Convert JPG to JFIF

[jorge]

Hi all

I'm totally new to exiftool and I don't really get how to convert a file from jpeg to jfif. I undertand that I need to change some header metadata but I don't know how to do it... forgive my ignorance 

Please let me know how to do it.

[Phil Harvey]

A JFIF image is just a JPEG with a JFIF header.  To add a JFIF header, write the JFIF tags, like this:

exiftool -jfif:xresolution=72 -jfif:yresolution=72 image.jpg

- Phil

[jorge]

Just what I needed. Thanks a bunch