noobie question:
i try to batch convert some files via imagemagick with
for i in *.jpg; do convert $i -colorspace Gray -rotate -90 -verbose out/%03d.jpg; done
it do convert the right way, but overwrites the output file on each loop instead of
continuing with the progressiv number intended with %03d.
input1.jpg=>out/000.jpg JPEG 2479x3508=>3508x2479 3508x2479+0+0 8-bit Grayscale DirectClass 483KB 0.420u 0:00.339
input2.jpg=>out/000.jpg JPEG 2479x3508=>3508x2479 3508x2479+0+0 8-bit Grayscale DirectClass 1.36MB 0.470u 0:00.390
input3.jpg=>out/000.jpg JPEG 2479x3508=>3508x2479 3508x2479+0+0 8-bit Grayscale DirectClass 1.733MB 0.490u 0:00.410
input4.jpg=>out/000.jpg JPEG 2479x3508=>3508x2479 3508x2479+0+0 8-bit Grayscale DirectClass 2.806MB 0.560u 0:00.480
you see, its always overwriting 000.jpg
I need some hints to go forth...
dearest
lippe
# Define a variable to increment
counter=0
# Iterate over images
for image in *.jpg; do
# Convert number from `1' to pretty format `001'
printf -v pretty_counter "%03d" $counter
# Convert image
convert $image -colorspace Gray -rotate -90 -verbose out/$pretty_counter.jpg
# Increment counter
counter=$(( $counter + 1 ))
done
Or just
convert *.jpg -colorspace Gray -rotate -90 -verbose out/%03d.jpg
Explanation
ImageMagick's escape sequence references the image stack. As your invoking the convert command inside the for loop, only one image will exist in the stack, and thus only file out/000.jpg will be generated. Solution would be to use bash to generate the output filename, or give convert the all files at once.
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'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 am using ImageMagick to resize image resolution by using below command-line option
convert abc.png -set units PixelsPerInch -density 75 abc_a.png
I am in need of this: if any images has more than 300 width OR more than 100 height, I want to convert it to width 300 width and 100 height, with changing above dpi (i.e. 75dpi).
Can any one help me on this?
If you are on Linux/OSX, you can get the image dimensions like this:
identify -format "%w %h" input.jpg
So, if you want the width and height in variables w and h, do this:
read w h < <(identify -format "%w %h" input.jpg)
Now you can test the width and height and do further processing if necessary:
[ $w -gt 300 -o $h -gt 100 ] && convert input.jpg -set units ...
Or, if you want to be more verbose:
if [ $w -gt 300 -o $h -gt 100 ]; then
convert ...
fi
So, the total solution I am proposing looks like this:
#!/usr/bin/bash
read w h < <(identify -format "%w %h" input.jpg)
[ $w -gt 300 -o $h -gt 100 ] && convert input.jpg -set units ...
JPEG or PNG makes no difference, so just replace my JPG with PNG if that is the format of your choice.
Updated for Windows
Ok, no-one else is helping so I will get out my (very) rusty Windows skills. Get the image width something like this under Windows:
identify -format "%w" input.png > w.txt
set /p w=<w.txt
Now get the height:
identify -format "%h" input.png > h.txt
set /p h=<h.txt
You should now have the width and height of image input.png in 2 variables, w and h, check by typing
echo %w%
echo %h%
Now you need to do some IF statements:
if %w% LEQ 300 GOTO SKIP
if %h% LEQ 100 GOTO SKIP
convert ....
:SKIP
Note:: You may need ^ in front of the percent sign in Windows.
Note: You may need double # signs in scripts because Windows is illogical.
You cannot control the -density and the width plus height at the same time!
Density (or resolution), when creating an image, will automatically resize the image to a certain number of pixels in width and height (or it will have been ignored).
Density (or resolution), when displaying an image (like in a browser window, within a HTML page, or on a PDF page), will not change the original images dimensions: instead it will zoom in or zoom out the respective view on the image.
Density (or resolution), when used in the metadata of an image (which is not supported by every file format), does not change the image dimensions -- it just gives a hint to the displaying software, at what zoom level the image wants to be displayed (which is not supported by every image viewer).
Now to your question...
Try this command:
convert abc.png -scale 300x100\> abc_a.png
This will scale the image only if
either the original image's width is larger than 300 pixels,
or the original image's height is larger than 100 pixels.
The scaling will preserve the aspect ratio of the original image. -- Is this what you are looking for?
If the image is smaller, then no scaling will happen and abc_a.png will have the original dimensions.
If you want to *emphatically scale the image to 300x100, no matter what, and loose the aspect ratio, bearing with some distortion of the original image, the use:
convert abc.png -scale 300x100\! abc_b.png
(However, this will also scale smaller images...)
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/${filename}.jpg";
done
This works for me
convert -rotate 90 *.png rotate/image.jpg
produces image-0.jpg, image-1.jpg, image-2.jpg ..... in the 'rotate' folder. Don't know of a way to preserve the original filenames though.
Is there a way to adjust all image sizes in a directory?
If I set the max size to 800x600 it will make larger ones smaller and leave smaller ones at their original size.
for img in *.png; do
convert "$img" "800x600>" $(basename "$img" .png)_new.png
done
convert is from ImageMagick. ">" says it's only resized if larger. See here for its other options.
image magick package needs to be installed:
mogrify -resize 320x240 *.jpg
where 320 = width, 240 = height
or you can just leave width parameter:
mogrify -resize 320 *.jpg
and rest will be taken care of.
Various packages exist for command line or script driven manipulation of image files.
I'd suggest looking at netpbm, or ImageMagick. Personally I prefer the former as it's far simpler to use.