Imagemagick input image to thumbnail squared image - image

As stated in the title i have to create a squared image starting from any kind of input image.
If the input image is smaller than thumbnail then i have only to pad it, otherwhise (if geater) should be shrinked without change aspect ratio) so for example :
After few test come up with the following code :
mogrify -auto-orient -define jpeg:fancy-upsampling=off:size={with}x{height}^> -thumbnail {with}x{height}^> -gravity center -extent {with}x{height}^> -background white -quality {dpi} -format {format} -path {path} *.*
Everything work as intended, except for few corner cases.
If the input image is really smaller compared to thumnail size, then the input image tend to disappear (because really small compared to thumbnail size).
So i am trying to figure it how to avoid excessive padding (only the strictly necessary to make the picture squared) when source image is smaller than thumbnail size (and so due to '>' command imamagick will not shrink it).

Related

Batch Resize Photos While Maintaining the Aspect Ratio AND Fitting to a specific pixel size

I am looking to batch resize pictures to a specific pixel size while maintaining the aspect ratio. Is their a way that the picture aspect can be preserved and the rest of the space can be filled in with white? For example, I resize an image to 200 x 200 and due to preserving the aspect ratio it is changed to 200 x 194. I would like the actual image to remain 200 x 194 and white space to fill in the remaining area to create an image that is 200 x 200 px. Thank you in advance!
You can do that with ImageMagick which is included in most Linux distros and is available for macOS and Windows.
Just in Terminal, or Command Prompt on Windows:
magick input.jpg -background white -resize 200x200 -gravity center -extent 200x200 result.jpg
If you have many files to do, you may be better using ImageMagick's mogrify command, which will do them all in one go for you! So make a new directory called processed for the output files and then use this to process all PNG files in the current directory:
magick mogrify -path processed -background white -resize 200x200 -gravity center -extent 200x200 '*.png'
I don't know if you are on Windows or not, so you may or may not need the single quotes around the filenames at the end of that command. Basically, it determines whether the expansion of the filename list is done by the shell (which has limitations on the number of files), or internally by ImageMagick (which does not).
If you are running anything older than v7, the commands become:
convert input.jpg ...
or
mogrify ...

How to give an image an old, dusty appearance with faded colours?

