Correcting blue hue

[Boulder]

I've got a homemade video with lots of scenes shot in the winter near the time of day when the sun is setting. In my latitude, this means that all colors turn to bluish (which is why I call it "the blue moment" in a day). You can see it easily in the sample clip, the snow should naturally be white.

Is there any convenient way to fix this issue with Avisynth?

http://www.mediafire.com/?sharekey=9b19b691e7eb0ac9d2db6fb9a8902bda

[Guest]

Can't help you because you used some obscure codec for your AVI.

[shoopdabloop]

i was able to open it with DirectShowSource, but i am not familiar with color-altering filters.

[vampiredom]

There is probably a better way (or a YV12-friendly white balance filter you could use), but here is a crude RGB method:

converttorgb(matrix="pc.601")

r = ShowRed().Levels(0,1.0,133,0,255)
g = ShowGreen().Levels(0,1.0,179,0,255)
b = ShowBlue().Levels(0,1.0,255,0,255)

MergeRGB(r,g,b)
converttoyv12(matrix="pc.601")

[Mug Funky]

RGBadjust might help balance the top end, but the blacks will still be off a bit (though video handles this a lot better than film).

YV12 is not really appropriate - in order to get the colours to behave natrually, internal RGB conversions would probably be necessary.

[Boulder]

Can't help you because you used some obscure codec for your AVI.Oh, forgot to mention that I used HuffYUV from ffdshow:o

Unfortunately there is no way to get an RGB capture, the tape is in very bad condition and the capture is pretty much what must be used. A friend of mine has set up a capturing system which consists of a very high quality SVHS deck with a TBC and Edirol's converter which apparently outputs to DV format. The tape was processed by him some years ago.

I'll try the RGBAdjust way. Even a small improvement is much appreciated, because the color balance differences between scenes are quite noticable in the original version.

[scharfis_brain]

you can try to separate the video in R g and b.
after that alter each cannel separately using levels()
then merge them back together

[sh0dan]

Solutions:

1) Teach him to set White balance
2) Greyscale() ;)
3) coloryuv(off_u=-35, off_v=20, cont_v=-50)