Legacy ImageMagick Discussions Archive

Thanks very much indeed.
Yes, definitely would have been out of date as I harvested that from a 2008 post on this board.

I'm using a Python library that creates pngs, but once in a blue moon, generates a set of pngs that are essentially just transparent. I have no idea why and it's a rare enough event not to want to bother investigating. The images are intended for social media, and I'd like to be able to test for ...

Ah that's perfect!
I'll be resizing everything on the fly anyway (it's for another bot to generate 'random' postcard images).
One day this stuff will have sunk in enough that I don't have to ask, but I expect the planet will have burned to a crisp by then anyway.

thanks so much.

weird.
i rightclick and save and they come down as pngs

here's a filebin link for a zipfile: https://filebin.net/uwmxh83aejt8v1l0

I've just downloaded them from imagebin to check, and they are pngs: identify sees them as pngs, and the first three bytes of each are "PNG"

Maybe there's something your browser is doing?

There are probably half a dozen different ways to do what you want in bash, and it's not entirely clear from your post what all the details of your situation are. If you are going to be working in bash in the future, you need to learn it properly. It is a much more powerful and flexible shell than ...

ImageMagick 6.9.10-14 Q16 i686 GNU/Linux, 32 bit Delegates (built-in): bzlib fontconfig freetype jbig jng jpeg lcms lqr lzma pangocairo png tiff wmf x xml zlib *Still* can't get my head around transparency, backgrounds & foregrounds and compositing ... :? I'm pretty sure this will turn out to be ...

Does it appear in the file name or path to the file? What happens afterwards? Does it create an output? Can you find the file it is failing on and if you run it again does it fail? Do you have enough space in your /tmp file or whatever file is being used by MAGICK_TEMPORARY_PATH? in order: No, it ...

Version: ImageMagick 6.9.10-14 Q16 i686 2018-11-10 Features: Cipher DPC OpenMP Delegates (built-in): bzlib fontconfig freetype jbig jng jpeg lcms lqr lzma pangocairo png tiff wmf x xml zlib Linux 32bit, 4GB RAM. I get this error intermittently. Can't reproduce it to order. "convert: no decode ...

I would simply recommend convert image -channel a -separate -scale 1x1! -format "[fx:mean]\n" info: If it is full transparency, you get 0 and fully opaque you get 1 and partially transparent is some value in-between. Perfect ready-made answer to a problem I just tripped over today ... with the tiny ...

ADDENDUM Just a quick note to say that I recently made a small mod to the script that has made it work even better for my purposes. By design, the text is always positioned in (roughly) the top one-third of the image, but for some images, the text tone (lighter or darker) was not quite right - for ...

Damn you for pointing out my spectacular stupidity.

UPDATE: Let this question be a dire warning to she or he who would post a query without first checking every obvious cause of an apparent error Version: ImageMagick 6.9.10-14 Q16 i686 2018-11-10 Features: Cipher DPC OpenMP Delegates (built-in): bzlib fontconfig freetype jbig jng jpeg lcms lqr lzma ...

Thanks again.
I'm set to go now.

Your IM pages at snigbo.com are amazing, btw, but I expect I'm not the first to tell you that ...

Ah thank you both! I've been using IM for years and years, but just for odds and bits of trimming, cropping and montaging, and have never really wanted or needed to explore it further. @snigbo your script works beautifully, it'll probably be exactly what I use. The only question that pops up for me ...