jhead is a command line tool to manipulate EXIF headers of JPEG files. I have used it for months now and it turns out that it is the perfect choice for jobs like that. It is small, fast and easy to use.
A short list what jhead can do:
- Manipulation of EXIF header in several ways.
- Renaming pictures.
- Adjust timestamps in EXIF headers.
- Using other programs during processing.
- Do manipulations according to the camera model used (if model name present in EXIF header).
- And many more…
All those processes can be automated. That makes it easy to deal even with big amounts of images.
A very interesting option is the -cmd<command> option. With this option jhead is able call other programs and use them on the files to be processed. For example, to reduce the quality of several images you can enter:
jhead -cmd "mogrify -quality 80 &i" *.jpg
This line runs jhead on the whole directory tree of photos and reduces the quality of every picture to 80% at the same resolution. You need to install Image Magic because the mogrify program belongs to it. This, of course, works with a lot other image manipulation software as well.
jhead is available for Linux, Windows, OS-X and FreeBSD. It is open source.
Download jhead and get some further information about the program: