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"The program should, in some way, expand the concept of what computer paint programs are, as well as what mark making can be."

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Omar Rizwan @omar

do u ever watch someone take a
picture of someone else's phone
screen and feel the angel of omar
give a nod of approval

[heart react]

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Omar Rizwan @omar

Rekt

The Truth

Source code in opencv

The truth is, as usual, in the source code of opencv. Typically, we see the relevant code blocks,

x0 = x = (x - cx)*ifx;
y0 = y = (y - cy)*ify;

// compensate distortion iteratively
for( j = 0; j < iters; j++ )
{
double r2 = x*x + y*y;
double icdist = (1 + ((k[7]*r2 + k[6])*r2 + k[5])*r2)/(1 + ((k[4]*r2 + k[1])*r2 + k[0])*r2);
double deltaX = 2*k[2]*x*y + k[3]*(r2 + 2*x*x);
double deltaY = k[2]*(r2 + 2*y*y) + 2*k[3]*x*y;
x = (x0 - deltaX)*icdist;
y = (y0 - deltaY)*icdist;
}
This confirmed my guess and the math equations in the opencv tutorial is not correct.

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Omar Rizwan @omar

feel like the older i get the more i'm like, nothing on the internet can be relied on to last at its original location, and people should copy and paste / blockquote as much as possible so that the information is more likely to survive in at least 1 place https://mastodon.coffee/@shammers/111574867456966246

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Omar Rizwan @omar

It was cool although I felt like the character who they put in a movie who
doesn't know anything so that the audience can listen to the other
characters explain everything to them 10:43 PM

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Omar Rizwan @omar

I've been getting back on the RFID train lately with pretty good results, feels like I've broken through where I was stuck on this refactor a couple months ago --

plot of rfid output (red lines showing how RN16 was parsed properly)

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Omar Rizwan @omar

https://www.cs.rpi.edu/~trink/Courses/RobotManipulation/lectures/lecture6.pdf

Why representing rotations is hard.

e Rotations do not commute.

e The topology of spatial rotations does not permit a smooth
embedding in Euclidean three space.

Lecture 6. Mechanics of Manipulation -

Choices

More than three numbers
e Rotation matrices
e Unit quaternions. (aka Euler parameters)
Many-to-one
e Axis times angle (matrix exponential)
Unsmooth and many-to-one
e Euler angles
Unsmooth and many-to-one and more than three numbers
e Axis-angle

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Omar Rizwan @omar

Rotations day today

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Omar Rizwan @omar

https://kd.hs-mainz.de/shop/the-worlds-writing-systems-poster/

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Omar Rizwan @omar

"The need for a fortran compiler was a big part of the original rationale for the divide of numpy and scipy when they replaced numeric. Numpy was meant to be the lighweight/core version of things, and scipy was the full-fledged environment."

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Omar Rizwan @omar

C10G in 2028?

The C10M problem

It's time for servers to handle 10 million simultaneous connections, don't you think? After all, computers now
have 1000 times the memory as 15 years ago when the first started handling 10 thousand connections.

Today (2013), $1200 will buy you a computer with 8 cores, 64 gigabytes of RAM, 10-gbps Ethernet, and a
solid state drive. Such systems should be able to handle:

- 10 million concurrent connections

- 10 gigabits/second

- 10 million packets/second

- 10 microsecond latency

- 10 microsecond jitter

- 1 million connections/second

Such systems already exist. We call them "hardware" or "devices". But in recent years, devices have become
just software running on general purpose computers. Rip open a network device and you might find a personal
computer inside. The limits of scalability aren't our hardware, but the software, specifically, the operating
system.

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