I am creating a bash script that renames photos so that they include date and time in their file name. I would like to build a filename with ImageMagick's identify utility.
identify -format "IMG_%[EXIF:DateTime].jpg" myphoto.jpg
I would like to apply formatting to date and time. How can I do it with ImageMagick? Does identify support formatting?
Use the date utility to reformat the date value. Run man date, and checkout other questions/answers for examples.
img_date=$(identify -format "%t_%[EXIF:DateTime]" input.jpeg)
#=> 2018:07:25 06:28:41
my_date=$(date -j -u -f "%Y:%m:%d %H:%M:%S" "$img_date" +"%Y-%m-%d")
#=> 2018-07-25
convert input.jpeg "output_${my_date}.jpeg"
#=> output_2018-07-25.jpeg
You can do most of it in Imagemagick. But Imagemagick does not have built-in date-time formatting. So you have to capture the date and time and pipe it to your OS to reformat. Then capture the image name without the suffix. Then convert your input to a new image with the desired output name.
Here is an example using Unix tr to reformat the captured data and time where I change spaces to underscores and colons to hyphens.
datetime=$(identify -format "%[EXIF:DateTime]" P1050001.JPG | tr " " "_" | tr ":" "-")
inname=$(identify -format "%t" P1050001.JPG)
convert P1050001.JPG ${inname}_${datetime}.jpg
This creates a new file with the name of P1050001_2009-12-05_16-59-51.jpg
Alternately, you can combine the first two steps as:
newname=$(identify -format "%t_%[EXIF:DateTime]" P1050001.JPG | tr " " "_" | tr ":" "-")
convert P1050001.JPG ${newname}.jpg
If you do not want to use convert to create a new image, then you can use your OS to rename the original.
All of this may be easier done with exiftool as Mark Setchell has suggested.
Related
I have two folders, A and B, with image files that have corresponding names.
For example, each contain files labelled 01.png, 02.png, 03.png, etc.
How can I merge the corresponding files such that I have a third folder C that contains all merged photos so that both of the originals are side by side.
I am on Linux, if that changes anything.
I am not near a computer to thoroughly test, but this seems easiest to me:
#!/bin/bash
# Goto directory A
cd A
# For each file "f" in A
for f in *.png; do
# Append corresponding file from B and write to AB
convert "$f" ../B/"$f" +append ../AB/"$f"
done
Or use GNU Parallel and do them all at once!
cd A
parallel convert {} ../B/{} +append AB/{} ::: *.png
Using ImageMagick version 6, if your images are all the same dimensions, and if your system memory can handle reading all the input images into a single command, you can do that with a command like this...
convert FolderA/*.jpg -set filename:f "%[f]" \
-set option:distort:viewport %[fx:w*2] -distort SRT 0 null: \
FolderB/*.jpg -gravity east -layers composite FolderC/"%[filename:f]"
That starts by reading in all the images from FolderA and extending their viewport to double their width to the right.
Then it adds the special built-in "null:" to separate the lists of images before reading in the second list. Then it reads in all the images from FolderB.
Then after setting the gravity to "east", it composites each image from FolderB over the extended right half of each corresponding image from FolderA. That creates the effect of appending the images side by side.
The command sets a variable at the beginning to hold the filenames of the first list of input files, then uses those as the names of the output files and writes them to FolderC.
If you're using ImageMagick version 7, use the command "magick" instead of "convert".
You can do that with some bash scripting code. Assume you have two folders A and B with the corresponding image names in them. Also you have an empty folder AB to hold the results. Then using ImageMagick with the bash looping code, you can do something like this:
Collect the names of all the files in folder A and put into an array
Collect the names of all the files in folder B and put into an array
Loop over the number of images in the folders
Process them with ImageMagick +append and save to folder AB
outdir="/Users/fred/desktop/AB"
aArr=(`find /Users/fred/desktop/A -type f -iname "*.jpg" -o -iname "*.png"`)
numA="${#aArr[*]}"
bArr=(`find /Users/fred/desktop/B -type f -iname "*.jpg" -o -iname "*.png"`)
numB="${#bArr[*]}"
if [ $numA -eq $numB ]; then
for ((i=0; i<numA; i++)); do
nameA=`basename "${aArr[$i]}"`
nameA=`convert "$nameA" -format "%t" info:`
nameB=`basename "${bArr[$i]}"`
nameB=`convert "$nameB" -format "%t" info:`
convert "${aArr[$i]}" "${aArr[$i]}" +append ${outdir}/${nameA}_${nameB}.jpg
done
fi
When converting an image, ImageMagick's default behavior seems to be to overwrite any existing file. Is it possible to prevent this? I'm looking for something similar to Wget's --no-clobber download option. I've gone through ImageMagick's list of command-line options, and the closest option I could find was -update, but this can only detect if an input file is changed.
