What is the effect of using TV scale rather than PC scale?

[JimmyBarnes]

Hi

I'm using DVD2AVI v1.76.

I notice there are two values for YUV -> RBG:
PC-scale and TV-scale.

I have come across this before and I know basically that TV scale "uses less colours" than PC-scale. Could someone be more precise than this?

thanks
JB

[MaTTeR]

I've always been intrigued by this also. The only information that I'm aware of is in the D2A dox though:( Personally I've yet to see much of a difference between the two.

[JimmyBarnes]

Originally posted by MaTTeR
I've always been intrigued by this also. The only information that I'm aware of is in the D2A dox though:( Personally I've yet to see much of a difference between the two.

It has a practical use.

Selecting TV-scale results in a 1st Pass size considerably smaller than for PC-scale. I tried it on "Nurse Betty" and got 963/821 MB for PC/TV resp.

What this means is that for the same bitrate and filesize targets, one can use a larger resolution for TV-scale than for PC-scale, for the same GKnot 1st Pass %.

Useful for those movies where one wants to do a 1CD rip but res is getting down around 512x... to get a good GKnot 1st Pass %.

In the bad old days when I was still struggling to control DivX ripsize, I used TV scale in conjunction with resolution to get the final AVI to fit. Now most rips I do at within 1 % of target (using PC-scale) so I am thinking of resurrecting TV-scale and using it to increase the resolution (I like if at all possible to do 1CD rips).

While there seems to be little visible effect of using TV-scale, I would like to know what it actually means tho.

JB

[int 21h]

It only applies if you're in RGB mode.

[MaTTeR]

In that case I won't ever worry about it anymore:D

[stoney]

There are some differences in COlor-visualisation of TVs and PCs. While a PC represents the color black with the RGB-values (0,0,0), TC use (16,16,16) for black. This decreases the dynamic of the image on TVs a bit (and makes movies compress better using MPEG-4 techniques).

Basically it's not that big deal, PC scale gives almost always the better quality.

[dumb13]

Originally posted by stoney
There are some differences in COlor-visualisation of TVs and PCs. While a PC represents the color black with the RGB-values (0,0,0), TC use (16,16,16) for black. This decreases the dynamic of the image on TVs a bit (and makes movies compress better using MPEG-4 techniques).

Basically it's not that big deal, PC scale gives almost always the better quality.

Yes, here is the point.
First, you may rather want to be in YUV mode, in most of the cases, in order to achieve best possible quality. Than, if you need to convert YUV to RGB - depending on your preference - i.e., you prefer watch your movies on TV than on PC, than you select TV. When you select PC, than the dark scenes may become really dark on TV.