match 2 picture with one cropped

[authentic]

Hello

Before loosing long time on a process, I would like to ask you if something is possible.
I've got 2 pictures. 1st one is a big picture, the 2nd one is a cropped version of the one. It's only a part of it, not centered. Is there a way to match the little one on the other with a merge ? I mean is there a plugs or a method to automatically adjust the merge center witha sort of color pixel recongization ?

I don't think it 's possible but maybe someone would know..


Thanks


Vincent

[theajodharan]

Hi , You can do that with a simple math calculation on Merge's X and Y Center.
For example if your BG Image size is 1920 X 1080 and the Cropped FG Size is 431X476 , Just enter
(431/1920)/2 on the X value , and (476/1080)/2 on the Y value.
The image should align perfectly with the BG.

HTH
-T

[authentic]

thanks for help theajodharan but as I said the cropped picture will not necessarely by centered so I'll have to adjut it in x or y position.

[Gringo]

Why don't you just use a Rectangle mask with the Merge instead of pre-cropping?
Or is the picture cropped initially?

[theajodharan]

If you are doing the crop inside Fusion, yep using a rectangle mask is the better option. If the cropping is done externally, you have to do the calculation. To adjust the offset , calculate the offset values using the same method and +/- it from the X and Y position.
But I can't think of a reason to do the cropping externally tho.

[authentic]

In fact the cropped version is not made by the compositor. It's on a background in photoshop. To explain there is first a big environment in psd format with many other information on the picture such like a story board. On this psd, I make a fusion project to separate layers and create some camera moves. Next an artist background will color the environment in phtoshop and then crop it to a certain size to keep only the bg ( so all the text information is deleted). Then I'll have to replace the old big simple environment by the cropped one. It is at this moment that I'l lhave to match the 2 sources. ANd it is at this moment, I would like to know if there could be a sort of automatisation.

[Gringo]

I'm not sure, whether building a comp on an uncropped version with excessive image size is the best way. Although, Fusion 6 should handle it much better with DOD.

Nevertheless, you can match two pictures by eye using extreme zoom in so that you see the pixel grid.
Considering you have to match only position and the resolution is the same, it will be much faster and more precise than any automated algorithm.

[authentic]

Yes Gringo It was what I planned to do. I didin't really expect an automated possibility but I asked anyway, we never know
Thanks anyway for answering

[blacknight]

step 1. Merge the 2 images & select difference in the merge option.
step 2. move the small image until the pattern matches with large image untill the image turns black.

cheers

[authentic]

thanks blacknight that's indeed a great way to see if your adjustment is correct.