How to make an 100% Divx Home Theater / Xvid Home compatible encode?

[kurkosdr]

What settings do i need to do to AutoGK to achieve an 100% Divx Home Theater / Xvid Home compatible encode?

My main concern is that if i set the quality percentage a bit high, like 100%, AutoGK will almost certainly produce a file that exceeds 4096 kbps for more that one second, thus causing some players to freeze or skip. AutoGK even warns you about this by saying that "some compatibility parameters will be ignored".

I ve been told that this can be fixed by enabling two pass encoding (so VBV is enabled), but how to i do that?

Also, can you tell me any other settings i need to do to AutoGK to be Xvid Home compatible?

[hello_hello]

For 100% DivX Home Theatre compatibility you need to select the ESS standalone option in hidden options (Ctrl+F9). If you hit the "About" tab on AutoGK's main page you'll find some info on it in the help files. That and run a 2 pass encode. That's it.

You enable two pass encoding by selecting a target file size rather than selecting a target quality. It's more of a pain as you have to guess the required file size, then watch the result of the compression test. You want it to be around 70 to 75%. AutoGK will do it's best to stop you going over 75% because there's little to be gained in quality (personally I can't really see any difference at all) while the file sizes start to increase by a large amount. If you're much over 75% (it depends on the duration of the video as to what changes AutoGK will make) it might use a sharper matrix or disable some of XviD's compression tricks to try to bring you back to 75%. If you want the maximum quality possible, pick an unrealisticly huge file size, so even after AutoGK makes it's adjustments the resulting output will still be way undersized. That should still give you control over the maximum bitrate and the encode should still be 100% DivX compatible, even if you end up with a huge file.

Before you worry about 100% quality encodes though, try an encode using the 1 pass target quality mode at 100%, then encode the same video again at the default 75%. It might surprise you how hard it is to tell them apart when you check for quality, but the file sizes will be quite different.

The way I make it easier for myself when encoding a lot of video, rather than having to guess at the file sizes for each one, then abort the encode and start again if the compression test result is too far out, I encode everything once using target quality mode at 75%, then I encode everything again using a two pass encode. I look at the file size of each single pass encode and use that file size for the two pass encodes which should ensure each 2 pass encode has a quality of 70 to 75% without AutoGK wanting to make any adjustments. Obviously it takes longer, but I just run all the single pass encodes, come back when they're done and setup the 2 pass encodes, then leave AutoGK to do it's thing again.

There's no way around the "1 pass, no VBR control" problem as to the best of my knowledge it's an XviD limitation. No matter which GUI you use you're going to have to run 2 passes for 100% compatibility. A GUI which doesn't try to make it's own adjustments might be more suitable if you're aiming for 100% quality. One which can run a compression test manually and which lets you setup the Xvid encoder yourself. Off the top of my head, Gordian Knot and HDConvertToX will both run compression tests.
If you want to ensure you're using the same XviD settings as AutoGK does for a DivX compatible encode, run an encode and while it's running open the XviD encoder's configuration dialogue and make a note of all the Xvid settings AutoGK is using. Then you can setup Xvid manually for encoding using another GUI.

Having said all that, does your standalone actually have problems with high bitrates? I know I've owned a couple over the years which have (a scene with lots of rain or snow would almost guarantee they'd stutter if the encode wasn't 100% DivX home theatre compatible) but I've also owned a couple which haven't been bothered by it at all. Still... I generally run 2 pass encodes just to be sure....

[hello_hello]

In case you missed it in the other thread, it's been confirmed that DivX will limit the bitrate when running single pass encoding. So if 2 pass encoding isn't your thing, then using the DivX encoder instead of XviD is probably your only other option.

[Chetwood]

For 100% DivX Home Theatre compatibility you need to select the ESS standalone option in hidden options (Ctrl+F9).
What about the MTM option? So far only one of my standalones came with an ESS chip, all others had Mediatek.

[kurkosdr]

I was hoping that Xvid would have a "two pass constant quantizer" (aka "two pass set quality percentage") mode, but since it doesn't i ll just go with "two pass target size".

[hello_hello]

What about the MTM option? So far only one of my standalones came with an ESS chip, all others had Mediatek.

He was asking about 100% compatibility. To the best of my knowledge the ESS option is the only one 100% compatible with all players. As far as I know the MTK option is exactly the same as the ESS option except for AutoGK using custom matrices instead of the standard h263/mpeg matrices. There's probably not a lot of them around these days, but apparently some players don't like custom matrices, presumably ones with ESS chipsets.

Personally, I prefer the standard matrices anyway. I haven't done a lot of comparing so maybe the custom matrices produce better results at lower bitrates or lower quality settings, but I always aim for 75% quality (or Q2.7) and for that I prefer the standard matrix.

[hello_hello]

I was hoping that Xvid would have a "two pass constant quantizer" (aka "two pass set quality percentage") mode, but since it doesn't i ll just go with "two pass target size".

You're welcome.
Oh sorry, after typing all that info I assumed you'd said thank you.