ffmpeg doesn't like 1080p H.264 files?

[JimXugle]

I'm trying to use ffmpeg to down-scale a 1080p H.264 file (no audio) down to 720p H.264 for easy storage. I've tried multiple windows builds, the build that came with kubuntu (7.10 I believe), and a fresh build from SVN with fresh dependencies. All of these seem to freeze after about 3 seconds of execution and just eat CPU cycles.

Here's the command I'm trying to use:

ffmpeg -i Track1.h264 -vcodec libx264 -s 1280x720 -an Track1_720.h264

Is there a patch for this or a (preferably free) different way to get this scaled?


Thanks!

[Guest]

You can try opening it in DGAVCDec:

http://neuron2.net/dgavcdec/dgavcdec.html

If it plays in VLC, it will probably be OK in DGAVCDec. If not, then not.

[JimXugle]

Well, it plays in VLC and DGAVCDec... just at a horrible frame rate -- which is another reason why I'd like to scale the video down. I went through trying to get AVISynth, DGAVDec, and VirtualDubMod to work to scale it, and after multiple 12 hour renders, I found myself with a 6MB file thats the length of my video... sans video.

Is there a n00b-friendly way to do this?

[J_Darnley]

No, high definition and AVC aren't exactly easy to use yet. Neuron2 and his DGAVCDec plugin makes it a lot better though. Once you have run it through AVCIndex you then just load the dga file into your script with a call to the decoder and then you can treat it like any other video from any other source.

If you are having problems with the encoding side I will remind you of Trim()

You could also try ffmpegsource (http://forum.doom9.org/showthread.php?t=127037) which might load the source file without messing with intermediate steps.

[SeeMoreDigital]

Sorry to ask the obvious....

But how powerful is your PC's CPU?

[JimXugle]

It's not obvious, it's a valid question!

My windows box has an AMD Athlon 64 3500+ Venice with 1GB of Ram, and my Linux box is running on an Intel Pentium 4 "Northwood" at 2.4GHz, also with 1GB of Ram.

Sure, It's not great hardware.... but it seems to work.

[JimXugle]

Overall, this is just frustrating me. Here's what I've come up with so far:

Track1.h264 (11GB) -- The source file

Track1.dga (2.7MB) -- the DGAVCDec output of Track1.h264

Track1.avs:
LoadPlugin("DGAVCDecode.dll")
AVCSource("Track1.dga").BilinearResize(1280, 720)
(yes, DGAVCDecode.dll is in my path)

When I open Track1.avs in VirtualDub, and try to save the video as AVI, it says that the resulting file will be over 700 GB!

-_-;

I don't have 700GB of drive space at my disposal... few people do. Is there an AviSynth function I haven't found that will re-encode the resized frames into H.264 on the fly?

[J_Darnley]

What are you encoding it with? By default VDub will save uncompressed RGB. If you don't want that then you need to set an encoder (and Direct Stream Copy if you aren't processing in VDub).

[JimXugle]

Yes, I did have the encoder set to default... thanks for pointing that out.

Now the final problem (I hope) is finding a dll that will encode into H.264. Googling leads me in circles to x264.nl (http://www.x264.nl/), and rolling my own libx264 on cygwin leads me nowhere.

[J_Darnley]

Well if you really need to use the VFW version instead of the CLI (or with a graphical front end) you can see a guide here:
http://forum.doom9.org/showthread.php?t=98247

Or are your looking for another encoder, mencoder or ffmpeg perhaps?

[audyovydeo]

It's just occurred to me that you can use avidemux, a very good (and sadly underrated, I think) utility :

home : http://avidemux.org/
latest builds : http://www.razorbyte.com.au/avidemux/

multiplatform, too.

cheers
audyovydeo

[JimXugle]

Thanks, J_Darnley, thats exactly what I was looking for.

audyovydeo, I'll be sure to check that out.

Thanks for your help!