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Searching for: graphics
Stippler: Turning photos into dots [stippler]
Stippler: Turning photos into dots [01108611472]
A few weeks ago, I stumbled over a paper by Adrian Secord describing an algorithm to turn a greyscale image into stipples. Here are the results of my implementation of his algorithm. UPDATE: I added the original photo of Marie, as well as the version that was used as input by stippler.
Stippling with lots of points [01109080625]
crane-out
This image has 12k points. I don't think this many points are practical on the mill, but it looks pretty good onscreen. Screenshot from the stippler software, resized and cropped with gimp.
It's in a frame! [01109127822]
OK, so there are still some problems left. But this is exciting anyway.
Much better results [01109259892]
Serendipitous optimization [01111679069]
An implementation choice in stippler turned out to give near-optimal output for the milling machine
VGA to 'scope display [01113670404]
(M)(L)XY display of a cube
The question on my mind was this: Where do I get a nice, fast DAC to run an XY display? How do I keep it fed with values? I discovered a very simple answer that I hadn't heard of before.
The hardware is dirt simple: Get a VGA to 5 BNC-connector cable. Plug your computer's VGA output into your scope. Now load a specially crafted image in a full-screen viewer
Animated XY display [01113705217]
(M)(L)Not originally a raster game...
It's an old-style "QIX" animation.
Vector "text" display [01113752862]
(M)(L)Simulating a character-cell display
Displaying a message, even.
Working Z-axis [01114736689]
(M)(L)Vector terminal with Z-axis
With a simple transistor, the Z axis works pretty well. The linearity is better now that I'm using some 10b2 tees and terminators (50 ohms) on the X and Y inputs, too.
MAME vector display on the oscilloscope [01114971365]
(M)(L)Asteroids
Yep, it works. Too bad about the low resolution. More game pictures below the fold.
"Dithered" output increases resolution [01114979771]
More vector game screenshots [01115494353]
(M)(L)Battle Zone
I really should mention the website of Jed Margolin which has a lot of information about his time at Atari, including his work with vector games.
Vector patches for xmame 0.94 [software/01115603825]
With this patch applied, xmame 0.94 does vgaxy-style output for display on an oscilloscope in xy mode
vgaxy -- create XY scope displays with your VGA card [software/01115603899]
Software for a virtual terminal and several other toys
XY display update [projects/01117067802]
… less frequently). Apparently the ATI graphics chipset in my laptop is capable of a display of…
a plug for Eagle3D [01117938653]
Flicker and QOOP [01126061732]
Off and on, I'm interested in printing my photography. So today
when I heard about QOOP I decided to take
a look.
glif: generate client-side gif files from javascript [software/01126462511-glif]
It probably won't be the biggest thing since AJAX, but I hit upon the
idea of generating images client-side. The current ways to do this seem to
involve using tables or absolute-positioning of very small DIVs. (See, for
example, http://www.walterzorn.com/jsgraphics/jsgraphics_e.htm) My
technique, which I call glif (for GIF and glyph),
generates a gif-format image on the client side.
One application for this that comes immediately to mind is client-side
generation of sparklines-type images, possibly from an AJAX source.
glif.html is a small demo which draws a sine wave in an image (Known not to work in IE) Update: SparGlif demo
QOOP: My friends' reaction to one of their photo books [01128087897]
I ordered a 16-page photo book from QOOP on the 20th, it was shipped
on the 26th and delivered to me on the 28th. The total cost including shipping
was $20.04. Read on for my reactions and the reactions of my friends.
Response from QOOP (updated with comparison images) [01128382096]
I got a response from QOOP about the perceived problems with my order. Be sure to see the newer entry about this issue.
QOOP -- the final chapter? [01128882221]
After seeing the comparison image I posted earlier, QOOP has thanked me for bringing the resolution issue to their
attention, and offered me a Flickr Pro membership at their expense. I'm
pleased with this outcome.
Two optical illusions [01131390746-two-optical-illusions]
Hershey Vector Fonts [software/01132595691]
Stippler 1.0 source release [software/01133127497-stippler-source-release]
I finally got around to writing my own dithering algorithm, so now
all parts of stippler are under a clear GPL license.
Stippler is software for turning greyscale images into "stippled" images.
I have have discussed it before on my blog.
Stippler is based on the reasearch of Adrian Secord,
but the implementation is my own.
Files currently attached to this page:
stippler-1.0.tar.bz27.9kB
Onscreen Crosshairs in tcl/tk [software/01146347893]
I was staring too long at a screenshot of a graph on some web page, wishing I
could tell if two things lined up. Well, inspiration struck, and this program
was born. Two windows—one that is one pixel wide, and another
that is one pixel tall—are created, and they follow the mouse
around every 1/10 second or so. They're displaced by one pixel so that clicking will hit the underlying window, not the crosshair.
I apologize for the changing colors, since xor isn't available with this simple
method of drawing the lines, it's the only way to be sure to get contrast. I considered making the color depend on e.g., whether SHIFT is pressed, but if Tk provides this information to a window that doesn't have focus, I overlooked it in the manpages.
Tired of missing OpenGL manpages on Ubuntu [01157053957]
The Bayer sensor vs the Foveon sensor (part 1 of 2) [01161569781]
Using synthetic images, I have subjectively compared the
effective resolution of a Bayer and a Foveon sensor with the same number of
photosites.
The Bayer sensor vs the Foveon sensor (part 2 of 2) [01161627308]
(M)(L)cactus
In this part of the article, I present
the images and compare the results to my predictions.
Making a YouTube video of X program [01196105360]
Instructions for recording any X program into a video suitable
for upload to youtube
Cairo-based waveform demo [01218769184]
XO-1 screen simulation [01226934973]
olpcgui.py in action
I failed to resist the new G1G1 program and
ordered myself an XO-1 today. As a lot of geeks are, I'm intrigued by the
screen. Updated: sped up the simulation a bit with a pyrex module.
Canon Digital Rebel XSi (450D) on Linux Ubuntu Hardy 8.04 [01234628660]
cropgui: A Linux GUI for Lossless JPEG Cropping [01235516977]
Cropping a tiny insect
Update: See the newer version of cropgui
Of the pictures from my recent trip I'd like to put online, I've found
that in 75% of the cases where I want to retouch the photo, it's to crop
it and nothing else. Since I shoot in jpeg, it's a lossy process to
load the jpeg in gimp, crop it, and write the result.
But it turns out that debian's jpegtran has a "-crop" flag which
performs lossless cropping of jpeg images as long as the crop is to a
multiple of what the manpage calls the "iMCU boundary", a (usually?) 8x8
block of pixels. This feature was pioneered by Guido of jpegclub.org some years ago.
There's apparently a nice Windows front-end to this program, but I didn't find a Linux one. So I wrote one! It's pretty basic,
but it gets the job done. You can download it below.
CropGUI 0.1.1: now with gtk [01248401946]
Gtk version of cropgui
Earlier this year, I released a
program for lossless cropping of jpeg images. This week, based on
feedback from Ingrid, I ported the program to gtk (it originally used
tkinter).
StippleGen 2—Stippler, turned friendly [01339591793]