Whenever I try to execute the following shell command , it works properly .
convert maanavulu_GIST-TLOTKrishna.tif -alpha set -matte -virtual-pixel transparent -set option:distort:viewport 1000x1000 -distort perspective-projection '1.06,0.5,0,0,1.2,0,0,0' -trim 1.jpg
But , whenever I try assign the command to a variable and then execute it , it reports the following error .
convert.im6: invalid argument for option PerspectiveProjection : 'Needs 8 coefficient values' # error/distort.c/GenerateCoefficients/873.
The short of it: it's best to:
store your arguments in an array
not including the command itself, for safety (preferable to an eval solution)
then invoke the command with the array
# Store options in array - note that the filenames are excluded here, too,
# for modularity
opts=(-alpha set -matte -virtual-pixel transparent -set option:distort:viewport \
1000x1000 -distort perspective-projection '1.06,0.5,0,0,1.2,0,0,0' -trim)
# Invoke command with filenames and saved options
convert maanavulu_GIST-TLOTKrishna.tif "${opts[#]}" 1.jpg
Afterthought: As #konsolebox and #chepner point out: using a function is probably the best choice (clear separation between fixed and variable parts, encapsulation, full range of shell commands available).
The proper way to assign-and-execute a command is to use an array:
COMMAND=(convert maanavulu_GIST-TLOTKrishna.tif -alpha set -matte -virtual-pixel transparent -set option:distort:viewport 1000x1000 -distort perspective-projection '1.06,0.5,0,0,1.2,0,0,0' -trim 1.jpg)
Then execute it:
"${COMMAND[#]}"
I like eval but it's definitely not the solution this time.
And just a tip: If you can use a function, use a function. And quote your arguments properly.
Quotes are not processed after expanding a variable. The only processing that occurs is word splitting and wildcard expansion. If you need to perform all the normal steps of command execution, you have to use eval:
eval "$variable"
Related
To create an image thumbnail using an older version of ImageMagick, it was possible in the following ways:
(To aid in futher referencing, examples are numbered.)
1. convert.exe image.jpg -thumbnail 100x100 ./converted/converted_image.jpg
2. mogrify.exe -thumbnail 100x100 -path ./converted image.png
Now I have ImageMagick 7 (downloaded just yesterday), and during installation I intentionally turned "Install legacy utilities (e.g. convert.exe)" checkbox off. That is, I have only one utility in my ImageMagick directory: magick.exe.
I'm trying to understand what is the correct and future-proof way to perform above-mentioned operations according to modern ImageMagick versions.
A quote from https://imagemagick.org/script/porting.php#cli:
animate, compare, composite, conjure, convert, display, identify, import, mogrify, montage, stream
To reduce the footprint of the command-line utilities, these utilities are symbolic links to the magick utility. You can also invoke them from the magick utility, for example, use magick convert logo: logo.png to invoke the magick utility.
In the same source:
With the IMv7 parser, activated by the magick utility, settings are applied to each image in memory in turn (if any). While an option: only need to be applied once globally. Using the other utilities directly, or as an argument to the magick CLI (e.g. magick convert) utilizes the legacy parser.
Hmm...
Works:
3. magick.exe convert image.jpg -thumbnail 100x100 ./converted/converted_image.jpg
4. magick.exe mogrify -thumbnail 100x100 -path ./converted image.png
Still works (the same way as magick.exe convert):
5. magick.exe image.jpg -thumbnail 100x100 ./converted/converted_image.jpg
However, the following one doesn't work (expected: should work the same way as magick.exe mogrify):
6. magick.exe -thumbnail 100x100 -path ./converted image.png
My question is: Which syntax should I use for convert and for mogrify? 3 and 4, or 4 and 5, or something different?
AFAIK, and I am happy to add any corrections suggested, it works like this.
The first idea is that you should use version 7 if possible and all the old v6 commands, WITH THE EXCEPTION OF convert should be prefixed with magick. That means you should use these
magick ... # in place of `convert`
magick identify ... # in place of `identify`
magick mogrify ... # in place of `mogrify`
magick compare ... # in place of `compare`
magick compose ... # in place of `compose`
If you use magick convert you will get old v6 behaviour, so you want to avoid that!
Furthermore, v7 is more picky about the ordering. You must specify the image you want something done to before doing it. That means old v6 commands like:
convert -trim -resize 80% input.jpg output.jpg
must now become:
magick input.jpg -trim -resize 80% output.jpg # magick INPUT operations OUTPUT
So, looking specifically at your numbered examples:
Should become:
magick image.jpg -thumbnail 100x100 ./converted/converted_image.jpg
Should become:
magick mogrify -thumbnail 100x100 -path ./converted image.png
invokes old v6 behaviour because you use magick convert instead of plain magick, and should be avoided
Is correct, modern syntax
Is correct, modern syntax
Looks like you meant magick mogrify because you didn't give input and output filenames and because you use -path, but it looks like you accidentally omitted mogrify. If you didn't accidentally omit mogrify, then you probably meant to use the old convert-style command, and need an input and an output file and you need to specify the input file before the -thumbnail.
