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Commands tagged jpeg

Commands tagged jpeg from sorted by
Terminal - Commands tagged jpeg - 7 results
find . -iname '*jpg' -print0 | xargs -0 exiftool -warning; find . -iname '*jpg' -print0 | xargs -0 jpeginfo -c
2013-01-28 16:44:19
User: unixmonkey46191
Functions: find xargs
Tags: Image processing image photo jpeg corrupt
0
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Find corrupted jpeg image files

This checks jpeg data and metadata, should be grepped as needed, maybe a -B1 Warning for the first, and a -E "WARNING|ERROR" for the second part....

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for file in *.jpg; do identify -format '%f %b %Q %w %h' $file; done
2012-11-16 10:06:35
User: phattmatt
Functions: file
Tags: ImageMagick jpeg jpg
0
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List image attributes from a folder of JPEG images

Runs the identify command (from ImageMagick) on each jpg file in the current directory and returns image details according to the format parameter. The example here returns:

Filename FileSize Compression Width Height

More information about the available format options can be found here: http://www.imagemagick.org/script/escape.php

I usually redirect the output to a text file using "> listofdetails.txt" at the end. Spreadsheet magic can then be applied.

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find . -type f -name '*.jpg' -exec convert -quality 75 {} {} \;
2011-09-23 13:51:18
User: bobby_tables
Functions: find
Tags: ImageMagick find jpeg jpg
0
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Converts all jpg files to 75 quality.

Requires ImageMagick to be installed.

This command was stolen from @climagic on Twitter.

Probably a duplicate of command below, but this command uses slightly higher quality.

http://www.commandlinefu.com/commands/view/707/compress-images-using-convert-imagemagick-in-a-bulk

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jpegtran -optimize -outfile temp.jpg <JPEG> && mv temp.jpg "$_"
2011-07-24 08:55:46
User: h3xx
Functions: mv
Tags: jpeg
0
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Losslessly optimize JPEG files for file size

You can also save EXIF information by copying it to temp.jpg:

jpegtran -optimize -outfile temp.jpg <JPEG> && jhead -te temp.jpg "$_" && mv temp.jpg "$_"
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pdfimages -j foo.pdf bar
2011-07-07 17:18:36
User: lucasrangit
Tags: pdf jpeg
3
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Extract JPEG images from a PDF document

This will extract all DCT format images from foo.pdf and save them in JPEG format (option -j) to bar-000.jpg, bar-001.jpg, bar-002.jpg, etc.

Inspired by http://stefaanlippens.net/extract-images-from-pdf-documents

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find . -name "*jpg" -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR"
2009-06-03 22:08:48
User: vincentp
Functions: find grep
Tags: Image processing image photo jpeg corrupt
9
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Find corrupted jpeg image files

Finds all corrupted jpeg files in current directory and its subdirectories. Displays the error or warning found.

The jpeginfo is part of the jpeginfo package in debian.

Should you wish to only get corrupted filenames, use cut to extract them :

find ./ -name *jpg -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR" | cut -d " " -f 1
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for i in *jpg; do jpeginfo -c $i | grep -E "WARNING|ERROR" | cut -d " " -f 1 | xargs -I '{}' find /mnt/sourcerep -name {} -type f -print0 | xargs -0 -I '{}' cp -f {} ./ ; done
2009-05-07 00:30:36
User: vincentp
Functions: cp cut find grep xargs
Tags: Image processing image copy jpeg jpg corrupt sync
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sync a directory of corrupted jpeg with a source directory

Find all corrupted jpeg in the current directory, find a file with the same name in a source directory hierarchy and copy it over the corrupted jpeg file.

Convenient to run on a large bunch of jpeg files copied from an unsure medium.

Needs the jpeginfo tool, found in the jpeginfo package (on debian at least).

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