February 2007 - MEncoder-users - lists.mplayerhq.hu

H.264 quantization matrix files?
by Grozdan Nikolov 04 Feb '07

04 Feb '07

Hi, I'm trying to get some good H.264 quantization matrix files to experiment with here and load them with cqm=), but after looking for 2 days on the Net, I didn't find any and I don't really know how to build one myself. I know the graphical tool of libx264 (x264_gtk_encode) can build them, but I don't know what I should enter there. Does anyone has a link to where I can get some good matrix files for H.264? Thanks in advance, GN

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test
by Bayrouni 04 Feb '07

04 Feb '07

Sorry, just testing.

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Join MP4 Files?
by Matt 03 Feb '07

03 Feb '07

Hi all, I'm trying to join two mp4 files with mencoder. After some reading, I've come up with the the command below. I also included the end of the mencoder output. Is it possible to join files like this? Command Line: mencoder -oac copy -fafmttag 0x706D -ovc copy output.mp4 output2.mp4 -o JoinMe.mp4 End of output: All files must have an identical audio codec and format for -oac copy. Exiting... Help?? The files are actually a copy (they are the same file, just renamed). Thanks in advance.

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Next-Gen YouTube type question.
by Robby Dermody 03 Feb '07

03 Feb '07

Hi guys, video processing newbie here. :-) I have a question about live/on-the-fly video transcoding and streaming. Specifically, for the easiest end-user acceptance this may involve mencoder, the flv file format, and a flv streaming server (lighttpd with appropriate plugin in this case). Think about a YouTube type setup that allows users to watch videos live, as they are being produced. FLV would be the format of choice due to the widespread availability of Flash player, and the lack of ActiveX warnings, java incompatibilities/speed, quicktime/realplayer hassles, etc. Seems like Flash Just Works (witness Google Video and YouTube). >From the research I've done, the setup would go like: take in LIVE video feed in format X from some source -> mencoder convert to flv -> named pipe -> file location readable by lighttpd with flv-streaming module setup, allows for live streaming of this file (with obvious transcoding and network propagation delays) After doing some research it seems that this wouldn't work, due to the lack of metadata in the flv stream which the flv-streaming module and more importantly flash player need. I'm not sure if the flv format can even be composed and distributed on the fly like that. And, from looking at flvtool2, it looks like the complete file needs to be in place before it can write out this data? Is there any way to get the metadata data that flash player needs in the flv as it's being output? Another possible issue is if mencoder can reliably take data from stdin like that..it looks like it isn't recommended. Other alternatives involve using an activeX control to play a live ogg theora/nsv stream produced in the same fashion and served up with icecast/shoutcast. If FLV doesn't work out, I may ask the same question to the xiph guys. In any case, I would think the video producer app would either have to be an activeX/java-type control or an actual application. Any ideas from the resident gurus welcome. Robby

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2 green frames at begin when using vf yadif
by Bernhard Schelling 02 Feb '07

02 Feb '07

Hi all, When I use the yadif filter with an avi output I always get the first 2 frames filled with green (RGB 0,135,0). I tested this with different mencoder versions on different platforms with many different input files. It seems to me, as it is a 'behavior by design' as yadif probably (I'm just guessing here) needs at least 3 frames to work with. So the first two don't meet this requirement and the result are these green frames. It's hard to see when looking at it in mplayer (you can see it very good when you press the left key down) but it's not that nice either. You can see it of course in a video editing tool or in some video preview utilities which grab the first frame for instance. So I'm looking for someone who can fix this or include a workaround, or provide me with a way to have these frames either removed, or not filtered by yadif. I'd like to do this without having to encode the whole file twice or storing full raw frames on a storage device. Thank you, Bernhard

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Back to dvd
by listman 02 Feb '07

02 Feb '07

I'm ripping all my dvd's to my server using. mencoder "dvd://$TRACK" -aid "$AID" \ -mc 0 -oac lavc \ -ovc lavc -of mpeg -mpegopts format=dvd:tsaf -vf scale=352:240,harddup \ -srate 48000 -af volume=8:lavcresample=48000 -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:\ vrc_maxrate=9800:vbitrate=2900:keyint=18:aspect=16/9:acodec=ac3:abitrate=192 \ -ofps 30000/1001 \ -o "$STORE/$TITLE".mpg everything works great, but when I run dvdauthor -o dvd -x dvd.xml then growisofs -dvd-compat -Z /dev/dvdrw -dvd-video ./dvd/. and try to play it on my dvd player it doesn't work, would the scale be throwing things off? the docs say that is an except able scale for dvd. I have also tried autoaspect and get the same results. the audio is fine but the video looks like I have too high a setting on an old crt monitor. Is there another way to create a dvd? I tried kino but that takes way to stinking long.. Thanks for any advice

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How I can make a color correction when encode moving jpg to mpeg4?
by Strong 02 Feb '07

02 Feb '07

How I can make a color correction when encode moving jpg -my photo camera records- to mpeg4?

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Re: Native Vorbis audio support in libavcodecs/MEncoder?
by Grozdan Nikolov 01 Feb '07

01 Feb '07

On Thursday 01 February 2007 11:02:01 you wrote: > Hi, > > Maybe a silly question, but why isn't there native Ogg Vorbis support in > libavcodecs? I mean, I can encode the audio of my DVDs to MP3 (if linked to > libmp3lame) or AC3, but MEncoder does not support encoding directly to > Vorbis audio... Why is that?

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