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Rename .JPG to .jpg recursively

Terminal - Rename .JPG to .jpg recursively
find /path/to/images -name '*.JPG' -exec bash -c 'mv "$1" "${1/%.JPG/.jpg}"' -- {} \;
2010-01-07 15:41:17
User: sorpigal
Functions: bash find
7
Rename .JPG to .jpg recursively

Recursively rename .JPG to .jpg using standard find and mv. It's generally better to use a standard tool if doing so is not much more difficult.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
find /path/to/images -name '*.JPG' -exec rename "s/.JPG/.jpg/g" \{\} \;
2010-01-02 19:12:37
User: renich
Functions: find rename
Tags: find rename
8

This command is useful for renaming a clipart, pic gallery or your photo collection. It will only change the big caps to small ones (on the extension).

Know a better way?

If you can do better, submit your command here.

What others think

find /path/to/images -name '*.jpg' -exec rename.ul .JPG .jpg {} +

rename.ul is the util-linux rename command, widely available on linux systems, possibly named just 'rename' if not overridden by perl rename (prename). Also here I use the + form of -exec instead of \; so that find will launch rename.ul on many file names at once, using many fewer process spawns. With -exec bash -c mv ... you launch a shell process which launches a mv process just to rename one file. It works, but for performance, you'd be much better off writing a shell script, which is a very standard tool.

Comment by bwoodacre 346 weeks ago

Thanks sorpigal.

This did exactly what I needed it to. I tried the other command but it failed. Maybe I had a typo.

@ bwoodacre. I should have totally used + instead of \; Dooh!

Comment by Xinerama 302 weeks and 4 days ago

Using the "-exec" option of "find" is not a good technique. Basically while it is running a command "find" is waiting, and not 'searching' for the next file.

This is why piping the output of "find" into "xargs" is a better idea. The filename gets cached by the pipeline ready for "xargs" to use when ready, while "find" continues to search.

See find -exec vs xargs

http://www.sunmanagers.org/pipermail/summaries/2005-March/006255.html

Also look at commands like "mv_perl" whcih can rename multiple files in the one command. You can have "xargs" feed lots of files to each command, or just one one command per directory.

Comment by anthony 302 weeks and 4 days ago

Your point of view

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