Legacy ImageMagick Discussions Archive

FYI: Maybe I'm missing something, but can't I just combine the scale to square pixels and user scaling into one step? It looks like it's working perfectly for me this way. I wrote a program (in C++/Qt) that calculates the smallest scale factors that after a given rotation a 640x480 rectangle will ...

Quick followup question: For the SRT, in order to define the x and y scale components separately, you need to use the form of SRT with at least 5 parameters: X,Y ScaleX,ScaleY Angle. I would like the X and Y to be set to the center of the image automatically, what would the formula for that be ...

It's working perfectly now. Here's the final command for those interested. I wrote a program to calculate the scale values (here .604 and .453) for a given rotation (here 0.8), and everything else was straightforward: convert in.tga -background white -virtual-pixel background -set option:distort ...

I'm thinking now the SRT can handle this for me perfectly. I didn't realize I could do a scale that had different x and y components. So I can calculate the x and y scale factors such that my original 1920x1080 image will get scaled down to something that when rotated will yield a 640x480 center ...

Just for clarity's sake, let me explain the whole process. 1) I start with thousands of images for each video that have been extracted from the video with ffmpeg. 2) These images all have a slight rotational error that I want to correct before turning back into video. 3) The original images are ...

Hey wow, this is great! I knew there would be a formula to calculate this, but my trig/geometry was too rusty to figure it out! I had just written a program to calculate it iteratively, but the direct formula is much better. Basically what I'm doing is like your new example, my videos were taken ...

I'd like to have IM automatically figure out the best crop, since I'm converting about 50 videos, so I'd rather not have to calculate everything by hand. The rotate command will be the same for each video, so I guess if I have to, I can do the 50 calculations... Right now the fastest command I've ...

To put the problem graphically (see link), if the white box represents my original image that has been rotated, IM is returning the blue box as the viewport and I want the red box as the viewport. Any idea of how to do this???

http://grauman.com/box.png

Thanks!

Josh

FMW42, The -distort SRT did indeed help! The problem I'm having now involves setting the viewport correctly. I tried the method for the Centered Square Crop, but it creates a viewport that includes the entire rotated image (which has corners of distortion), whereas I would like the viewport set ...

mogrify and convert ended up taking the same amount of time...

Thanks, I'm recompiling as Q8. OpenMP compiled in as well. We'll see how much that helps. If anyone knows any other tricks, please let me know. Thanks!

I had just downloaded and installed latest IM. Here is my version... Version: ImageMagick 6.7.0-2 2011-06-01 Q16 http://www.imagemagick.org Copyright: Copyright (C) 1999-2011 ImageMagick Studio LLC Features: OpenMP What is Q16 and Q8 IM? I'm on Linux and have multiple cores (just ordered a 4-core ...

Hello, I need to perform the following operation thousands of times, and so want to know if there is any way I can speed it up. Is this operation multi-threaded? Any compile settings that will help significantly? Other tricks/tips? Thanks! convert image1.tga -rotate 1.2 -crop '1000x1000+20+20 ...

Thanks! Works like a charm.

Hello all, I'm trying to figure out how to create text with a completely transparent background, where the text itself has some transparency as well. I'd like text that is 20% transparent on a completely transparent background. The following achieves what I want (minus the transparent text). Can ...