.0', '-ofps', '25', '-vf', 'expand=576:324:0:42,scale=720:576,harddup', '-lavcopts', 'vcodec=mpeg2video:trell:mbd=0:vstrict=0:vrc_maxrate=7501:vrc_buf_size=1835:vbitrate=5001:keyint=15:acodec=mp2:abitrate=224:aspect=16/9', '-o', '/var/tmp/movietemp_01_01.mpg', '/home/potc.avi']

Now, what happens when I play the output back either through windows, linux, commercial TV or even a standalone DVD player, the output "feeezes" every second or two seconds. The "freeze" is like a pause for maybe half a second, perhaps a quarter of a second. It looks like the move stops and rewinds a few frames because the images seem to "jump" back before playing another second or so, then the whole thing is repeated.

I've used Avidemux to create the same film from same source and playback is okay. I don't know what command avidemux is using but devede is using mencoder.

Is there something I can tweak in devede.

I'd like to stay with devede because it is very simple to use and creates and iso file...avidemux keeps crashing despite upgrades, lib installs, etc.etc.

Please help!

thanks.

[Forum Troll]

Is it keeping the framerate at 25, or doing a pull-down to 23,976?

[keratos]

how do i tell?

what its doing...is whatever it is programmed to do given the command I provided above which is the command and parameters that are being passed to mencoder by devede.

[tekkieman]

'-ofps', '25'

The framerate is definitely 25fps.

I don't know if this resize may be causing an issue

'expand=576:324:0:42,scale=720:576,harddup'

I understand wanting to use devede for ease of use, but you might try to do the conversion with tovid and see what the results are like, or manencode/mandvd.

[FulciLives]

Is there a Linux version of GSpot or something similiar?

Would help if we knew the exact details of the AVI file such as the frame rate and resolution etc.

- John "FulciLives" Coleman

[tekkieman]

Is there a Linux version of GSpot or something similiar?

Would help if we knew the exact details of the AVI file such as the frame rate and resolution etc.

- John "FulciLives" Coleman

avinfo, Avi-Ogm Info or tcprobe

[keratos]

Is there a Linux version of GSpot or something similiar?

Would help if we knew the exact details of the AVI file such as the frame rate and resolution etc.

- John "FulciLives" Coleman

but they too use mencoder and/or transcode. They are just front ends to what I am already using via devede no??

I've downloaded and installed mandvd. Will give it a go.

[keratos]

see below for AVI details:

$ tcprobe -d 1 -i potc-cd1.avi
[tcprobe] RIFF data, AVI video
[avilib] V: 23.976 fps, codec=XVID, frames=99416, width=576, height=240
[avilib] A: 48000 Hz, format=0x2000, bits=0, channels=5, bitrate=448 kbps,
[avilib]    43193 chunks, 232200781 bytes, CBR
[tcprobe] summary for potc-cd1.avi, (*) = not default, 0 = not detected
import frame size: -g 576x240 [720x576] (*)
       frame rate: -f 23.976 [25.000] frc=1 (*)
      audio track: -a 0 [0] -e 48000,0,5 [48000,16,2] -n 0x2000 [0x2000] (*)
                   bitrate=448 kbps
           length: 99416 frames, frame_time=41 msec, duration=1:09:06.479

THANKS GUYS FOR STICKING WITH ME!!

[keratos]

dvdman was awful!

output was worse and its a QT app so looks poor on my ubuntu distro. Also, user is forced to create menus ... I dont want a menu, its a single track DVD with one film. I never create menus.

I'm sure its a fine app under KDE for other uses though

[FulciLives]

Well now it is obvious to me ... you have a 23.976fps AVI and you are trying to make a 25fps MPEG-2 DVD spec file.

If you are getting jerky playback then it most probably is due to incorrect frame rate conversion.

I don't know Linux and don't use linux programs but there is a Windows application called DGPulldown which is recommended for PAL to NTSC or NTSC to PAL. Basically you could still do your encoding under Linux but encode at 23.976fps yet with a PAL DVD compliant resolution (like 720x576). Then you run the resulting video file through DGPulldown (which I think works under Wine from what I've heard) and you end up with a new video that will be 100% PAL compliant.

So again set up the encode as you would for NTSC but do NOT apply 3:2 pulldown. Simply encode as "straight" 23.976fps BUT do change the resolution to a PAL DVD compliant resolution.

Run the resulting video only file through DGPulldown using the custom option (23.976fps ---> 25fps)

The new file is now PAL DVD compliant and will be the same length as the audio file that is in the AVI file ... in other words no need to change the length of the audio file (although sometimes you do need to adjust the initial dealy value).

- John "FulciLives" Coleman

[keratos]

I've tried mencoder options, lots of them, for three weeks now. I'm playing around because I am in no way experienced enough for this.

I've encoded to 23.976fps, to 24 to 25. I've tried PAL, NTSC. no frame skip, softskipping, harddup all sorts.

Avidemux does the job - what command is it using I wonder.

Trouble with avidemux is that it doesnt create DVD ISOs and only does a single file convert at a time (no good for mutiple streams into MPEG2).

