I occasionally have footage to take off my MiniDV camera and need to convert it to a format that I can easily burn and archive. I am not much into mastering DVDs, just being able to play the file on my computer is good enough for now.

I've been using kino to do this job before, but that is hard to script. So I decided to play a bit with mencoder. I have no idea what I am doing, so I tried to encode at the highest possible bitrate/quality I could get out of the DivX (mpeg4) encoder.

First the capture... I use dvgrab to get the data off my firewire-connected MiniDV camera. Just running 'dvgrab' will capture all video (until you stop it) into files of the name dvgrab-001.avi, dvgrab-002.avi, etc. The format is avi, but it's still raw data inside. So it's huge. The files are split every 1 gigabyte by default.

To encode it I am using the following command:

mencoder dvgrab-001.avi -o video-001.avi -vf hqdn3d,kerndeint -ovc lavc -lavcopts vcodec=mpeg4:vqscale=1:vhq:v4mv:vbitrate=8000:threads=2:acodec=ac3 -oac lavc
The intent is to deinterlace, enhance, and compress with the highest possible quality preserved. There is a lot of information in the mencoder documentation, but here are the select bits from the above command:
  • -vf hqdn3d,kerndeint
    apply a high precision/quality denoise 3D filter, and
    apply Donald Graft's adaptive kernel deinterlacer.
  • -lavcopts vcodec=mpeg4:vqscale=1:vhq:v4mv:vbitrate=8000:threads=2:acodec=ac3
    use mpeg4 from the libavcodec,
    (vqscale=1) with highest fixed quantisation (huge files),
    (vhq) high quality macro block decisions,
    (v4mv) allow 4 motion vectors per macroblock,
    (vbitrate=8000) very high datarate cap,
    (threads=2) use multiple threads, and
    (acodec=ac3) use ac3 audio encoding.
The raw DV files were compressed about 10:1 with the above configuration.

Also started using dvd+rw tools for burning... since the cdrecord support for DVD+RW drives is incomplete (there is an unsupported patch that sometimes works). Here is how you burn an iso to a DVD:

  • growisofs -Z dvd.iso
... and that's it.

Next, I need to find some time to read the mencoder doc and revise the above. I should also start using the double pass encoding -- apparently gives a better picture quality.

Also, the fixed quantisation has a negative (side)effect of wasting the data rate, I will have to see what quality I get at higher vqscale settings.

Finally, the dvgrab program splits on 1G boundaries, where I would much prefer a scene split -- like kino allowed in post processing. mencoder could possibly do this, just have to find out how.

Here are some related links: