Friday, April 10, 2009

Processing 1.0 can be used for Signal Processing as well?

Our video processing team is planning to use Processing 1.0 for video processing(real time). At some point video processing team and signal processing team would need to collaborate. I found that Processing 1.0 might be used even for signal processing, not sure though.

I found some links , which would be worth checking and I emailed Signal Processing Team.

http://cnx.org/content/m13045/latest/
http://cnx.org/content/m13046/latest/
http://cnx.org/content/m10087/latest/
http://cnx.org/content/m13047/latest/

I believe using same tools for both video and signal processing would help when both signal and video team collaborate.

Talked to Peter about the decision of using API

Peter and me talked about "which api to use?"

Right now we do not know for sure how complex analysis we might need and do not know the effects of resolution. And we think both processing 1.0 and imageJ can be added to project and we can use whichever fits our requirement as we go with the project.

Processing 1.0 VS ImageJ

Research from our Visual Team makes us believe that,

For real time video capturing and image processing (if complex analysis not required) processing 1.0 can be a quicker and simple solution to extract very basic information from video and frames.

For complex analysis ImageJ seems ultimate solution. ImageJ is not capable of real time video capturing but strong tool for offline use.

Rectification - What does Michal meant ? Got Answer

In our first weekly meeting we also got confused with the word "Rectification"

Peter emailed Michal, Michal and Daniel replied and the summery is , if I understood..

"Remove as many things required to retrieve all the information we need to extract from the Frames, say finger tips (points, centroid, time-stamp)"

And would be better not to emphasize on the word "Rectification" rather retrieve required information correctly.

Here is the Message on Rectification and reply from "Michal"

Our First Visual Team meeting

We did couple of things on our first meeting. I brought my video camera and the tactile map to have some sample videos.

1. Did video on the Tactile map using blind folded person
Videos on YouTube

2. Made a plan on weekly basis

3. Distributed tasks

4. Talked about basic ideas of doing the image processing as thresholding, rectification, use of k-mean algorithm, etc.

Friday, April 3, 2009

Point Stream ??

What should be the point stream ? An 2D array for point coordinates p(x,y) ? The image rectification says it converts 2D space to 1D space and if we want rectification then what we are gonna get?

Well again there is built in loadpixels() function in Video library in processing 1.0 which can load(save) pixels into video_frame.pixels[] array and its one dimensional. Seems like video library of processing 1.0 automatically rectifies before loading pixels as pixels[] is an one dimensional array.

So what we should have in our point stream ? 1D pixels ? or 2D points?

Rectification confusion again

After some googling on Image rectification, I find this

Why Rectification?
To change a 2-D search problem in general into a 1-D search problem

How Rectification?
Basic idea: The rectified images can be thought of as acquired by a new stereo rig, obtained by rotating the original cameras around their optical centers.


Exactly what Micheal means with Image Rectification?