Query with Image Quality Priority

[makaone]

I just need a little help , I don't understand the guide to this tab.

The guide says that the "smaller the value the more bits will be allocated to complex parts.

It then says that " If scenes with Low amount of action look bad then you should increase the value ".

I don't really understand that , to me that means that poor quality means i should " Decrease " the value as this would improve the quality of the picture.



I just thought that the more bits you added to a scene the better it got , but as i don't know the answer to this i would hope one of you fine people out ther could kelp explain it to me a bit better.

Just trying to understand how and why things work.

Makaone

[emilius256]

With a lower value fast scenes gets more bits and may look better but scenes with low action get less bits so it may look bad.
So, if you got good fast action scenes but bad low action scenes you have to increase the value, if you have good low action scenes but bad fast action scenes you have to decrease the value.
Normally i left to default value, 17, and have good results.

Hope i explain well.
bye.

[Kedirekin]

Actually, I think this setting controls allocation of bits within single frames.

For example, you have a frame where the left side has lots of fine detail, and the right side is smooth and flat (a wall, say). With a low setting, more bits will be allocated to the detail on the left side. This will decrease mosquito noise, but might result in the right side suffering from macroblock quantization (what I call moving posterization). With a high setting, fewer bits will be allocated to the detail, with consequent increase in mosquito noise and decrease in posterization effect.

My rule of thumb - the DVD2SVCD default setting of 17 is good for hollywood movies that are bright most of the way through. If I know the movie has a lot of dark scenes (Planet of the Apes, Perfect Storm), or if it is anime/animation (which usually has lots of flat color areas) I increase the setting to between 25 and 40 (pretty much based on whim).

[makaone]

Thanks alot for the insight as i now think i've got the gist of it.

I'm just glad that there are people out there on this forum that don't mind spending time answering these sorts of questions.

Thanks again.

Makaone

[markrb]

@Kedirekin have you ever tried lowering the number? I have made some encodes at 15, but I have never done a direct compare.
I am about burned out with testing, but I might try messing around with this too.

Mark

[Kedirekin]

I've never tried lowering it below 17. Even at 17, I often get the moving-posterization effect (in the openings and the closing credits if not elsewhere), and I find the effect much more objectionable than mosquito noise.

In fact, I'm tending to use 25 as my default more and more.