Match VHS colors to DVD reference?

[Brad]

#1 is DVD, #2 is my attempt in Avisynth, #3 is automagical tool: Color Correct v1.4 by "DrDre" on the Original Trilogy forum. (I haven't checked for new updates in the past 6 months.) [EDIT: #4 is ColourLike.]



Red certainly looks closer in the DrDre result than my attempt, but the grass and shrubs have become the same color.

Any suggestions for improvement?

[flashandpan007]

Ok, what do you wanna do? What should be the result?

[johnmeyer]

I too am not clear on what you want to do. Also, your two corrected results have somehow become blurred, as though two frames were blended. Or, are you saying that the two corrected pics are from a VHS tape? If so, then I am even more unsure of what you are trying to do. If you somehow want to use this as a way of calibrating your VHS capture chain, then this is most definitely the wrong way to do it. Instead, find a tape that contains color bars at the beginning or end of the tape and use that. While each tape may be somewhat different, this would at least give you a starting point and would do so by using a known reference (i.e., the color bars).

[Brad]

I have recordings of TV shows with shots that were excised from the DVD release. The surrounding scenes exist in both to compare and match.

The Spider-Man clip is something else, but the idea is the same: the DVD has the correct colors and the VHS capture does not. I want to change the VHS to look as much like the DVD as possible.

If you somehow want to use this as a way of calibrating your VHS capture chain, then this is most definitely the wrong way to do it. Instead, find a tape that contains color bars at the beginning or end of the tape and use that. While each tape may be somewhat different, this would at least give you a starting point and would do so by using a known reference (i.e., the color bars).

What readily-available tapes include color bars? The closest I've come across is a grey screen with audio tone at the end of a tape. This wouldn't help for the TV recordings, at any rate.

[TimA-C]

Could you record something from a DVD without copy protection onto your VHS Recorder and then capture your VHS recording. That way you'll have your own reference original to compare with your capture. You could probably generate (or download) your own test patterns and burn to DVD for subsequent test captures.

[JVRaines]

Your red looks a little too hot on the suit.

[jagabo]

Try ColourLike().

http://forum.doom9.org/showthread.php?t=96308

First run:

dvd = MPEG2Source("Spider-Man FS DVD.d2v").Trim(3,0)
vhs = AVISource("Spider-Man - JVC HM-DH5U (EDIT, 60p) [reinterlaced].avi").AssumeTFF().ConvertToYV24().AddBorders(1,0,0,0,color_white).Crop(0,0,-1,-0).ConvertToYV12()

dvd.Crop(16,16,-16,-16).WriteHistogram("dvd hist 1.txt", 1) # cropping to ignore black borders, head switching noise, etc.
vhs.Crop(16,16,-16,-16).WriteHistogram("vhs hist 1.txt", 1)

#vhs.colourlike("vhs hist 1.txt", "dvd hist 1.txt")

Then run:

dvd = MPEG2Source("Spider-Man FS DVD.d2v").Trim(3,0)
vhs = AVISource("Spider-Man - JVC HM-DH5U (EDIT, 60p) [reinterlaced].avi").AssumeTFF().ConvertToYV24().AddBorders(1,0,0,0,color_white).Crop(0,0,-1,-0).ConvertToYV12()

#dvd.Crop(16,16,-16,-16).WriteHistogram("dvd hist 1.txt", 1) # cropping to ignore black borders, head switching noise, etc.
#vhs.Crop(16,16,-16,-16).WriteHistogram("vhs hist 1.txt", 1)

vhs.colourlike("vhs hist 1.txt", "dvd hist 1.txt")

[johnmeyer]

I have recordings of TV shows with shots that were excised from the DVD release. The surrounding scenes exist in both to compare and match. The Spider-Man clip is something else, but the idea is the same: the DVD has the correct colors and the VHS capture does not. I want to change the VHS to look as much like the DVD as possible.

OK, I should have thought of that because I've had to do the same thing myself.

Now that I understand this, the usual way to handle this is to use one of the color correcting options in your NLE. I use Sony Vegas, and I can click on a reference color, and then click on a pixel in the video I want to match, and Vegas will make that pixel the same color as the original.

You should try to get the histogram (or waveform) of the two clips adjusted to match before you do the color correction.

Also, as I've said in other posts, it is a lot easier to do color adjustments in an interactive environment, and using tools that were designed specifically for the purpose. AVISynth is not the first tool I would think of using for this purpose.

What readily-available tapes include color bars? The closest I've come across is a grey screen with audio tone at the end of a tape. This wouldn't help for the TV recordings, at any rate.

Well the operative phrase is obviously "readily available." First of all, there are no longer any readily available VHS tapes, since no one sells them any more. The ones I have which contain color bars are generally those that were produced for training and corporate purposes. In the old days the video market was sometimes divided into the consumer, industrial, and broadcast markets. It is the industrial market that usually included color bars so the "roll about" conference room equipment could be calibrated a little bit before the presentation was started.

[Brad]

Try ColourLike().

Thanks for the suggestion and script. I've added the result to the first post. To me, at least, the DrDre version looks closer.

the usual way to handle this is to use one of the color correcting options in your NLE. I use Sony Vegas, and I can click on a reference color, and then click on a pixel in the video I want to match, and Vegas will make that pixel the same color as the original.

I'll have to give that a try with the TV show recording.