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  • Cut first 16 characters of all filenames in directory?

    From Tuxedo@21:1/5 to All on Sun Jul 7 07:09:01 2019
    Hello,

    I use a script to rename image files copied from a camera to include the
    EXIF generated date into each filename.

    The filenames originally appear as follows::

    DSC00071.JPG
    DSC00075.JPG
    DSC00086.JPG
    DSC00093.JPG
    DSC00116.JPG
    DSC00133.JPG

    After running the script, they appear as:

    20190531_083305_DSC00071.jpg
    20190531_083429_DSC00075.jpg
    20190531_092253_DSC00086.jpg
    20190531_092643_DSC00093.jpg
    20190531_093211_DSC00116.jpg
    20190531_095200_DSC00133.jpg

    Nothing wrong with the procedure, it works great, but sometimes I run it
    twice on a batch of files by mistake, ending up with the following:

    20190531_083305_20190531_083305_DSC00071.jpg 20190531_083429_20190531_083429_DSC00075.jpg 20190531_092253_20190531_092253_DSC00086.jpg 20190531_092643_20190531_092643_DSC00093.jpg 20190531_093211_20190531_093211_DSC00116.jpg 20190531_095200_20190531_095200_DSC00133.jpg

    (... plus thousands more.)

    Whenever it happens I erroneously prepend the date string and underscores to previously processed files, i.e. the 16 characters of each filename as
    above.

    How can I remove the 16 characters in each filename, by renaming all files
    in the current working directory to retain only the last 28 last characters?

    But so I don't rename filenames that may still exist in the same directory which are still correctly named, the procedure should apply only on files
    which are exactly 44 characters long as the wrongly named files in this
    example are.

    Many thanks for any ideas and solutions.

    Tuxedo

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  • From Keith Thompson@21:1/5 to Tuxedo on Sun Jul 7 13:47:59 2019
    Tuxedo <[email protected]> writes:
    Hello,

    I use a script to rename image files copied from a camera to include the
    EXIF generated date into each filename.
    [snip]

    This was separately posted (not cross-posted) to comp.unix.shell and is
    being discussed there.

    If more than one newsgroup is relevant, please post a single article to
    both groups so the discussion doesn't fragment.

    --
    Keith Thompson (The_Other_Keith) [email protected] <http://www.ghoti.net/~kst> Will write code for food.
    void Void(void) { Void(); } /* The recursive call of the void */

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Helmut Waitzmann@21:1/5 to All on Sun Jul 7 22:43:08 2019
    Tuxedo <[email protected]>:

    I use a script to rename image files copied from a camera to include the >EXIF generated date into each filename.

    The filenames originally appear as follows::

    DSC00071.JPG
    DSC00075.JPG
    DSC00086.JPG
    DSC00093.JPG
    DSC00116.JPG
    DSC00133.JPG

    After running the script, they appear as:

    20190531_083305_DSC00071.jpg
    20190531_083429_DSC00075.jpg
    20190531_092253_DSC00086.jpg
    20190531_092643_DSC00093.jpg
    20190531_093211_DSC00116.jpg
    20190531_095200_DSC00133.jpg

    Nothing wrong with the procedure, it works great, but sometimes I run it >twice on a batch of files by mistake, ending up with the following:

    20190531_083305_20190531_083305_DSC00071.jpg >20190531_083429_20190531_083429_DSC00075.jpg >20190531_092253_20190531_092253_DSC00086.jpg >20190531_092643_20190531_092643_DSC00093.jpg >20190531_093211_20190531_093211_DSC00116.jpg >20190531_095200_20190531_095200_DSC00133.jpg

    (... plus thousands more.)

    Whenever it happens I erroneously prepend the date string and underscores to >previously processed files, i.e. the 16 characters of each filename as >above.


    … and if by mistake, the script is run once more, there will be file
    names containing a triple of identical date info…

    How can I remove the 16 characters in each filename, by renaming all files >in the current working directory to retain only the last 28 last characters?

    But so I don't rename filenames that may still exist in the same directory >which are still correctly named, the procedure should apply only on files >which are exactly 44 characters long as the wrongly named files in this >example are.


    I suggest a slightly different solution:

    For each filename, check, whether it starts with a sequence of at
    least two identical patterns each consisting of 8 digits, one
    underscore, 6 digits and one underscore. If that's the case,
    strip all but one of these patterns from the start of the
    filename.

    (
    for f in *.jpg
    do
    if sequence="$(
    expr ' '"$f" : \
    ' \(\([[:digit:]]\{8,\}_[[:digit:]]\{6,\}_\)\2\{1,\}\)'
    )"
    then
    date_info="${sequence%${sequence#????????_??????_}}" &&
    renamed_f="${date_info}${f#${sequence}}" &&
    mv -i -- "$f" "$renamed_f"
    fi
    done
    )

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    * Origin: fsxNet Usenet Gateway (21:1/5)