Here's an example of what I'd like to accomplish: On the first run, convert input.jpg output.png produces an output.png that does not already exist, and then on the second run, convert input.jpg output.png detects that output.png already exists and does not overwrite it.
Just test if it exists first, assuming bash:
[ ! -f output.png ] && convert input.png output.png
Or slightly less intuitively, but shorter:
[ -f output.png ] || convert input.png output.png
Does something like this solve your problem?
It will write to output.png but if the file already exists a new file will be created with a random 5 character suffix (eg. output-CKYnY.png then output-hSYZC.png, etc.).
convert input.jpg -resize 50% $(if test -f output.png; then echo "output-$(head -c5 /dev/urandom | base64 | tr -dc 'A-Za-z0-9' | head -c5).png"; else echo "output.png"; fi)
I'm considering using ImageMagick to extract images from individual pages from a PDF file. How can I capture the names of the files getting generated by it? It seems that the -verbose option includes information on the files getting generated, but is that a reliable way of gathering that? Any other alternatives?
Depending on what you want to do, I think you have at least 3 options...
Option 1
If you want to know the number of pages up front, a priori, you can get ImageMagick to tell you like this:
identify -format %n FreddyFrog.pdf
8
or if you want it in a variable,
pages=$(identify -format %n FreddyFrog.pdf)
echo $pages
8
Option 2
You can tell ImageMagick how to format the names of the output files, like this, where the %04d says to use 4 digits and front-pad with zeroes:
convert -density 72 FreddyFrog.pdf FreddyFrog-%04d.tif
Then you will automatically know the names of the output files.
ls FreddyFrog-*
FreddyFrog-0000.tif FreddyFrog-0003.tif FreddyFrog-0006.tif
FreddyFrog-0001.tif FreddyFrog-0004.tif FreddyFrog-0007.tif
FreddyFrog-0002.tif FreddyFrog-0005.tif
Option 3
You can use the shell to draw a line in the sand before you convert the files and then find everything newer afterwards:
> before # or "touch before" if you prefer
convert FreddyFrog..... # strut your IM stuff
for f in *; do [[ "$f" -nt before ]] && echo $f; done # list files newer than line in sand
rm before # clean up
rm before
how to use grep to find occurrences of words from a dictionary file which have a given set of letters with the restriction that each letter occurs once and only once.
EG if the letters are abc then the expected output is:
cab
EDIT:
Given a dictionary file (that is a file containing one word per line such as /usr/share/dict/words on mac os x operating system) and a set of (unique) characters, I want to print out all of the dictionary file's words that contain each character of the input set once and only once. For example if the set of characters is {a,b,c} then print out all (3-letter) words that contain each character of the set.
I am looking, preferably, for a solution that uses just grep expressions.
Given a series of letters, for example abc, you can convert each one to a lookahead, like this:
^(?=[^a]*a[^a]*)(?=[^b]*b[^b]*)(?=[^c]*c[^c]*)$
You may need to use the "extended regex" flag -E to use this regex with grep.
To create this regex from a string, you could use sed (an exercise for the reader)
grep -E ^[abc]{3}.$ <Dictionary file> | grep -v -e a.*a -e b.*b -e c.*c
i.e. Find all three letter strings matching the input and pipe these through inverse grep to remove strings with double letters.
I'm using the '.' after {3} because my dictionary file is windows based so has an extra carriage return or line feed. So, that's probably not necessary.
