Comments on: Adaptive thresholding experiment

By: Adaptive thresholding in FLARToolkit « Fréderic Cox

Adaptive thresholding in FLARToolkit « Fréderic Cox — Mon, 08 Jun 2009 20:36:32 +0000

[...] (one value for all pixels). Saqoosha (the japanese creator of the FLARToolkit) did a little experiment with adaptive thresholding and based on his code I altered the FLARRasterFilter_BitmapDataThreshold [...]

By: JActionScripters - Flashers from Japan | Leichtgewicht

JActionScripters - Flashers from Japan | Leichtgewicht — Tue, 19 May 2009 23:30:30 +0000

[...] Its amazing how much flow those guys have right now: beside the daily updates at the Spark Project, their own blog posts in japanese and the work on new projects, they produced in the 4 days its online already about 10 quite interesting blog posts about things like fractal painting, lcd effect, vector multiplication or adaptive thresholding. [...]

By: イナヅマtvログ » Flash, Actionscript, 日本最強のブログ誕生

イナヅマtvログ » Flash, Actionscript, 日本最強のブログ誕生 — Mon, 18 May 2009 21:44:53 +0000

[...] Study – Recreating LCD Panels / Trinitron Like Matrices by Jun Saburi Adaptive thresholding experiment by [...]

By: makc

makc — Mon, 18 May 2009 10:32:39 +0000

that was not the reduction I was talking about, but any way – what choice do we have? if the marker is lost, the entire image area has to be searched. in this case, you can have better frame rate by looking into part of whole image at a time, but this also means you will have several frames with marker undetected while still being there. or, you could use global threshold based on last known local threshold value at the marker area, but there is fairly good chance that you will not find marker with it any way. finally, what artoolkitplus folks did – randomize threshold until you find something – good and simple, but again, you have frames with marker undetected even though it is there.

By: Saqoosha

Saqoosha — Mon, 18 May 2009 06:39:35 +0000

> mack

I saw your code and tested. Reducing processing area is very efficient way. but the result image is more complicated than constant thresholding’s. so it takes mare cpu time to labeling it. it’s not problem during when marker is detecting, but when lost the marker, search area become very large and takes long time to detect.

http://saqoosha.net/en isn’t proper url. I fixed to redirect to http://saqoosha.net/en/ . Thank you!

By: makc

makc — Mon, 18 May 2009 05:24:46 +0000

One obvious optimisation would be reducing dimensions of image with draw (,matrix) instead of blur, but still the main problem remains to be increased amount of details that FLARToolKit gets to deal with, so the problem is not really in the filter.

Btw, what happened to http://saqoosha.net/en?