OpenCV Reinstalled on Computer Phosphene

One of the things I needed to do a few months ago, was a complete reinstall of software on a computer which was named ‘Phoenix’, but which had suffered from a hard-drive controller failure, so that it needed to be resurrected as the computer ‘Phosphene’. Both times that hardware had Debian / Stretch installed, even though the first time it was not an official Kanotix install. The second time it was.

When I need to reinstall the O/S, I also need to install much software again. And one piece of software which I’ve been focusing on somewhat in recent days, is “OpenCV“.

‘OpenCV’ is a library and a series of header files, and a set of Python modules, and a Java Interface, that specialize in Computer Vision, which could therefore be classified as a rudimentary AI, although it should be said that This form of AI is still of such a variety, that the computer is only performing remarkably complicated calculations, to be able to do things, which were not feasible only a few decades ago. It provides Image Recognition. Because of the way I am, I value having many computing resources installed, even if I rarely use them. OpenCV would be one such resource.

What tends to happen on Debian-based platforms, is that the version of OpenCV available from the package manager is a somewhat old version – in the case of Debian / Stretch, v2.4.9 – which is only important to install the library packages for, not the ‘-dev’ packages, and the former because the library packages are also dependencies of many other packages, which use OpenCV in the background, but not in any way that the user would want to write his own applications with.

What I additionally did, was to install v4.1 from the OpenCV Web-site, from source-code, and this seems like a good move because v4.1 is rumoured to be easier to write programs with, than v3.2 was, especially if the power-user does not want to end up shoulder-high in low-level code, to do many of the uninteresting parts of what his application needs to do, to be user-friendly.

But then, before writing our own applications with OpenCV, what we might also want is a demo program, that just shows users what the capabilities of this library and of this SDK are. And so the main program to do this with is called “OpenCV Demonstrator“. This could be a way to intrigue ourselves, as well to show off what our computers can do, maybe to friends?

 

Screenshot_20190610_082145

 

But here I ran into a bit of a snag. ‘OpenCV Demonstrator’ has only been compiled, by its author, as an application that uses OpenCV 3.2, and according to examination of my blog entries from before the reinstall, was compatible with v3.4. It’s not compatible with v4.1, even though v4.1 is more powerful. Whenever there is a major version update, let’s say from 3 to 4, applications built against one version will no longer run, when compiled against the next version. But I wanted that Demonstration Program. And so the following is what I did:

Continue reading OpenCV Reinstalled on Computer Phosphene

Speculation about a Hypothetical, Alien’s Culture

A concept which has captured Human imagination for decades, is the possibility of life on other planets, presumably orbiting other stars, than our own Sun. And the first, obvious question people might ask is, ‘If aliens – i.e., ETs – exist, which Solar System – i.e. Star – might they be living on?’ as well as ‘Have they in fact, ever traveled to our solar system?’ What I’d like to do with this posting, is to direct my own thinking sideways, into a mode more speculative, than anything I normally blog about: ‘What culture / societal / ideological ordering might they have, if they exist at all, through which they would judge our society?’

And I’d just like to point out a brief observation, about reported alien abductions: The people who were abducted, at least according to initial reports in the 1970s etc., seemed to detail being taken into rooms on-board spacecraft, which were remarkably devoid of controls. In the 1970s, our aircraft and other platforms had many instruments, buttons, dials, switches and so forth, consistently with our own level of technology, or due to our lack of technology, which prevented us from having glass cockpits, as we do today. And I can really think of only two possible reasons, why the abduction reports would be different in this detail:

  1. No abductions may actually have taken place, and the people reporting them may have had little imagination, as to what the future, or the inside of a spaceship is supposed to look like, or
  2. The aliens live in bare rooms, that don’t have levers, buttons, switches, etc.. They may have illuminated surfaces though, that are more than just illuminated surfaces…

Continue reading Speculation about a Hypothetical, Alien’s Culture

Photometrics and Face Recognition

A question which I’ve recently stumbled in to, is whether computer face recognition should be based on some sort of Fourier Transform of an image, which also refers to spatial frequencies, or on the Photometric placement of key features belonging to the face in 3D.

This photometric analysis of geometries was once referred to as ‘Photo-Modeling’, or, ‘Photo-Grammetry’.

There is a good chance that either method of face recognition can be made to work. But in the case of the photometric approach, there are two caveats which I don’t see news sources as mentioning:

  1. Photometrics requires a fairly high-resolution image of one face, while the methods based on spatial frequencies can work with low resolutions and poor-quality images,
  2. AFAIK, In order for photometrics to proceed in a completely automated way, footage or images of the subject need to be recorded, from at least three camera-positions, preferably in such a way that the lighting matches exactly. In this regard, modeling points that belong to the face is similar today to how it was a few decades ago, when a Hollywood Laser needed to paint grid-lines on the face, but is possible today without the grid-lines.

Hence, if a group has in fact used photometrics on a face, because they had 3 camera-positions, they’d also be in a position to display only one of the camera-positions, with the required points being positioned automatically. If the group presents the resulting overlay by itself, they may be confusing some viewers by omission.

In other words, the subject could be asked to look directly at one camera-position, that is obvious to him, but there could have been two additional camera-positions, that he was not aware of.


 

(Updated 09/15/2018, 17h35 … )

(As of 09/06/2018 : )

Alternatively, I am aware that ‘3D Cameras’ exist, which obtain a depth-map of the scene in front of them, due to an additional laser-emitter, that has been positioned in a way offset from the main camera axis.

Continue reading Photometrics and Face Recognition