Categories
code electronics work

Simple ATTiny85 USB board

IMG_20140623_121908_fixI needed to create a small, cheap USB-enabled circuit to serve as a key logger, and I’ve found some nice projects online that explain how to do this.
I found out you could use an ATTiny85 to run the V-USB software USB stack, and I only needed the one input pin to gather data (it’s going to be a USB “That was easy” button).
Since this was done so many times before, I will be brief, and try to point out problems I had instead of a regular tutorial.

Categories
linux Solutions

Struggles with creating Linux Live USB on Mac OSX

SO I’ve been trying to create a bootable live USB of some linux distro on the Mac and failed consistently. That is – until I found a magical solution!

Categories
code programming python school tips

GDoc/LaTeX compilation GUI with Tkinter/Python [w/ code]

¡Hola mis amigos!
I’m learning spanish, but I’m also annoyed with collaborating on LaTeX papers. That’s why I’ve created the GDoc-LaTeXifier so the syntax will be clear when I collaborate on a paper with a remote friend.
But now we both want to compile a PDF on our machines. So I’ve created the tiny shell script that downloads the paper and runs PDFLaTeX.
The problem is that this opens a new terminal window and runs the script. I’ve been able to sort it out so that it closes the terminal window when it’s done, by on my friend’s mac it doesn’t, so he ends up with a ton of open windows.
Enter – the GDoc/LaTeX compiler GUI.

Categories
linux Raspberry Pi Windows

Share NFS from Windows

I recently bought a second raspberry pi, for the purpose of making it a “dumb” media center running XBMC (Raspbmc to be exact). I already have a media center PC running XBMC on Windows 7, and I wanted to connect my raspberry pi to the downloaded media, stored remotely on the Win7.
First, of course, I tried SMB (windows share). It worked… ok. But after installing a new HP Wireless printer, it seemed to disconnect a lot. I don’t fully understand why, but it appears that the printer publishes itself as SMB master thus disconnecting my other SMB connections (or maybe only Linux ones)
Anyways, I have spent almost two days, understanding how to connect the Raspberry pi to Windows 7 using NFS. It was not easy, because it seems Microsoft has dropped support for it on home OS (even Win7 ultimate) since Windows XP.
I ended up doing it with Cygwin (which gives powerful Linux capabilities to windows machines).
I want to outline what I have done in order for this to work. This process could be very easy and it could be frustrating. I really hope it will help you do it yourself.
So it might do the trick as step-by-step, and you might come some obstacles on the way
The original guide I used can be found in this link, however it did not work at once and I had to tweak a bit. Also, it is referring to Windows XP.
As this is not step-by-step in full, with screenshots, it might help you on your journey. This can also help you with any windows share to be exported to linux
Here it is:

Categories
Music Uncategorized

Trying out my mashup skills

This is not proper technical thingy, but I took some time to try out some audio skills by doing somewhat obvious mashup
Came out pretty good, in my opinion
Sara Baraeilles’s “Brave” and Katy Perry’s “Roar” sound very similar. So I took two acapellas and instrumental and mixed them together.
Enjoy (or.. not)
[soundcloud url=”https://api.soundcloud.com/tracks/127472720″ params=”color=ff6600&auto_play=false&show_artwork=true” width=”100%” height=”166″ iframe=”true” /]

Categories
Uncategorized

Speak friend and enter

Screen Shot 2013-12-21 at 12.58.00 PM

Categories
code graphics opencv programming

Simple NURBS renderer [w/ code]

Screen Shot 2013-12-18 at 11.01.23 AMDon’t you just love scouring the web for a piece of simple code, come up short and then just write it yourself? Well that was the case with NURBS for me. These simple curvy lines, why doesn’t anyone just dish out a straightforward implementation of them? Well, now you have it. I wrote a simple renderer that reads a DXF file with NURBS (from Rhino3D) using DXFLIB, although the DXF file format is super easy to parse, and renders them to an image with OpenCV.

Categories
code programming

Simple HID driver to save an old AIPTEK HyperPen tablet trashing

rect3948So I have this incredibly old and stupidly cheap AIPTEK tablet (like a Wacom, only Chinese and cheap) that is so outdated it practically has almost no existence online. Why did I bring this item across the atlantic? I have no answer, but it’s here anyways and I can’t seem to bring myself to trash it. Of course no drivers are available for it so I wrote a tiny simple driver using the great libHID library from Brandon Fosdick. It was painless, and my old tablet was saved.

Categories
code tips

LaTeX colorization in Google Docs with AppScript [w/code]

Screen Shot 2013-12-03 at 7.38.53 PMThere’s a fantastic way to collaborate when writing an academic paper in LaTeX – using Google Docs. LaTeX is all text anyway, so collaborating over GDocs is straightforward, but alas there is no colorization to make it like a good LaTeX editor… Fortunately there’s AppScript to help us!

Categories
code

Creating a searchable PDF with opensource tools ghostscript, hocr2pdf and tesseract-ocr

I bet creating searchable PDFs has been done many times over, even so I’d like to share the way I did it recently with strictly open source tools. The pipeline is simple: GS to separate the PDF to pages, tesseract OCR to extract text, hocr2pdf to create a merged PDF and GS again to bundle everything back to unified PDF. If you’re creating a PDF from scanned books, this project may also be of help: unpaper
Edit 5/21/2014: I’ve had good experience using Scantailor, which is available on homebrew for the Mac. And also, I’ve submitted hocr2pdf to homebrew as part of the exact-image library (the name of the formula is “exact-image”).