Keywords: Usage, wrong, modern, v7 syntax, prime.
I have the following snippet in my bash script
#!/bin/bash
for ((i=100; i>=70; i--))
do
convert test.png -quality "$i" -sampling-factor 1x1 test_libjpeg_q"$i".jpg
done
How can i execute the for loop in parallel using all cpu cores.I have seen gnu parallel being used but here i need the output filename in a specific naming scheme as shown above
You can use parallel like this:
parallel \
'convert test.png -quality {} -sampling-factor 1x1 test_libjpeg_q{}.jpg' ::: {100..70}
I am attempting to execute a bash script from the command line.
Sometimes it will require an argument that contains spaces.
bash test.sh -l "path/to/image/may contain spaces.png"
What is the correct way to provide this? I have tried escaping \ but to no avail.
I receive the following error;
bash splash.sh -b \#\000000 -l \"img/Rev Logo.jpg\"
convert: unable to open image ''"img/Rev'': No such file or directory # error/blob.c/OpenBlob/3093.
Which relates to this bit of code;
logo="$1"
if checkBackground -eq 1
then
convert -size $size canvas:$back -background $back $tmp01
fi
convert \'$logo\' -background $back $tmp02
composite $tmp02 -gravity center $tmp01 output.jpg
If the first argument to the script is "foo bar", then this line:
convert \'$logo\' -background $back $tmp02
is passing as its first argument to convert the string 'foo and passing the second argument bar'. You probably don't want that. Change that line to:
convert "$logo" -background "$back" "$tmp02"
In general, double quote any variables.
And when you invoke the script, just quote the argument. If you call the script as:
bash splash.sh -b \#\000000 -l \"img/Rev Logo.jpg\"
then you are passing two separate arguments: "img/Rev and Logo.jpg". It is perfectly valid to have a filename with a double quote in it, but very unusual. If you want to pass the single argument img/Rev Logo.jpg, you want to invoke your script as:
bash splash.sh -b "#000000" -l "img/Rev Logo.jpg"
or
bash splash.sh -b \#000000 -l img/Rev\ Logo.jpg
I'm trying to write a bash script to trim the scanner white space around some old photos that were scanned in ages ago. I've got hundreds of photos so I'm not doing it manually.
Fred's imagemagick scripts don't manage to select the appropriate area.
I am no programmer so please dont be too offended by my terrible attempts at scripting!
I've found a combination of commands using imagemagick that does it.
first I use a blurring filter to confuse imagemagick into correctly selecting the photo size:
convert input -virtual-pixel edge -blur 0x15 -fuzz 15% -trim info:
This spits out data as follows:
0001.jpeg JPEG 3439x2437 4960x6874+1521+115 8-bit DirectClass 0.070u 0:00.009
I then use the numbers to do a crop which has been very accurate on my scans. The following is an example using the numbers from above.
convert inputfile -crop 3439x2437+1521+115 +repage outputfile
My problem is in writing the bash file to go through a directory of pictures and automate the process.
Here's what I have so far:
#!/bin/bash
ls *.jpeg > list
cat list | while read line; do
convert $line -virtual-pixel edge -blur 0x15 -fuzz 15% -trim info: > blurtrim.txt
#need a line to manipulate the output of the above to spit out the crop coordinates for the next command
crop=$(<crop.txt)
convert $line -crop $crop +repage trim$line.jpeg
rm blurtext.txt
rm crop.txt
done
rm list
The key bit I can't do is changing the string output of the first imagemagick command.
the file goes along the lines of:
input fileformat 1111x2222 3333x4444+5555+666 and then a load of crap i dont care about
the numbers I need in my script are:
1111x2222+5555+666
the cherry on the top is that while most of the numbers are four digits long not all of them are so I cant rely on that.
any ideas on how to use sed or preferably something else less demonic to get the above numbers in my script?
an explanation of the syntax would be nice (but i understand if the explantion is the size of a book then its best left out).
thanks in advance!
You don't need to parse anything! ImageMagick can tell you the trim box directly itself, using the %# format:
convert image.jpg -virtual-pixel edge -blur 0x15 -fuzz 15% -format "%#" info:
1111x2222+5555+666
So, you can say:
trimbox=$(convert image.jpg -virtual-pixel edge -blur 0x15 -fuzz 15% -format "%#" info:)
convert image.jpg -crop $trimbox ...
Benefits include the fact that this approach works on Windows too, where there is no sed.