Below is a Perl solution. Note, you'll need to add more words to the dictionary, and read input in to the $input variable. An array of valid words will end up in #results.
#!/usr/bin/env perl
use Data::Dumper;
my $input = "abc";
my #dictionary = qw(aaa aac aad aal aam aap aar aas aat aaw aba abc abd abf abg
abh abm abn abo abr abs abv abw aca acc ace aci ack acl acp acs act acv ada adb
adc add adf adh adl adn ado adp adq adr ads adt adw aea aeb aec aed aef aes aev
afb afc afe aff afg afi afk afl afn afp aft afu afv agb agc agl agm agn ago agp
...
PUT A REAL DICTIONARY HERE!
...
zie zif zig zii zij zik zil zim zin zio zip zir zis zit ziu ziv zlm zlo zlx zma
zme zmi zmu zna zoa zob zoe zog zoi zol zom zon zoo zor zos zot zou zov zoy zrn
zsr zub zud zug zui zuk zul zum zun zuo zur zus zut zuz zva zwo zye zzz);
# Generate a lookahead expression for each character in the input word
my $regexp = join("", map { "(?=.*$_)" } split(//, $input));
my #results;
foreach my $word (#dictionary) {
# If the size of the input doesn't match the dictionary word, skip to the
# next word.
if (length($input) != length($word)) {
next;
}
if ($word =~ /$regexp/) {
push(#results, $word);
}
}
print Dumper #results;
The solution I found involves using grep first to extract all n-letter words that contain only letters from the input set - although some letters might appear more than once, some may not appear; (again I am assuming that the input letters are unique). Then it does a series of 1-letter greps to make sure each letter occurs at least once. Because the words are of length n this ensures the word contains each letter once and only once. For example, if the input character set is (a,b,c} then the solution would be:
grep -E '^[abc]{3}$' /usr/share/dict/words | grep a | grep b | grep c
a simple bash script can be written which creates this grep string and executes it against the word file, using $1 as the input letter set. It might not be the most efficient method of generating the string, but as I am not familiar with sed or awk it does seem to solve my problem. The script I created is:
#!/bin/sh
slen=${#1}
g2="'^[$1]{$slen}\$'"
g3=""
ix1=0
while [ $ix1 -lt $slen ]
do
g3="$g3 | grep ${1:$ix1:1}"
ix1=$((ix1+1))
done
eval grep -E $g2 /usr/share/dict/words $g3
I would like to convert a pdf file to a Black and White PDF file with ImageMagick. But I've got two problems:
I use this command:
convert -colorspace Gray D:\in.pdf D:\out.pdf
But this command convert only the FIRST page... How to convert all pages?
After use this command the resolution is terrible... but if I use -density 300 option the file size has increased more than double. So I would like to use the same DPI setting, but how to use?
Thanks a lot
Assuming you have all the necessary command line tools installed you can do the following:
Split and join PDF using pdfseparate and pdfunite (Poppler tools).
Extract the original density using pdfinfo plus grep/egrep and, for instance, sed. This will not guarantee the same size of the PDF file, just the same DPI.
Putting it all together you can have a series of bash commands as following:
pdfseparate in.pdf temp-%d.pdf; for i in $(seq $(ls -1 temp-*.pdf | wc -l)); do mv temp-$i.pdf temp-$(printf %03d $i).pdf; done
for f in temp-*.pdf; do convert -density $(pdfinfo $f | egrep -o 'Page size:[[:space:]]*[0-9]+(\.[0-9]+)?[[:space:]]*x[[:space:]]*[0-9]+(\.[0-9]+)?' | sed -e 's/^Page size:\s*//'| sed -e 's/\s*x\s*/x/') -colorspace Gray {,bw-}$f; done
pdfunite bw-temp-*.pdf out.pdf
rm {bw-,}temp-*.pdf
Note 1: there as a dirty workaround (for/wc/seq/printf) for a proper ordering of 10-999 pages PDFs (I did not figure out how to put leading zeros in pdfseparate).
Note 2: I guess ImageMagick treats PDFs as just another binary image file so for instance for mainly text files this will result in huge PDFs. Thus, this is a very bad method to convert text-based PDFs to B&W.