I have images of old paintings. The paintings are old and dusty with faded colours as shown here.
How do I give any image this type of an 'old' appearance? I couldn't find any filters or openCV functions to achieve this type of look?
EDIT: My question is different as the other one solves the problem using the sepia filter and using the grain effect. I'm not looking for that sort of an appearance. I want my image to look like an old damaged painting. This means that the colours should be faded and it should have an overall dusty appearance.
There's no real need to write any code and use OpenCV, since you can do all that on the command-line with ImageMagick which is installed on most Linux distros and is available for macOS and Windows.
First, fading. This can be simulated by reducing the saturation of an image. So if we start with this Mona Lisa image:
We can fade her using this command to leave the brightness unchanged at 100% of its original value and reduce the saturation to 50% of its original value. I am intentionally "over-egging" everything so you can see it clearly. You should maybe be more subtle.
convert mona.jpg -modulate 100,50 result.jpg
Next, vignetting - or dark corners. You can use something like this:
convert mona.jpg \
\( +clone -fill white -colorize 100 -background "gray(50%)" -vignette 0x15+1+1% \) \
-compose multiply -composite result.jpg
The 0x15 controls the roll-off, or how gradual the change is, so increase the 0x15 if you want a smoother roll-off or go down to 0x5 if you want it harder. The +1+1% means that the ellipse will be 1% smaller than the width of the image and 1% smaller than the height of the image. So if you want a smaller light hole and bigger dark corners, go for +10+10%. The degree of darkening is controlled by the gray(50%) so you can diddle with that till you are happy too :-)
Finally, dust. Best thing is to get a PNG image of some dust, resize it to match the size of your image and overlay it.
First get the size of Mona:
identify mona.jpg
mona.jpg JPEG 403x600 403x600+0+0 8-bit sRGB 57130B 0.000u 0:00.000
So, she is 403x600. Here is a sample of some dust - again, you can be more subtle - I am just being heavy-handed so it shows:
Let's resize the dust to match and overlay it:
convert mona.jpg \( dust.png -resize 403x600\! \) -composite result.jpg
Then you can combine all three effects, fading, vignetting and dust, into a single command:
convert mona.jpg -modulate 100,50% \
\( +clone -fill white -colorize 100 -background "gray(50%)" -vignette 0x15+1+1% \) \
-compose multiply -composite \
\( dust.png -resize 403x600\! \) -composite result.jpg
If you have lots of images to process, you can script the whole lot to be done in parallel very easily with GNU Parallel - see some of my other answers for examples.
Keywords: artificial ageing, image ageing, command-line, command line, ImageMagick, magick, old, old photo, photo effect, convert, dust, scratches, fading, faded.
I would suggest using a style transfer tool, rather than manually coming up with a procedure to mimic the style of an old painting. There are plenty free style transfer tools and libraries available.
I would suggest using OpenCV various filters to create the effect you need. You have to try various filters and try to figure what works for you, But I have suggestions which you can try.
For color, fading try Erode and Dilate with small kernel size.
Next, add some noise, Salt and Pepper will do just fine, also try gaussian filter after applying noise. Salt and Pepper is non-linear noise and Gaussian is a linear filter so it will just spread the noise, but keep the filter kernel small.
Try finding some images of dust, torn page edges (WITHOUT BACKGROUND) like in the following link:
https://www.google.co.in/searchq=dust+png+images&newwindow=1&rlz=1C1CHBF_enIN797IN798&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjtq7ZvfPcAhXJO48KHQ2UD0kQ_AUICigB&biw=1536&bih=759#imgrc=_
Keeping alpha transparency in mind, mask these over your images.
With all the things in correct proportion and sequence, You will get your old dusty image.

converting a ps image to gif image with length x900 y800

I have a ps image that I want to convert to a gif image with horizontal by vertical dimensions of 900 and 800 respectively. I have tried to use the command:
convert panel.gs -resize x800 y900 panel.gif
or also:
convert panel.gs -resize 900x800 panel.gif
Can you help me to tweak the convert commands so I can get the desired results?
.gs is not a valid suffix. Did you mean .ps?
Imagemagick will need ghostscript as a delegate. You did not say what was wrong nor what platform or what version of Imagemagick.
If the image does not have the same aspect ratio as the final dimensions you want, you will either 1) need to distort it to fit using !, 2) resize it and then extend to the size you want filling with background color, or 3) resize it with ^ and crop it to the size you want.
convert panel.ps -resize "900x800!" panel.gif
convert panel.ps -resize 900x800 -gravity center -background white -extent 900x800 panel.gif
convert panel.ps -resize "900x800^" -gravity center -extent 900x800 panel.gif
Well, firstly you haven't actually said what's wrong with the two commands that you have tried already.....
Your PostScript program probably does not contain an 'image' as such, PostScript is not a bitmap format its a programming language.
You can use Ghostscript to render the PostScript to an image, and then use ImageMagick to resize that image, possibly you can combine these two steps, or just perform a single conversion, it depends on what exactly you want to happen, which isn't clear.
If (for example) your PostScript program requests a media size of 9 inches by 8 then you can create a bitmap image by simply setting the resolution to 100 dpi using -r100.
If you want the image scaled differently in each direction, then you need to set a non-square resolution. For example if the PostScript program requests media of 9 inches by 4 then you need to set the resolution to 100x200 in order to get an image exactly 900 x 800 pixels. You would use -r100x200 for this.
The alternative, from a PostScript point of view, is to set the media size to a given
value in pixels (using -g900x800) and set -dDFIXEDMEDIA which prevents the PostScript program from changing it. You can then use -dFitPage which will have Ghostscript scale the content to fit the page. However it will scale the content equally in both directions, which may leave white space around the edge.
Now since Ghostscritp doesn't write GIF directly you'll need to load whatever bitmap format you select into IM in order to write it out as a GIF, so perhaps the simplest solution is just to use Ghostscript to render the PostScript to a defined resolution (eg 100 dpi) and then load that image into IM and rescale it there.
Since IM (and therefore convert) use Ghostscript to process PostScript programs, that's what's happening now so it isn't obvious to me what your problem is.