So, the full solution would be something like:
#!/bin/bash
shopt -s nullglob
for f in *.jpeg; do
trimbox=$(convert "$f" -virtual-pixel edge -blur 0x15 -fuzz 15% -format "%#" info:)
convert "$f" -crop "$trimbox" +repage "trimmed-$f"
done
Solution
This will parse your file line by line, extract the desired parameters, concatenate them together, and use it as the argument value to 'crop' for the convert program:
regex='([0-9]+x[0-9]+) [0-9]+x[0-9]+\+([0-9]+\+[0-9]+)'
while read line
do
if [[ $line =~ $regex ]]
then
cropParam="${BASH_REMATCH[1]}+${BASH_REMATCH[2]}"
convert inputfile -crop $cropParam +repage outputfile
else
echo "ERROR: Line was not in the expected format ($line)"
exit 1;
fi
done < blurtrim.txt
Explanation
The regex variable holds a regular expression (brief introduction to regular expressions in bash here: http://www.tldp.org/LDP/abs/html/x17129.html) which describes the format of the numbers you describe in your question. The () around parts of the pattern denotes something called a capture group. If the pattern matches, the part that is in the first () is captured in a bash variable BASH_REMATCH[1], and the second () is captured in BASH_REMATCH[2]. BASH_REMATCH[0] contains the whole match, in case you're wondering why we start at index 1.
The line [[ $line =~ $regex ]] is what actually executes the pattern matching algorithm for us. In Bash [[ is called the extended test command, and the operator =~ is called the regular expression matching operator. This article explains the operator in more detail: http://www.linuxjournal.com/content/bash-regular-expressions.
I would propose a similar solution to Jonathan:
re='([0-9x]+) [0-9x]+(\+[0-9+]+)'
for file in *.jpeg; do
output=$(convert "$file" -virtual-pixel edge -blur 0x15 -fuzz 15% -trim info:)
if [[ $output =~ $re ]]; then
crop="${BASH_REMATCH[1]}${BASH_REMATCH[2]}"
convert "$file" -crop "$crop" +repage "trim$file.jpeg"
fi
done
The regular expression captures any group containing characters within the range 0-9 or x and then a + followed by numbers and + characters. It is a less strict pattern as it includes the x and + inside the bracket expressions, so technically would allow things like 0x9x9x0 but I can't imagine that this would present a problem based on the output you've shown us.
The other differences between this and your original attempt are that no temporary files are created and the loop is run over the list of files, rather than using ls, the parsing of which should generally be avoided in scripts.
I have a folder of images over 4MB - let's call this folder dsc_big/. I'd like to use convert -define jpeg:extent=2MB to convert them to under 2MB and copy dsc_big/* to a folder dsc_small/ that already exists.
I tried convert dsc_big/* -define jpeg:extent=2MB dsc_small/ but that produces images called -0, -1, and so on.
What do I do?
convert is designed to handle a single input file as far as I can tell, although I have to admit I don't understand the output you're getting. mogrify is better suited for batch processing in the following style:
mogrify -path ../dsc_small -define jpeg:extent=2MB dsc_big/*
But honestly I consider it dangerous for general usage (it'll overwrite the original images if you forget that -path) so I always use convert coupled with a for loop for this:
for file in dsc_big/*; do convert $file -define jpeg:extent=2MB dsc_small/`basename $file`; done
The basename call isn't necessary if you're processing files in the current directory.
This was the command which helped me after a long try.
I wanted to make same sized thumbnails from a big list of large images which have variable width and height . It was for creating a gallery page.
convert -define jpeg:size=250x200 *.jpg -thumbnail 250x200^ -gravity center -extent 250x200 crop/thumbnail-%d.jpeg
I got re-sized thumbnails which all having same width and height. :) thanks to ImageMagick.
Here's a solution without using for loops on the console
convert *.jpeg -define jpeg:extent=2MB -set filename:f '../dsc_small/%t_small.%e' +adjoin '%[filename:f]'
Although this is an old question, but I'm adding this response for the benefit of anyone else that stumbles upon this.
I had the same exact issue, and being discouraged by the use of mogrify, I wrote a small Python based utility called easymagick to make this process easier while internally using the convert command.
Please note, this is still a work in progress. I'll appreciate any kind of feedback I can get.
I found that cd-ing into the desired folder, and then using the bash global variable $PWD made my convert not throw any errors. I'm utilizing ImageMagick's recently implemented caption: http://www.imagemagick.org/Usage/text/#caption function to label my images with the base filename and place them in another directory within the first.
cd ~/person/photos
mkdir labeled
for f in $PWD/*.JPG; do
width=$(identify -format %w $f)
filename=$(basename $f .JPG)
convert -background '#0008' -colorspace transparent -fill white -gravity center -size ${width}x100 caption:"${filename}" ${f} +swap -gravity south -composite "$PWD/labeled/${filename}.jpg";
done
This works for me
convert -rotate 90 *.png rotate/image.jpg
produces image-0.jpg, image-1.jpg, image-2.jpg ..... in the 'rotate' folder. Don't know of a way to preserve the original filenames though.