Linux offers a very simple way of converting multiple image files to PDF.
For simplicity, it’s best to place all these image files into a single folder.
We can then use the convert command.
To convert all image files and put them into a single multi-page PDF, use:
convert *.jpg output.pdf
In case some of the image files have portrait orientation and some landscape orientation, use the -auto-orient flag:
convert *.jpg -auto-orient output.pdf
To convert all image files into separate PDF files, create a loop:
for file in *.png; do convert "$file" "$file".pdf; done
This will, however, keep the original extension as well, so the final filename will be something like imagefile.png.pdf.
To remove the previous extension during conversion, use:
for file in *.png; do convert "$file" "${file:0:-4}".pdf; done