I wasn't satisfied with the quality produced even using 'mplayer' preset. There is really excessive blockiness, which tends to be a feature of MPEG-4 anyway, but in this case it is far too apparent.

So I've been exploring different mencoder options and making some comparisons.

Anyway I've found the culprit isn't bitrate (mostly), it's the fact that various extremely important codec options are not being used, namely mbd, v4mv, and trellis, while the unsharp filter is used but offers no clear benefit. After doing some tests and timing the encodes as well as looking at the output visually and comparing the numbers I can definitely say that adding mbd=2:v4mv:trell to the codec options adds to the encode time, but using the turbo option more than makes up for that, the total two pass encode time becomes shorter overall. The bitrate dictates the filesize so that remains unchanged. The huge difference is in the quality of the output. It is transformed and looks absolutely fantastic even with very challenging scenes.

Another change that would be beneficial would be to drop constant bitrate audio and use a lame vbr preset, either or The latter gives better quality than tablet-encode currently offers and has the benefit of a slightly smaller filesize. The 'medium' option would give a significant reduction in filesize while still offering very good quality.

The standard Nokia N810 media player works absolutely fine with these changes.

Here are the differences:

Tablet-encode audio:

Suggested audio:

Tablet-encode video options:

Suggested video options:

The options vrc_buf_size=450:vrc_minrate=0:vrc_maxrate=1000 would seem to be redundant when using lavc as it accepts the specified bitrate as a maximum anyway, and intelligently uses less if the specified rate is not required. The turbo option significantly speeds up the first pass, by over 40% sometimes, and it's fine to leave the option in on the second pass when it will be ignored, no harm done.

In summary I've found that with these changes to the video options and even using lame's preset=standard I get a slightly faster encode and slightly smaller filesize (though both these will vary from file to file) but a huge increase in quality, very noticeable even on the small N810 display. I can't find a downside.