Does anyone have/know a way to "interrogate" what avidemux is doing in terms of encoding command or do you have the linux mencoder command I could use?

[keratos]

have we given up?

[tekkieman]

have we given up?

No, have you?

Convert any video file to DVD

[keratos]

No!

I was hoping for some assistance dear tekkieman

avdiemux debug??

[tekkieman]

You could try running it from the command line as "avidemux --nogui" which, strangely enough, gives you a gui, but will output many messages to the console.

[keratos]

You could try running it from the command line as "avidemux --nogui" which, strangely enough, gives you a gui, but will output many messages to the console.

thanks. I will try this soon.

[keratos]

Tried the --nogui. This didnt reveal anything.

Ok, I've googled and hacked a bit.

The problem is as suggested above, converting 23.976fps to 25fps. Extra frames are being added and causing the "stutter" or "freeze".

If I convert to PAL and write to DVD then playback on both my PC and settop box "stutters" every second or so.

If I covert to NTSC and write to DVD then playback the DVD on my PC , then all is fine. If I take the same DVD and pop it into my setttop DVD player, then I get the stutter.

So NTSC->NTSC okay(ish)
NTSC->PAL (never okay).

I've used devede which uses mencoder. Apparently I need to doa 2:3 pulldown. What is this and what options in mencoder do I need.

Thanks guys in advance for your kind assistance.

[ahaslam]

Sorry for digging up an old thread. This is one of a few that has received constructive replies & I know how frustrating it is for there not to be a definitive solution. After testing all manor of filters & encode opts, I came up with this:

mencoder x264.mkv -of mpeg -mpegopts format=dvd:film2pal -srate 48000 -ofps 24000/1001 \
-ovc lavc -oac lavc -lavcopts vcodec=mpeg2video:threads=2:vrc_buf_size=1835:\
keyint=15:vrc_maxrate=9800:vbitrate=4900:mbd=2:mv0:trell:aspect=16/9:\
acodec=ac3:abitrate=256 -vf expand=aspect=16/9,scale=720:576,harddup -o dvd.mpeg2

The magic happens with the 'film2pal' mpegopt. This doesn't prevent the stutter as you're still missing 1fps. though it does prevent the backward jump, making it much less noticeable.

I hope this is of some use.

[FulciLives]

If you were working in MS Windows I would tell you to encode your NTSC source to a "hybrid" video only file. Basically one with a PAL DVD compliant resolution but still at 23.976fps with no pulldown.

Then you would use DGPulldown to do 23.976fps ---> 25fps pulldown.

That works really well but I don't know when using Linux apps how easy the first part is (I'm guessing not hard) not to mention you would have to use DGPulldown and hope it works under WINE.

- John "FulciLives" Coleman

[ahaslam]

Being new I find different terms confusing. My example uses telecining, I assume 'pulldown' is similar? The resulting file is 25fps, though I'm sure it simply duplicates the occasional frame to achieve this. The result is far superior to having not used it. Admittedly, it's not quite as fluid as the original 23.976fps file, though this is only noticed when the camera is moving.

I have used the fps conversion filter within Avidemux & the result was not as good as what's achieved with the 'film2pal' option. Following the assumption that pulldown is the same or similar to telecining, I don't see the need to use any MS applications within Wine.

Another way to achieve 25fps would be speeding the video up by 4%. I doubt the speed difference will be noticed visually & the result should be as smooth as the original. The only doubt I have lays with the audio & the extra overhead of a filter to correct the inevitable pitch increase. I'll try this for my next DVD & let you know if mencoder provides the goods.

[ahaslam]

The speed increase works well, producing a fluid video.

mencoder x264.mkv -speed 1.0427 -of mpeg -mpegopts format=dvd -srate 48000 -ofps 25 \
-ovc lavc -channels 6 -oac lavc -lavcopts vcodec=mpeg2video:threads=2:vrc_buf_size=1835:\
keyint=15:vrc_maxrate=9800:vbitrate=6400:mbd=2:mv0:trell:precmp=2:subcmp=2:\
cmp=2:dia=-10:predia=-10:cbp:vqmin=1:lmin=1:dc=10:vstrict=0:aspect=16/9:\
acodec=ac3:abitrate=384 -vf expand=aspect=16/9,scale=720:576,harddup -o dvd.mpeg2

The 'speed 1.0427' option increases the speed to achieve the required 25fps. The only negative to this method is the slight increase in audio pitch. If you have either a pre-rc or svn mencoder the 'scaletempo' audio filter should avoid this.

Now you have 2 different native options

[FulciLives]

My understanding is that all commercially made PAL video from film is sped up to 25fps without pitch change. Apparently you aren't supposed to notice the pitch change (knock on wood) and trying to adjust the pitch will cause more harm than good.

At least that is what I've been told.

Of course in reality people say the no pitch changing is bad for musical performances and in the few cases where commercial releases were "pitch adjusted" apparently it sounded like ass as well.

Again things I've heard over the years.

- John "FulciLives" Coleman

[ahaslam]

The pitch change is certainly noticeable when you run both at the same time. In normal circumstances you'd likely not notice though.