Cmd Line MPEG4 Encoder - ffmpeg

[mlbdude]

Just an update. I have compiled a bunch of VirtualDub scripts and done some testing. As normal compression works fine, but no matter what I don't see a way to get VDub to go silent. It still pops up a window when opening the file and if an error occurs another modal dialog pops up waiting for user interaction.

Seems like we may be at an end on this for now. If anyone comes up with something let me know.

Thanks for all the efforts!

[Bubster]

Erm, haven't we given up on ffmpeg a bit too easily? I mean, it works perfectly for some people (myself included), so there's a good chance we can figure out what isn't working for the others.

On a side note, I got the XviD patch building, so we can use ffmpeg for both DivX and XviD if we can sort out this niggly sound dropout issue.

If ffmpeg does prove to be a bust, then I could have a go at removing the windows stuff from VirtualDub, but ffmpeg seems the better, faster option if we can get it working for everyone.

- Neil.

[mikejaner]

Um, I don't know if this was mentioned before, to lazy to look, but has anybody looked into mpeg2avi? I don't think it's been developed for a while, but I remember doing command line encoding with it a few years back.

[Crashless]

Originally posted by mlbdude
Just an update. I have compiled a bunch of VirtualDub scripts and done some testing. As normal compression works fine, but no matter what I don't see a way to get VDub to go silent. It still pops up a window when opening the file and if an error occurs another modal dialog pops up waiting for user interaction.

Seems like we may be at an end on this for now. If anyone comes up with something let me know.

Thanks for all the efforts!

Is there maybe a way to run it from within Alex's java starter? That has settings for priority and starting minimized. Which window are you having problems supressing? The loading status? Which error boxes are you seeing? Maybe we can try convincing the developers to implement a /supress flag to write a log file on errors.

[mlbdude]

Originally posted by Crashless
Is there maybe a way to run it from within Alex's java starter? That has settings for priority and starting minimized. Which window are you having problems supressing? The loading status? Which error boxes are you seeing? Maybe we can try convincing the developers to implement a /supress flag to write a log file on errors.

It is definitely possible to run from the java program but it won't keep all the windows hidden. So until we get the pop-ups removed It would not work on a SageTV server, but could work on a PC not being used. Unless an error comes up then a dialog pops up and waits till you say "OK" before execution continues.

[Bubster]

Originally posted by mikejaner
Um, I don't know if this was mentioned before, to lazy to look, but has anybody looked into mpeg2avi? I don't think it's been developed for a while, but I remember doing command line encoding with it a few years back.

I had a quick look at mpeg2avi and it seems that it doesn't handle audio. They suggest that you use VirtualDub to multiplex your audio back into your avi once you have used mpeg2avi to compress the video stream, so this brings us back to the issue of hiding VirtualDub while it is processing.

[mikejaner]

Ahh, forgot about the no audio thing.

[Bubster]

Has anyone managed to generate a small output file using ffmpeg, with the sound dropout issue?

The ffmpeg dev mailing list seems to be pretty active, and the maintainer will look at problems if he is given enough info to work on, if we can't figure it out ourselves.

[Crashless]

Originally posted by mlbdude
snip...Unless an error comes up then a dialog pops up and waits till you say "OK" before execution continues.

I found a setting in VirtualDubMpeg2 that allows you to set your error preference. You must set it under both video and audio menus, and it is called 'error mode' and set to 'decode even if reslt may be garbled'. Set for both audio and video, and it seems that as long as the 3rd party plugins don't crash, we'll be fine.

At least that's what it seems. I have never had a crash from within the virtual dub program to know what happens.

That said, I've experimented with another program called DubMan it makes a MUCH easier execution of the virtualdub script, and it seems to be much more robust, also, its script uses XML so we may be able to create those files on the fly. I say we only by habit, I can't code my way out of a paper bag, only hack together other people's code. Does this help anyone?

It probably would be easier for most to just create a new 'wildcard' template than to modify mine, but basically you need to replace the input and output files in the template with the appropriate paths, then put it and the bat file in the dubman directory and run. You must setup dubman first with the needed paths to virtualdub. If you make your own job template for DM, click the 'bulk settings' button in the bottom left then set 'wildcard' then in the input and output files of the job configuration screen, set the full path of your source/destination directory, as *.mpg for source and *.avi for output. I got stuck here and only put *.mpg/*.avi without paths, and it didn't do anything.

