How to slice and put them back together

Software G'MIC
1

G’Mic newbie here.

I have a set of images, a timelapse, that spans a couple of hours.

I’ve been using imagemagick to slice the images and put them back into 1 image.

The problem, that I have, is that it assembles as slices

burrard-bridge-1
burrard-bridge-1900×602 70.5 KB

I’d like to have smooth transitions between each slice.

I am looking at G’MIC and the slice command it says:

slices
Arguments:

    z0[%],_z1[%]

Description:
Keep only specified slices of selected images.
  1. what is z0? what is _z1?
  2. how do I assemble?
  3. can I make a “smooth” merging of the slices?

Thanks

2 Likes
2

In G’MIC, the word slice is used in the context of 3D volumetric images, i.e. where an image has a width (size along the x-axis), a height (size along the y-axis) and a depth (size along the z-axis).
In that case, a slice J correspond to the 2D image defined by J(x,y) = I(x,y,z), where z is the slice number (going from 0 to depth - 1).

So, that’s completely different from what you are looking for.

3

Can you point me in the direction to create slices and reassemble them?

Thanks

4

Use split x,16 , where 16 is the number of blocs you want at the end.

$ gmic sp lena split x,16

Then, to reassemble:

$ gmic sp lena split x,16 append x
5

Thank you for taking the time to help me.

6

Perhaps you should look at enblend for the transitions:
http://enblend.sourceforge.net/

7

Try using Hugin to smooth transitions betweeen slices

the Image ref is

b
b8288×5520 10.2 MB

slice the ref image using Imagemagick ( 4 vertical slices )

convert b.jpg -crop 4x1@ +repage output%02d.jpg

Sélection_001

Then change EV for each slice using Darktable ( -2EV, - 1EV, 0.EV, +1EV)
Sélection_002

Assemble the slices using Hugin

Hugin Assemblage 4 images
Hugin Assemblage 4 images1004×741 231 KB

then use Hugin to smooth transition between slices

the result without any optimizations

output00_2k - output03_2k_2k
output00_2k - output03_2k_2k2000×1478 711 KB

8

Wow :grinning:

This is will become my project for the end of the year (right now, we are moving).

Just a quick question, do the slices need some overlap?

Thank you very much

9

No, the slices don’t need some overlap
:slight_smile: