[SOLVED!] On an Android phone is there an open source method of compressing files?
I have to submit a document for employment and they want my passport but my passport photo is 5.49 MB and they say you can't upload anything more than 5 MB. How can I shrink that file on my android phone without paying some service?
Dear OP, please edit the post title and insert [Solved] to prevent a 1000 more answers in the coming 5 years in this thread (and in the new comments time line), thank you :)
Btw, media formats are not really compressible (e.g. zip, 7z, gz, etc.), because they are already compressed by specialized algorithms (png, jpg, avif, etc.).
You're looking for something to export the image at a lower resolution (resize) rather than something to compress the image. Any open source gallery/image editing app should be able to do this.
One example would be "image toolbox" on FDroid. I've not used it but it seems to have the feature you need
I've been using Image Shrink on Android for the better part of a decade. It works flawlessly for exactly this situation.
I set the resize options to maximum dimension of 1600px.
Then the workflow is share from any app (like the Gallery) to Image Shrink, it resizes the photo(s), then reopens the share prompt to share on to wherever you're trying to send them (like an email client).
You can also choose Image Shrink in the file picker to do it in reverse - select the files in the app you want, and they get resized on the way in.
I guess you can install termux and in termux install imagemagick. Then use the mogrify tool from imagemagick to lower the image resolution. For example (Make sure to make a backup!) :
Any photo editor will do. Just load it in and export as JPEG or smaller resolution.
On f-droid:
Pocket Paint is crashy for me, but it gets the job done.
Imagepipe has a bit clunky interface but just to load and export it works fine. Its primary advertised purpose is to remove metadata from photos, so not a bad thing to have on hand anyway.