Legacy ImageMagick Discussions Archive

Thanks snibgo/fmw42! I misunderstood the IM docs for SRT: "If no control point is given, the exact center of the input source image is used". No control point is indeed NOT similar to control point 0,0. If I use the coordinates of the center of the image for the rotation point and add that...

Actually, 0,0 is the center, any other value introduces an offset. SRT with 6 arguments (X,Y Scale Angle NewX,NewY) first scales (but yours doesn't), then rotates about X,Y, then translates from X,Y to NewX,NewY. So your rotate is about (0,0), the top-left corner. Perhaps you'd prefer to rotate abou...

Hi fmw42, The zelda picture is probably too small to see the effect. I am using 2826x2112px. -virtual-pixel none does not make any difference. I get virtually the same result using IM -distort SRT and GIMP for 20 degree rotation. There is a nominal 0.5 pixel offset unless you use image coordinates i...

Hi Snibgo, Thanks for your input. The order of rotation and translation makes no difference. The units do not seem to be the problem: the rotation is correct, the problem is in the translation. I tried to increase the angle (great idea!) and that showed that I mistakenly thought that the scaling wen...

Hi, I have written a python script for Gimp to visually align two images together using layer rotation and translation. I want to use the values found in Gimp to batch-process a set of similar images in IM, using -distort SRT. The SRT values for Gimp produce slightly different results in IM. If the ...

Found it! Checked it out and it works 100% OK! Thanks everyone, GREAT JOB!

Is there any progress on the new beta release? Thanks.

Anthony, Thanks for your effort. I have done some further testing. The thing I am trying to do is to align 25 images with two "jittering" origin points to line up with two chosen destination points. I have made 5 runs with the set of 25 x 2 points, making minor changes to only one destinat...

Are you using Ubuntu? If so, what version?

NEW RESULTS:
using literally the same code (including the koala.png imagefile) from the second example in http://www.imagemagick.org/Usage/distor ... rol_points also produces a black image.

The first example works OK...

The thing I need is the second example in http://www.imagemagick.org/Usage/distorts/#control_points (aligning two points on two other points) I am using the exact code as described in the example, resulting sometimes in black images, as described in my original post. NEW RESULTS: If I add a third co...

Thanks for your input. The Affine method should work with two control points. See http://www.imagemagick.org/Usage/distor ... rol_points.

I cannot see how to use SRT with two controlpoints. AFAIK rotation must always be there. This was my main reason to switch to Affine.

I want to do a distortion with two controlpoints on a 2816x2112 pixel image. convert 001.jpg -distort Affine "369.5,1060.5 700,1100 2405.5,1077.5 2000,1100" 002.jpg - image is all black :shock: convert 001.jpg -distort Affine "368.5,1060.5 700,1100 2405.5,1077.5 2000,1100" 002.jp...