Faking a JPEG • Hacker News Board

Re: Faking a JPEG

#31

Post by jandrese » Sat, Jul 12, 2025, 5:15 AM UTC

I wonder if you could mess with AI input scrapers by adding fake captions to each image? I imagine something like:

    (big green blob)

    "My cat playing with his new catnip ball".


    (blue mess of an image)

    "Robins nesting"

Re: Faking a JPEG

#32

Post by 112233 » Sat, Jul 12, 2025, 5:42 AM UTC

So how do I set up an instance of this beautiful flytrap? Do I need a valid personal blog, or can I plop something on cloudflare to spin on their edge?

Re: Faking a JPEG

#33

Post by ffsm8 » Sat, Jul 12, 2025, 5:48 AM UTC

112233 wrote: post #32

So how do I set up an instance of this beautiful flytrap? Do I need a valid personal blog, or can I plop something on cloudflare to spin on their edge?

It's a flask app, he linked to it

https://github.com/gw1urf/spigot/

Re: Faking a JPEG

#34

Post by bigiain » Sat, Jul 12, 2025, 5:55 AM UTC

bschwindHN wrote: post #3

You should generate fake but believable EXIF data to go along with your JPEGs too.

Fake exif data with lat/longs showing the image was taken inside Area 51 or The Cheyenne Mountain Complex or Guantanamo Bay...

Re: Faking a JPEG

#35

Post by bigiain » Sat, Jul 12, 2025, 5:57 AM UTC

BlaDeKke wrote: post #23

maxbond wrote: post #19

Earlier quoted context omitted.

Encoded JPEG data is random in the same way cows are spherical.

Cows can be spherical.

And have uniform density.

Re: Faking a JPEG

#36

Post by superjan » Sat, Jul 12, 2025, 6:12 AM UTC

There is a particular pattern (block/tag marker) that is illegal the compressed JPEG stream. If I recall correctly you should insert a 0x00 after a 0xFF byte in the output to avoid it. If there is interest I can followup later (not today).

Re: Faking a JPEG

#37

Post by levzzz » Sat, Jul 12, 2025, 6:15 AM UTC

jandrese wrote: post #31

I wonder if you could mess with AI input scrapers by adding fake captions to each image? I imagine something like: (big green blob) "My cat playing with his new catnip ball". (blue mess of an image) "Robins nesting"

[dead]

Re: Faking a JPEG

#38

Post by extraduder_ire » Sat, Jul 12, 2025, 6:47 AM UTC

creatonez wrote: post #27

EspadaV9 wrote: post #7

I like this one https://www.ty-penguin.org.uk/~auj/spigot/pics/2025/03/25/fa... Some kind of statement piece

For the full experience: Firefox: Press F12, go to Network, click No Throttling > change it to GPRS Chromium: Press F12, go to Network, click No Throttling > Custom > Add Profile > Set it to 20kbps and set the profile

Good mention. There's probably some good art to be made by serving similar jpeg images with the speed limited server-side.

Re: Faking a JPEG

#39

Post by electroglyph » Sat, Jul 12, 2025, 7:04 AM UTC

russelg wrote: post #28

bschwindHN wrote: post #3

You should generate fake but believable EXIF data to go along with your JPEGs too.

They're taking the valid JPEG headers from images already on their site, so it's possible those are already in place.

there's no metadata in the example image

Re: Faking a JPEG

#40

Post by Dwedit » Sat, Jul 12, 2025, 7:20 AM UTC

jandrese wrote: post #31

I wonder if you could mess with AI input scrapers by adding fake captions to each image? I imagine something like: (big green blob) "My cat playing with his new catnip ball". (blue mess of an image) "Robins nesting"

A well-written scraper would check the image against a CLIP model or other captioning model to see if the text there actually agrees with the image contents.