Archives for category: Research Algorithms

Short update this week!

After having so much trouble with OpenCV for C++, I started exploring a few other options.  I started by looking at OpenCV for Processing.  Unfortunately, after installing the OpenCV libraries, I was unable to run any of the sample code.  Many other frustrated Windows users had experienced the same problem I had, and I found no solutions.

The Processing website had several other libraries for blob detection and other vision-related processes.  I installed a few of these examples and was able to use the code.  These examples were much more light-weight than OpenCV and would most likely be sufficient for my purposes.

Now, I’m in the process of reworking blob detection examples to detect hands.


This week was pretty frustrating on the whole, but I made some last-minute advances!  Installing OpenCV for C++ was a pain and now it seems that OpenCV is having problems accessing my webcam (it was working with a previous compilation).  Here’s a summary of what went on:

Installing OpenCV for C++

Because OpenCV with Python was 1) potentially slow and 2) starting to become more cumbersome by the minute, I decided to switch to using OpenCV with C++.  One caveat is that I don’t actually know C++ (not to mention I haven’t used OpenCV), but I have access to people who OpenCV professionally (yay!).

With some help, I got OpenCV installed (which included installing MingGW, helping me use CMake, and building and compiling).  After all of that I tried to run a sample face tracking program.  Unfortunately, my webcam is showing up as a black box!  The webcam was working previously, so I need to do some more investigation…

WebCam with Scratch-like languages:

I spent a lot of time looking at Squeak, being confused, and looking at other blocks-language alternative.  Integrating video into a Scratch-like language seemed really intimidating, and I was worried that it would be impossible for me to complete by myself.  However, after some searching, I found a solution (Panther, a Scratch extension).  Here are all of the options I considered:

OpenBlocks -A Java-based blocks language generator released by MIT.  OpenBlocks seemed very versatile and (I’m assuming) you could use it to create a visual representation of any other language.  I thought I might be able to use a more familiar language, handle video input/machine learning, and use OpenBlocks to create a nice blocks version.  HOWEVER, after downloading OpenBlocks (and emacs for editing purposes), I did not have much luck.  I also found OpenBlocks confusing – they had some Java Docs, but there was so much to go through.  Ick.

Squeak – Ahh Squeak.  Squeak is such a strange language (at least to me), so I was at a total loss when thinking of how to integrate video input.  The most recent version of Squeak is version 4.3, but Scratch runs on a modified version of Squeak 2.8.  There are several pre-written Squeak libraries, some even for video, but they were spottily documented and none worked with Squeak 2.8!

Scratch – I spent some time looking at the latest version of Scratch (and its Squeak code).  Scratch offers some webcam support.  Users can take a picture with a webcam and use the image as a sprite’s costume.  The only downside is that you cannot access the webcam in code or do any kind of streaming.  Still, I figured if you could take a picture with a webcam, there must be SOME support for streaming video.  Now I just need to have some convenient blocks for USING this functionality…which brings me to Panther.

(As a side note, I also made a simple block in Scratch)

Panther – Panther is an extension of Scratch that integrates more advanced features – including manipulation of the webcam!  Panther also lets you do file I/O, which may be useful for getting data to/from OpenCV.  I still have to explore Panther a lot more, but I think it’s a great platform for this project!

Here’s an example of me using webcam data in a Scratch-like program:

The blocks I used:

To summarize…

Things accomplished:

  • Install OpenCV for C++
  • Learn to make a block in Scratch
  • Find a way to integrate webcams and a Scratch-like language (WHEW)
  • Get a decent text editor for C++ programming (Notepad++ with added modules)

Things to do:

  • Get OpenCV to work with my webcam
  • Re-implement skin detection in C++
  • Use blob tracking in C++
  • Start working on gesture recognition
  • Send data from C++ program to Panther
  • Create more custom blocks in Panther