It ran VDub minimized, the only popup was dubman and the 'loading' window from VDub. I haven't tried the java wrapper, but I don't see why it wouldn't hide dubman.

One problem though, it quit VDub like it was supposed to, but then sat and waited on a 'I'm done!" dialogue box. Dumbass, I put /q on the command line, what gives? I don't have an answer to this one yet.

Oh, yeah, it also has a setting to delete source file when done. It did this as advertised.

Dubman has the ability to execute external command line programs as a script as well as run VDub, so you could feasibly create an XML template file for dubman that would do all the copying, encoding, deleting, automatically. with no need for the extra steps I took by replacing alex's ffmpeg with xcopy (see previous post)

Am I just complicating things? It seems to work though.

Also, the strength to using this script is that you can apply as comlicated of an encoding job as you want. You could package it neatly with default settings, vcfs, & dubman templates, and the 'set and forget' crowd would be happy, then the L337 crowd could run through multipass xvid/ogg bliss. Just a thought.

Sorry for long post, I guess I rambled a bit....I'm just excited, that's all....

[Crashless]

Is anyone still interested in this? My method seems to work. I have it running on my server that uses a pvr350, so the windows poping up all over the place never bothered me, but it has been working.

If hope has been abandoned, will the 'compress' option be dumped in future releases of this stv? That would be a shame as I know many people are interested in this functionality.

I guess I'm asking: Am I alone in my desire to have this work?

Thanks for listening.

[edbmdave]

Originally posted by Crashless
Is anyone still interested in this? My method seems to work. I have it running on my server that uses a pvr350, so the windows poping up all over the place never bothered me, but it has been working.

If hope has been abandoned, will the 'compress' option be dumped in future releases of this stv? That would be a shame as I know many people are interested in this functionality.

I guess I'm asking: Am I alone in my desire to have this work?

Thanks for listening.

Crashless: Yes I think people are interested. MlbDude is out of touch until either this weekend or start or next week, so things have just gone silent for a while. Keep the faith.

[Crashless]

Ahhh, the world makes sense again. Didn't know he was out of town (or whatever) thought it was kinda strange that he was MIA.

Thanks.

[Bubster]

I'm still very keen to get this working as well, although I do think ffmpeg is the more useful option, if we can get it working for everyone. Unfortunately, no-one has been forthcoming with any info that I can use to debug the sound dropout problems, so there's nothing I can do about it, as it seems to work OK here.

The main issues with using VirtualDub for me are that it seems to be slower than ffmpeg (including the enormous amount of time it spends just parsing the MPEG2 file), and the windows popping up are a problem for me since I'm using the displays on all my PCs.

While I'm sure it should be possible to modify VirtualDub to keep the windows from appearing, I did spend quite a bit of time getting a decent build of ffmpeg with mp3 and XviD support working, only to have virtually no feedback, so I'm reluctant to spend any time on a VirtualDub modification in case that runs out of steam as well.

- Neil.

[RedCoat999]

Bubster,
I am very interested in this. I haven't tried it yet since I try to wait until more people have had a stab (and my box is only a PII 450, so a little apprehensive as to how long these things will take to encode).

But if no-one else is trying this then I will have a go. Do you have a build, or instructions, any particular posts I should look at, etc?

Thanks for all you and others hard work.

[davey_fl]

After countless tests with ffmpeg I have to say that I'm not happy with the compress quality. Looking through the fourcesorge forum it would appear that it should be a reliable mpeg4 compressor. My main issues are that I have to up the bitrate to 1900kb/s to remove the artifacting from scene changes, which in turn reduces the compression ratio to a point where it's not worth using. With VirtualDub and the Divx codec running at its default 900kb/s I get excellent picture quality and very good compression ratio. Also with ffmpeg I also (as everyone else does) get audio loss with 2 hour shows. I have tried the - t 30 and this makes no difference, the audio loss is still present. Maybe we need to keep trying different settings with ffmpeg...

my 2 c.

davey

[Bubster]

Originally posted by RedCoat999
Bubster,
I am very interested in this. I haven't tried it yet since I try to wait until more people have had a stab (and my box is only a PII 450, so a little apprehensive as to how long these things will take to encode).

