29a.ch
29a.ch · Personal blog · on HN since 2009
Jonas Wagner publishes browser-based graphics experiments, the Forensically photo analysis tool, and the smartcrop.js image cropping library.
What HN saysHN links it for visual toys like Neonflames, WebGL demos with slides explaining them, photo forensics, and smartcrop.js.
29HN people shared it
12linked it in comments
20stories submitted
290story points
5 years agolast shared
2009people per year2026
Most-shared posts
- 1Html5 Neonflames4 people · 120 points · first shared 2011 · 26 comments on HN
- 2Forensically, free online photo forensics tool4 people · 6 points · first shared 2015 · 1 comments on HN
- 3Normal Mapping with Javascript and Canvas Tag4 people · 2 points · first shared 2010 · 1 comments on HN
- 4Image Error Level Analysis with HTML53 people · 7 points · first shared 2012 · discussion on HN
- 5Two line fix to speed up canvas performance on iPhone42 people · 63 points · first shared 2011 · discussion on HN
- 6JS Wars1 people · 34 points · first shared 2009 · 10 comments on HN
- 7Smartcrop.js (2014)1 people · 33 points · first shared 2016 · 9 comments on HN
- 8Forensically, Photo Forensics for the Web (2015)1 people · 12 points · first shared 2021 · 1 comments on HN
- 9Minecraft-like voxel world demo in javascript and WebGL1 people · 3 points · first shared 2012 · discussion on HN
- 10HTML5 Canvas Fluid Simulation1 people · 3 points · first shared 2013 · 2 comments on HN
- 11WebGL Terrain experiment rendering the island Maui with fog and water1 people · 2 points · first shared 2012 · 2 comments on HN
- 12WebGL error statistics1 people · 1 points · first shared 2011 · discussion on HN
- 13Navier Stokes Equations based Fluid Dynamics1 people · 1 points · first shared 2013 · discussion on HN
- 14WebGL Iceberg demo1 people · 1 points · first shared 2011 · discussion on HN
- 15Image Error Level Analyser1 people · 1 points · first shared 2014 · discussion on HN
What HN people wrote when they linked it
jw1224 · 2020-07-29
I played with this for ages in the peak of an LSD trip once... It was quite the experience.
Some other fun "art toys" I like are:
1. https://29a.ch/sandbox/2011/neonflames/
2. https://codepen.io/davidpanik/full/myMrLx/
3. https://codepen.io/jackrugile/full/DGenc
Nanite · 2017-06-30
This one by any chance? https://29a.ch/photo-forensics/#forensic-magnifier
tyingq · 2017-05-28
Not much newer, but I like the in-depth slides that cover how it was done:
The effect: https://29a.ch/sandbox/2012/terrain/
The slides that explain: https://29a.ch/slides/2012/webglwater/
deepnet · 2016-03-04
Deferring a Phong shader gives 'good enough' dynamic lighting for 2D dynamic sprite lighting and is fast.
https://29a.ch/2010/3/24/normal-mapping-with-javascript-and-canvas-tag
chnx · 2015-11-27
smartcrop.js is interesting.
https://github.com/jwagner/smartcrop.js/
http://29a.ch/sandbox/2014/smartcrop/examples/testsuite.html
kevin · 2015-06-12
Pretty cool, but I got lost in the credits.
"Inspired by and based on Jonas Wagner's work which is based on this paper."
http://29a.ch/2010/2/10/hand-drawn-lines-algorithm-javascript-canvas-h…
https://www.rug.nl/research/portal/files/2743863/2008ProcCAGVIMeraj.pd…
From the abstract:
"We found that an observational analysis of human lines made a bigger impact on the algorithm than a statistical analysis. "
Can someone explain what that means?
Also, the University of Groningen is located in the Netherlands. Cool. Thanks Dutch computer scientists!
Havoc · 2014-02-19
The name doesn't ring a bell, but judging by the pic its this stuff:
http://29a.ch/2012/4/15/image-error-level-analysis-with-html5
sp332 · 2011-07-12
Is that similar to this hack for faster canvas rendering on iPhone http://29a.ch/2011/5/27/fast-html5-canvas-on-iphone-mobile-safari-perf… or is it completely different?
bd · 2010-05-05
Here is a very similar effect in canvas:
http://29a.ch/2010/3/24/normal-mapping-with-javascript-and-canvas-tag
Zakharov · 2015-05-24
There's Neonflames: http://29a.ch/sandbox/2011/neonflames/
aleyan · 2013-11-08
Preface: I have no experience in 3D graphics.
This is a very cool technique. I have been thinking about how to generate normal maps for traditionally drawn 2D images ever since seeing the normal mapped canvas demo[1]. This seems to be an answer.
Drawing lighting profiles that are coherent however does not seem simple. One of the uses of this technique "Depth maps for stereoscopic 3D" appears much more complicated to me that drawing a depth map by hand in the first place. I drew a depth map for my drawing Starry Venice[2] as a step in making it into a wigglegif. Drawing multiple correct light profiles to generate the depth map for a scene such as Starry Venice seems almost impossible to me. This is far from the base use-case, but still.
It will be interesting to see how forgiving the creation of the normal map will be on imperfect light profile inputs. Also, it will be interesting to see if any artists who are masters of this technique will emerge.
[1] http://29a.ch/2010/3/24/normal-mapping-with-javascript-and-canvas-tag
[2] http://fooladder.tumblr.com/post/61216111704/starry-venice
imaginenore · 2015-10-14
> the test cases look just as good as I could do
I think you can do better than it did on these:
http://29a.ch/sandbox/2014/smartcrop/examples/images/65344435.jpg
http://29a.ch/sandbox/2014/smartcrop/examples/images/65309527.jpg
http://29a.ch/sandbox/2014/smartcrop/examples/images/65443239.jpg
http://29a.ch/sandbox/2014/smartcrop/examples/images/28155975.jpg
http://29a.ch/sandbox/2014/smartcrop/examples/images/64843515.jpg
http://29a.ch/sandbox/2014/smartcrop/examples/images/64765319.jpg