>>4824580
Yes, I am investigating. I was hoping some other anons might post some of their results. It's a fuckton of work to do all by myself.

For the autism of it all, I posted this >>>/an/4739913

The change in filesize on the post reminded me to check some of the stats. picrel shows:

middle: original img properties on my HDD; I saved it as a progressive 99% JPEG. (the subsampling originally was 2x2, and remains so in the downloads)

right: D/L'd WITHOUT the ?arglebargle hack to see native stats and how it might be expected to be saved to an archive service

left: WITH the ?arglebargle hack

I deliberately stripped out all EXIF info and used the 99% & progressive JPEG settings For Reasons so I could compare later to other settings and other file formats. Surprisingly, the progressive JPEG setting was stripped.

Next, the size on disk was increased by almost 1/6th on both the D/Ls over the original ... maybe due to not using the progressive setting? As far as "compression" goes, WTF the JPEG was INCREASED in size, not decreased. Dunno. Weird. But, the load time changed from 250 milliseconds for the original to 100 ms for the two downloads. The Current Memory Size (Win7/IrfanView) remains identical for all three files.

Also note, my upload was to 4channel (blue board) rather than 4chan (red board) ... even though the root domain in the URL stays the same. Dunno if this is a factor, but keep an eye on it.

picrel stats on my HDD:
optimized level 9 lossless *.png
no DPI
2.07 MPixels
16.7 million/24-bit color
224296 unique colors
disk size 2.10 MB (2,206,555 Bytes)
current mem size 5.93 MB (6,220,840 Bytes)
loaded in 94 ms

For the home players who want to see what /hr/ did to that image.

What software & systems do other anons use to analyze their images? What stats are available?

We need to stop referring to this as a "compression," though. Smaller filesizes are not always the end result.

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/hr/

Thread:

4chan has been compressing uploaded images since last year.Please read this thread for more information:…

4chan has been compressing uploaded images since last year.
Please read this thread for more information:…