But if no-one else is trying this then I will have a go. Do you have a build, or instructions, any particular posts I should look at, etc?

Thanks for all you and others hard work.

You can get the version of ffmpeg I built here.

Here's a sample command line to use with it:

ffmpeg -y -hq -i INFILE.mpg -f avi -b 1200 -vcodec mpeg4 -acodec mp3 -ab 128 -deinterlace -async 1 OUTFILE.avi

The main issue people are having is that, if they compress a very large mpeg2 file (e.g. a 2-hour show from Sage at 3GB/hour), the sound disappears after 10 seconds or so.

What I was hoping to do was find out where the problem was, e.g. by swapping broken/working files between people (chopped versions of course) to see if there's a pattern.

One way to test this is to put "-t 30" in the command line, which forces it to only convert 30 secs of video, and if you get sound dropout, send it to me or someone else who doesn't have the problem and see if it works there. If there are people willing to do this, I'll put up some ftp details where they can put/get files.

- Neil.

[Bubster]

Originally posted by davey_fl
After countless tests with ffmpeg I have to say that I'm not happy with the compress quality. Looking through the fourcesorge forum it would appear that it should be a reliable mpeg4 compressor. My main issues are that I have to up the bitrate to 1900kb/s to remove the artifacting from scene changes, which in turn reduces the compression ratio to a point where it's not worth using. With VirtualDub and the Divx codec running at its default 900kb/s I get excellent picture quality and very good compression ratio.

The problem with scene changes is probably due to the "group of pictures" setting (-g 300), if you are using a similar command line to the ones given earlier on this thread. If you remove this (and the bframe one, "-b") then scene changes should work properly at lower bit rates.

This is because the group of pictures setting is forcing the compressor to only use an I frame every 300 frames. You can't really represent a scene change with P or B frames, so if the change doesn't occur very near the end of a group (unlikely, as a group of 300 is 10 seconds long for NTSC), you will see a pile of blocks as the P/B frames try to compensate, which they can't.

Also with ffmpeg I also (as everyone else does) get audio loss with 2 hour shows. I have tried the - t 30 and this makes no difference, the audio loss is still present. Maybe we need to keep trying different settings with ffmpeg...

Well, I did ask people to come back with the results of the -t 30 test and we could take it from there, but no-one did. Also, it's not true that everyone is having this issue. I am not, for one.

If you, and any others who are getting the problem are willing to upload the resulting files (the -t 30 ones, of course) to my ftp server, then we can see if the files play ok for other people. Conversely, I (and others who get it to work) could upload files which work for us, and people who are having problems can get them and see if they work. By doing this, we may be able to determine if the fault is in compression or decompression. We can also provide the ffmpeg maintainer with faulty files and see if he can debug the problem.

- Neil.

[davey_fl]

I thought it had something to do with the number of reference frames used and changes in between, I'll give that a try. I'm not at home now, but will create another -t 30 file and PM you for the upload.


thx

davey

[Bubster]

Originally posted by davey_fl
I thought it had something to do with the number of reference frames used and changes in between, I'll give that a try. I'm not at home now, but will create another -t 30 file and PM you for the upload.

OK, cheers. And I'll put a file that works OK for me there, so you could try that and see if the sound is ok on your machine. I'll post the ftp details here, so others can post/try stuff if they want.

- Neil.

[Crashless]

I'll give your xvid a try, but won't be able to until next week. I'd still prefer divx, as I have an MVP that I'd like to be able to play the resulting videos on. But since I have a solution I'm happy with for now, I don't mind helping you guys out. But unfortunately, I can't until next week.

Bubster, please don't give up on us. I've recently realized that this community is much less excited (in general) about beta testing complex solutions than say, the Meedio community. Not that that's bad, it's just a result of the people that are drawn to different solutions. Once you get a solution though, and streamline it for newb-friendly installation, people will love you. I guarantee it.