Change Pixel Values of Image to remove Date

What is the most efficient technique to remove the date that a Camera embeds on any image it takes.
The task is to prepare a script/code/software that shall remove the date from the given input image file (jpeg, png).
Please let me know an optimum way to accomplish this.
Thank you.
Here is an alternative approach to the question. You can determine the average colour of the bottom right corner of the image (size 250px wide x 100px high) with Imageagick like this:
ave=$(convert sign.jpg -gravity southeast -crop 250x100+0+0 -scale 1x1 -format "%[pixel:p{0,0}]" info:)
That will give you the value srgb(199,181,119) for this image. Now you can create a rectangle (200px x 50px) that colour and overlay it onto the image and then blur the edges a little to blend it in:
convert sign.jpg \( -size 200x50 xc:"$ave" \) -geometry +970+780 -composite -region 240x90+950+760 -blur 0x10 out.jpg
I am not sure if you were hoping for something that is forensically indetectable or something that more or less removes the distraction somewhat. Hopefully the latter :-)
A little measuring around shows that the date is located at the following position:
150x40+650+520
i.e. 150 pixels wide by 40 pixels high, located 650 pixels to the right of the top left corner and 520 pixels down from the top left corner.
So, one approach would be to copy the piece of the image directly below that, and paste it on top of the date, which can be done in ImageMagick in one command like this:
convert sign.jpg \( +clone -crop 150x40+650+560 +repage \) -geometry +650+520 -composite out.jpg
That says... take the original image and create a copy of it (+clone), then cut out the piece specified after the crop command command and reset that as though it was the top left corner (+repage). Then paste (-composite) that image at offset +650+520 on top of the original image and save the result as out.jpg.
It is not a beautifully engiineered solution, but may be good enough. It may be desirable to blur the area a little, to help disguise it. Alternatively, it may be possible to select the colours within the date and make them transparent, then to displace the original image a little behind the transparent holes to fill them - I didn't choose that option because it is harder and because you may not like ImageMagick anyway, and there are actually several colours within the date field ranging from browns to golden yellows and selecting them without affecting the remainder of the image might start getting fun!
ImageMagick is free and available for Windows, OSX, Linux etc from here. It is ready installed on most Linux distros anyway.

Using ImageMagick to add whitespace to images in bulk

I have a bunch of images that are rectangular and I need them to be square, i.e. 1000x1000, so I've decided to use ImageMagick to pad the sides of the image with the amount of whitespace necessary to make the image square.
I've found the code from the following link useful (see next paragraph). But this requires me to process each image individually, to set the filename and then the -thumbnail dimensions. How can I use this same process to process an entire folder?
Here's the code and the link to it:
http://imagemagick.org/Usage/thumbnails/#pad
convert -define jpeg:size=200x200 hatching_orig.jpg -thumbnail '100x100>' \
-background white -gravity center -extent 100x100 pad_extent.gif
It is not very clear from your question what you actually have (i.e. how big your images are? what format are they?), nor what you actually want (you only provide an example that doesn't do what you want. But I'll take your question at the face-vale of the title and hope you can work out anything missing from there.
If you want to do ImageMagick in bulk, you either need to use a loop in bash, like this:
#!/bin/bash
for f in *.jpg; do
convert "%f" ...
done
or use IM's mogrify command. That is quite a powerful command, so make a backup of your images before you even think of trying to use it.
Let's assume you want to place all JPEG images in the current directory onto a white 1000x1000 pixel background. You would do this:
mogrify -background white -gravity center -extent 1000x1000 *.jpg
Updated Answer
It should be possible to do the resizing and the white padding in a single ImageMagick command without needing to use SIPS as well, like this if you now want 1200x1200 square images padded with white:
mogrify -background white -gravity center -resize 1200x1200\> -extent 1200x1200 *.jpg

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