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I have done a script to convert recursive .jpg files to another size:
echo $re
mkdir "$re"_tmp
for a in *.jpg ; do convert "$a" -resize $re "$re""_tmp/${a%.*} ["$re"].jpg" ; done
I'd like integrate a multi extension support: png, bmp, etc. better with:
FILEFORMAT="jpg, JPG, png, PNG, bmp, BMP"
any idea to build it?
PS: variable re is the new size 1024x768 (or 800x600, etc)
If I understand right, you want to process files with other extension, instead of only jpg. So you can try:
for a in *.{jpg,JPG,png,PNG,bmp,BMP}; do
printf '%s\n' "$a"
# do your stuff here
done
{...} is bash feature called brace expansion.
#! is for sh. It would be much simpler to do: set -- *.[jJ][pP][gG] *.[bB][mM][pP] *.[pP][nN][gG]; for pic do...;done which would keep the file list in "$@" for multiple process loops as necessary.
*.JPG file) the for loop variable a takes the value of the pattern itself e.g. *.JPG. The matching cases are returned properly. Is there a way suppress returning the non-matching patterns?
Jun 20, 2020 at 14:53
You may use multiple GLOB expressions separated by space:
for a in *.[jJ][pP][gG] \
*.[jJ][pP][eE][gG] \
*.[pP][nN][gG] \
*.[bB][mM][pP]
do
echo "$a" "$re/$a"
done
# or inline
for a in *.[jJ][pP][gG] *.[jJ][pP][eE][gG] *.[pP][nN][gG] *.[bB][mM][pP] ; do echo "$a" "$re/$a"; done
Not sure if it is POSIX compatible, but I believe it is.
echo which is unspecified for arguments containing arbitrary sequences of bytes such as filenames. See also Why is printf better than echo?. Another potential problem is that in POSIX compliant shells (and that is a misfeature from the Bourne shell specified by POSIX), the *.[jJ][pP][gG] expands to *.[jJ][pP][gG] if there's no matching file (so you could end up processing a file by that name).
Jul 26, 2021 at 18:14
for f in $(find . -maxdepth 1 -type f \( -iname '*.bmp' -or -iname '*.png' -or -iname '*.jpeg' -or -iname '*.jpg' \) ) ; do printf "%s\n" "$f" ; done
Jul 26, 2021 at 23:35
-iname is not POSIX. See also Why is looping over find's output bad practice?. In your glob loop, you can always filter out non-matches or non-regular files with an extra [ -f "$a" ] || continue.
Jul 27, 2021 at 5:23
Here is a POSIX complaint variant:
for a in *.jp* *.JP*; do
[ -f "$a" ] || continue
echo "Processing $a"
done
jpg or in upper JPG but not with mixed case.JPG files then the glob wont be expanded and the var a will have *.JP* value. You must filter out it by checking that hte file is exists with the [ -f "$a" ]
*.jpegas well. Apparently someone in the distant past thought it should be*.jpgand this misnomer caught on in a big way... but it seems quite wrong: as if the Joint Photographic Experts Group became the Joint Photographic Group, the implication being that they're not experts!