How do these photos work? Can they be made with photoshop?
>>428261do you have more examples?
This is just a test
>>428290test 2
I found this
>>428261i have no idea how this is donebut i am guessing that the creator of this image knows exactly how 4chan resizes for thumbnails and makes it so the minimum number of pixels are for the other picture. when you blow it up, you get all the pixels and the thumbnail pic is distributed among them in small quantities and you barely notice it at all, certainly no coherent picture
>>428261I mean look very closely and the entire picture is made up of these circles in squares.What if each of those squares turns into one pixel in the original thumbnail so the trick is to average each of those squares by cutting out a bit in each until the 'average' is the pixel you do want. once you know how it translates you can write a program to do it all for you.i don't know anything so what's the code 4chan uses to resize these images? how does the javascript work?
>>428261so if you look at the code on this page, it doesn't do anything with javascript. your computer isn't doing a thing. it actually has two separate files... one of the files is the thumbnail, and the other is the larger one. you click and it changes which image it shows you. That's it.Which means when you upload a picture, there's some code running on 4chan servers that takes that image, shrinks it into an appropriate sized thumbnail, and then displays it.Whatever program they are using, obviously someone has figured out a way to get it to encode a completely different image as the thumbnail. This also means that the original file that exploits the 4chan thumbnail maker program, is destroyed once this gets posted. it splits into thumbnail, and non thumbnail, and you never get to see the original file to inspect how it does it.the real question is how does 4chan convert an image to a thumbnail? is it using some popular software? did they write their own in C or something? it would have to be pretty damn fast and bare bones to handle 4chan or they'd waste so much resources.you'd have to now understand some low level stuff about how an image could be translated into a thumbnail. like what EXACTLY happens.
>>428300This isn't really about how 4chan creates thumbnails. Both the image of the girl and kojima exist in the same image, using a color dithering trick.Now, normally when viewing this image, you'll see both images layered on top of eachother (although it's easier to see the girl than it is to see kojima), but for some reason, when seeing the image on a web browser, you'll only see kojima.I'm assuming this exploits something about the way browsers render images, but I haven't quite figured it out yet.
>>428314I think it has to do with alpha channels
testing with OC
>>428371Fucking how
>>428373obviously didn't get it completely right
will it work better with square images
>>428376try it with the resolution of the original image
>>428261yesjust googleits prolly stupidly easy
>>428400Google search results are trash now.
/g/tard here, there was a thread awhile back where some scripts were shared, I saved 2 to play around with.Here is the first# Title -- Fake Thumbnails# Purpose -- Take 2 image files (png) as input and output 1 image file, this file will have the contents of the first argument andthe thumbnail of the second argument# Explaination -- The website 4chan is an imageboard, you can post images along with text, these images are shown next to the textin a thumbnail, when you click on the thumbnail the full image is loaded.# usage -- ./fakeThumbs WantedImage.png WantedThumbnail.png outputName.png[ -z "$1" -o -z "$2" ] && echo "Need 2 input images." && exit 1[ -z "$3" ] && out="out.png" || out="$3"ffmpeg \ -loglevel 'error' \ -y \ -i "$1" \ -i "$2" \ -filter_complex \ "`echo \ 'color=c=black[mask];' \ '[mask][0:v]scale2ref[mask][main];' \ '[1:v][main]scale2ref[scnd][main];' \ '[mask]drawgrid=w=2:h=2:c=white,format=rgb24[mask];' \ '[main]colorlevels=romin=0.01:gomin=0.01:bomin=0.01' \ ':romax=0.21:gomax=0.21:bomax=0.21,eq=gamma=10.0,eq=gamma=1.4' \ ',format=rgb24,split[main][temp];' \ '[scnd]colorlevels=romin=0.0:gomin=0.0:bomin=0.0' \ ':romax=0.8:gomax=0.8:bomax=0.8,eq=gamma=0.7,format=rgb24[scnd];' \ '[temp][scnd]blend=all_expr='"'B - 0.33*A + 84'"',format=rgb24[scnd];' \ '[main][scnd][mask]maskedmerge[vout]'`" \ -frames:v 1 \ -c:v png \ -f image2 \ -map '[vout]' \ - | \convert \ - \ -set 'gamma' '0.027' \ -define 'png:include-chunk=none,gAMA' \ "$out"
And the second# Author -- Anonymous 01/27/22(Thu)18:07:23 No.85420758# Title -- Fake Thumbnails# Purpose -- Take 2 image files (png) as input and output 1 image file, this file will have the contents of the first argument andthe thumbnail of the second argument# Explanation -- The website 4chan is an imageboard, you can post images along with text, these images are shown next to the textin a thumbnail, when you click on the thumbnail the full image is loaded.# usage -- ./fakeThumbs WantedImage.png WantedThumbnail.png outputName.pnghigh="$1" # High image (full-size original view)low="$2" # Low image (thumbnail) (should be the same size)output="output.png"[ ! -z "$3" ] && output="$3" # Output imagesize=$(convert "$high" -format "%wx%h" info:)convert "$high" -alpha off +level 3.5%,100% -gamma 20 high_gamma.pnglow_gamma="-alpha off -gamma 0.8 +level 0%,77%"convert \( "$low" $low_gamma \) high_gamma.png \ -compose Mathematics -define compose:args='0,-0.33,1,0.33' \ -composite low_adjusted.pngconvert low_adjusted.png high_gamma.png -size $size pattern:gray25 -composite \ -set gamma 0.022727 -define png:include-chunk=none,gAMA "$output"rm high_gamma.png low_adjusted.png
>>428458testing this script
>>428459testing this script
>>428459>>429089this one matches originals betterthx for sharing
>>429088cant decide which one i like more
def like the second one you made more, i like the light blue as opposed to the darker blue. The original photo op posted looks really good tho, you do not see the dots in it at all and you are totally caught off guard, the photos produced from anons script very dotted/pixelated
>>428458>>428459This script is only for linux?
They are messing with you.
>>430058Nope, I changed the extension name to png and it worked in Chrome but when I uploaded it to 4chan it changed the extension.>>430054says ffmpeg, Idk, I guess it works with Windows.Never needed ffmpg, maybe I should introduce myself with it anyway.
>>430059The second script doesn't have ffmpeg. I made a *.bat file but it returns errors. Why do they post scripts without any detail?
