+thebruce0 Posted November 30, 2020 Share Posted November 30, 2020 19 hours ago, mustakorppi said: On 11/28/2020 at 8:31 PM, fizzymagic said: So, actually, it would not break any puzzles Wanna bet? I can also vouch for at least one puzzle that would definitely be broken by converting to webp Quote Link to comment
+fizzymagic Posted November 30, 2020 Author Share Posted November 30, 2020 4 hours ago, thebruce0 said: I can also vouch for at least one puzzle that would definitely be broken by converting to webp Yeah, I had not thought about the "append-a-zip-file-to-a-jpeg" puzzles. Those would break. Maybe (here's an idea) leave them in the format in which they were uploaded! 3 1 Quote Link to comment
+mustakorppi Posted November 30, 2020 Share Posted November 30, 2020 7 hours ago, fizzymagic said: I had not thought about the "append-a-zip-file-to-a-jpeg" puzzles The attached gif contains hidden coordinates. Here's the same image in webp, converted using the gif2webp tool from newest libwebp. It is smaller than a progressive jpeg would be, but it breaks the "puzzle" just the same. Quote Link to comment
+ecanderson Posted November 30, 2020 Share Posted November 30, 2020 All I'm seeing with Firefox 83.0 is blank white on both this page and the Dropbox page. Dropbox starts to produce an image (I see the gray/white checkered image space), but then just white. 1 Quote Link to comment
+fizzymagic Posted December 1, 2020 Author Share Posted December 1, 2020 (edited) 11 hours ago, mustakorppi said: The attached gif contains hidden coordinates. Here's the same image in webp, converted using the gif2webp tool from newest libwebp. It is smaller than a progressive jpeg would be, but it breaks the "puzzle" just the same. You'll note that I did not mention paletted images in my post. For whatever reason, GIFs are being preserved by the current system. WebP has no alternative to animated GIFs and I don't know if it has a paletted mode. Conversion would require preservation of the palette, for both paletted PNGs and GIFs. Which is why just leaving the images alone is the optimal solution! I am fine with size reductions if the images exceed some maximum storage size, as long as it is make clear on the image upload page. Right now, the most violence is being done to PNG images, although appending data to jpegs probably breaks as well. Edited December 1, 2020 by fizzymagic Quote Link to comment
+mustakorppi Posted December 1, 2020 Share Posted December 1, 2020 2 hours ago, fizzymagic said: WebP has no alternative to animated GIFs and I don't know if it has a paletted mode. Webp does support animation and from what I understand it has some kind of a palette mode, but I’m not aware of any tools that would let you mess with it. 4 hours ago, ecanderson said: All I'm seeing with Firefox 83.0 is blank white Hence, ”hidden coordinates” As fizzymagic hinted at, that gif image has two colors in its palette. Both of the colors are currently titanium white but if you mix in some van dyke brown with the other one, you’ll get happy little treesthe coordinates. Quote Link to comment
+sernikk Posted December 2, 2020 Share Posted December 2, 2020 (edited) Geocaching.com is still treating Waymarking.com as an enemy and is not allowing to paste any images from there. As an example, it is impossible to use the official logo: https://www.Waymarking.com/images/logo.gif as an image. Shouldn't this be fixed by now? I remember the discussion about it. Edited December 2, 2020 by sernikk Quote Link to comment
+mustakorppi Posted December 2, 2020 Share Posted December 2, 2020 5 hours ago, sernikk said: Geocaching.com is still treating Waymarking.com as an enemy and is not allowing to paste any images from there. As an example, it is impossible to use the official logo: https://www.Waymarking.com/images/logo.gif as an image. Shouldn't this be fixed by now? I remember the discussion about it. The obvious implication is that Waymarking.com places nefarious advertising cookies on people's browsers. Quote Link to comment
+thebruce0 Posted December 3, 2020 Share Posted December 3, 2020 On 11/30/2020 at 1:41 AM, fizzymagic said: Yeah, I had not thought about the "append-a-zip-file-to-a-jpeg" puzzles. Those would break. As would puzzles based on understanding the PNG spec... Quote Link to comment
+sloth96 Posted December 3, 2020 Share Posted December 3, 2020 So does anyone have a list of steganography tools that survive this transcoding? Outguess and silenteye are two that i have seen recently for puzzles. Quote Link to comment
+fizzymagic Posted December 14, 2020 Author Share Posted December 14, 2020 On 12/3/2020 at 12:19 PM, sloth96 said: So does anyone have a list of steganography tools that survive this transcoding? Outguess and silenteye are two that i have seen recently for puzzles. Outguess barely survives anything; silenteye is probably a little better. I don't like using canned steganography that requires (as those do) downloading a program. I much prefer rolling my own that people can figure out how it's done instead. I have recently done some GIF stuff that would survive but I think it might be too difficult as a puzzle until I think of something clever to make it work. Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.