Hello guest, if you like this forum, why don't you register? https://forum.fanres.com/member.php?action=register (December 14, 2021) x


Using the colour info from one source and the detail from another.

27 Replies, 20289 Views

Could anyone post a tutorial about how to overlay 2 sources, using the detail from one and the colour info from aother?

I've heard mention of it before but I'm not sure how to go about it. Is it the chroma from one and the luma from another?

Thanks for any light folks can shed on this.
To use luma from a source, and chroma for another, the two sources should be spatially aligned; but it's an almost impossible situation - no problems with eventual temporal difference, it is still possible to repeat/delete eventual frames.
Of course, it's still possible to upscale one source to have the same resolution of the other, but it's very difficult that all the frames will align perfectly with just one upscale setting...

In the eventual case you have two perfect spatially aligned sources - let's say, one with "wrong" color grading, the other with too much edge enhancement, it's possible to take the luma from the first, the chroma from the second and align them - really simple to do with avisynth; but there is a really remote probability to have those...

Usually, what really happens is to use the luma of a good quality source - like BD for example - that has a "wrong" color grading, and use the chroma of another source - like DVD - as COLOR REFERENCE; what does it mean?

For example, for my "Halloween" project, I took the luma from the 35th Anniversay BD, and the 1999 THX DVD was used as color reference; an avisynth script "extracted" somehow the color informations from the DVD, and applied them to the BD; this does not always a perfect job (at least, using my script), but with this movie, it made a wonderful job, leaving just few shots not perfectly rendered and I just fixed them manually.

Another way is to adjust the chroma of a source to look alike another source; this is a painful job, because it's almost impossible to find a single setting for the whole movie; at the contrary, any scene (and sometimes any shot) should be fixed using different settings... with this method, a very well optimized monitor and a LOT of time and patience, it is possible to get a final product with a perfectly matched color grading!
Sadly my projects are lost due to an HDD crash... Sad
Fundamental Collection | Vimeo channel | My blog
Thanks for all the useful info. Is is possible to do in After Effects? I don't tend to use avisynth.
I think so, but, because I'm an old dinosaur who likes to use ancient software Big Grin frankly I don't know for sure... hope some After Effect user could step in to answer your question!
Sadly my projects are lost due to an HDD crash... Sad
Fundamental Collection | Vimeo channel | My blog
Could you let me know the pocedure for using 2 aligned sources in avisynth? If I can get the 2 sources to line up completely in my editor and export them, I should just need to process the clips through avisynth as you described, right?

So what exactly do you need to do to get the parts from each source that you want and render them as one?

Cheers
Here you are the avisynth filters to use: http://avisynth.nl/index.php/Merge

Post here your test results!
Sadly my projects are lost due to an HDD crash... Sad
Fundamental Collection | Vimeo channel | My blog
(2015-01-29, 02:59 PM)spoRv Wrote: Here you are the avisynth filters to use: http://avisynth.nl/index.php/Merge

Post here your test results!

Cheers for the link. Gonna have to get my head around this avisynth thig before I can give it a try.
Ok, so I have 2 clips spatially aligned, so I just need to get the luma/ chroma overlayed. Here's the script I've tried

AVISource("Sequence 01.avi")+AVISource("Sequence 01_1.avi")
mergechroma(mergechroma(source1,source2)

I'm getting an error: I don't know what "source 1" means.

Any idea what I'm doing wrong?
Try this:

Code:
setmemorymax(1024) # set this from 1/2 to 2/3 of your RAM (in MB)
temp1=AVISource("Sequence 01.avi")
temp2=AVISource("Sequence 01_1.avi")
source1=mergechroma(source1,source2)
source2=AVISource("Sequence 02.avi")
mergechroma(source1,source2)
Sadly my projects are lost due to an HDD crash... Sad
Fundamental Collection | Vimeo channel | My blog
(2015-05-23, 12:46 PM)spoRv Wrote: Try this:


Code:
setmemorymax(1024) # set this from 1/2 to 2/3 of your RAM (in MB)
temp1=AVISource("Sequence 01.avi")
temp2=AVISource("Sequence 01_1.avi")
source1=mergechroma(source1,source2)
source2=AVISource("Sequence 02.avi")
mergechroma(source1,source2)

Thanks for the reply, but I get the same "I don't know what "source 1" means" when using this script.

Possibly Related Threads…
Thread Author Replies Views Last Post
  Colour Correction Issues alleycat 3 1,233 2020-04-05, 07:03 PM
Last Post: alleycat
  Interview with Dale Grahn, Colour Timer zoidberg 6 3,265 2018-06-05, 07:04 PM
Last Post: captainsolo



Users browsing this thread: 1 Guest(s)