Why is 8000 max bitrate?

[kallekill]

Why can't you choose more than 8000 as max bitrate in tmpg?

[ArdenDag]

Have you ever seen a DVD with that high a bitrate?

BTW, max bitrate for DivX codec is 10000, not much higher

[kallekill]

Many DVD's have a max bitrate of 9700. Most Hollywood movies use 9700 as max bitrate.

I thought max bitrate for divx was 6000

[bb]

ArdenDag, you compare apples to pears. DivX (5.0.2) is a low-bitrate codec; to get comparable results using MPEG-2 you need much higher bitrates.

The 6000 kbps limit is valid for the old DivX ;-) 3.11a only.

E.g. for DV home video conversion max. possible DVD bitrate would be desireable.

bb

[Tr0LL]

You have to select the unlock template in order to set the bitrate higher than 8000. That's all. Then you can set it to 9700 if you want.

[kallekill]

Are there any known problems of using a bitrate higher than 8000 or why have they choose not to include a higher bitrate with the normal templates?

[lancer]

I would think that 9700 would only be sustainable for very short periods.

max speeds are usually quoted from burst speeds not sustained data transfer rate. if something was sustained at max for a while it would probably stutter all over the place.

[kallekill]

I've also heard that you shouldn't use a CBR of more than 8000 but most Hollywood dvd's are encoded using VBR and a max bitrate of 9700 so I guess that it is up to the encoder to see to that the bitrate isn't obove 8000 for a long period of time.

[adam]

Originally posted by kallekill
Why can't you choose more than 8000 as max bitrate in tmpg?

Because most people who use TMPGenc don't own DVD pressers.

Many people have reported problems with dvd-r/w, +r/w playback when bitrate exceeds ~8mb's, even though the DVD standard supports it. I assume this is why the author of TMPGenc selected this value. Alot of commercial DVDs will have sustained periods above 9mb's, but thats a luxury that you don't always have with recordable dvd. Depending on your hardware (burner and player) and your media your mileage will vary but pressed media will always be more compatible than burnt media.

[GMH]

... don't forget that the bitrate also has to take into account the audio and subtitle streams that are also present in the final VOB file. All of these will rob the available bandwidth.