[VCDImager] Re: Muddy quality and a green line

[Andrew Stevens]

Hi,

Sorry about the delay responding - the weather's been superb so I've been out 
touring on my shiny new Motorbike ;-).

<cheeky>
For all you young indoor mjpeg and vcd coders: you gotta try the great 
outdoors sometime too.   Recommended occasional Coding alterantives: 
ridge-running a Sail-plane in the mountains, riding a nice fast motor-bike up 
and down Alpine roads.  Diving is pretty good too.

Sadly only Diving is good therapy if typing gives you sore or numb fingers :-(

O.k.  o.k. so I'm feeling guilty at lagging behind you young thrusting folk 
and trying to slow you down so I can resync ...
</cheeky>

> > When I watch the SVCD on TV it is very muddy. Everything is darker than
> > it should be. The shadows lose their detail. The colors lose their
> > saturation. And there is also a green line on the right side of the
> > screen. What's going on? Any ideas?

This sounds like a gamma problem.   Unfortunately I don't know DV so I can't 
give you an exact culprit.  The MPEG encoding chain expects "raw" (non gamma 
corrected) video.  My guess is that the DV library in lav2yuv is gamma 
correcting (this makes dark stuff darker relative to light stuff).  Thus 
since the MPEG player is also doing gamma correction you're getting  a double 
gamma correction which is not good for image quality ;-).  Or some variation 
on this theme...

Andrew