Thursday, April 30, 2015

Edit Your Photos!

I'm not a professional photographer. Nor do I claim to be an artist. But even I know a lousy photo when I see one -- and the internet is littered with them. Cropping and retouching is an easy way to greatly improve any photo. Here's an example:







The original photo is fine but has a few obvious flaws:
  • The statue looks far away. The details of the face on the aren't clearly visible.
  • It has a modern glass window and a pink sign in the background.
  • It's perfectly centered, which is generally wrong for portraits. See the Rule of Thirds

A tight crop -- using the Rule of Thirds -- removes the unwanted background, and draws your focus to the statues' eye. A little sharpnening exposes the stone's rough texture on the face and neck. Increasing the color saturation highlights the discoloration caused by years of weathering.

Total editing time: five minutes. Cost of software (gimp): zero.

Tuesday, December 16, 2014

Fused Glass Reindeer

Overview

This blog describes how to make a fused glass reindeer Christmas ornament.



Reindeer


Pattern

Materials

To make this design you will need the following glass:

  • Brown
  • Red
  • Green (Bulleye's Aventurine Green)
  • White
  • Clear

Also recommended is a 2" piece of high temperature wire.

Components



Antlers

Cut a strip of green glass as thin as possible (about 3/16" or 0.5cm):

Approximately 10" is need for one reindeer. Cut the strip into six pieces as follows:

  • Four pieces 2" long
  • Two pieces 1" long

Whites of the Eyes

Cut two 3/8" squares from white glass. Remove the corners and then grind them into rough circles.













Pupils

Wrap a scrap piece of black glass in paper and hit it with a hammer. Pick out two roughly round pieces about 1/8" in diameter.














Don't forget to wear eye protection and sweep up any stray piece.

Remaining Components

Cut the remaining components as specified in the pattern.
  • Cut the ears and face from brown glass. Becareful to preserve the bulges on the side of the face; without them the eyes will droop off of the reindeer's face.
  • Cut the clear semicircle. It must be smaller than the width of the face and the red nose.
  • Cut the nose out of the brightest red glass available.

Summary

Below is a picture of all the parts needed to make one reindeer:


Assembly





1. Place two-inch antler pieces




2. Place wire (optional)




3. Place one-inch antler pieces


  1. Place two-inch antler pieces in a V-shape.
  2. Place high temperature wire on point of antlers.
  3. Place one-inch antler pieces parallel to two-inch pieces such that there is a 1/2" gap between.




4. Place remaining antler pieces




5. Place ears




6. Place brown face piece


  1. Place remaining two-inch antler pieces vertically on top of the existing pieces.
  2. Place ears roughly horizontal, nearly touching in the middle.
  3. Place the brown face piece such that the top covers the ends of the antlers and ears, and the bottom rests on the kiln shelf.




7. Place clear semicirlce




8. Place nose




9. Place eyes


  1. Place the clear semicircle below the face.
  2. Place red nose piece such that it overlaps the clear semicircle by about 1/8".
  3. Place eyes and pupils.


Fusing

Place the reindeer into the kiln, and fuse at 1465oF for 3 minutes. Anneal for 20 minutes at 960oF. Flash cooling (crashing the kiln) is not necessary.

Finished Reindeer


Tuesday, February 24, 2009

Project Deanvo

Introduction

Several years ago I decided to discard my Tivo, and replace it with a Linux-based digital video recorder (DVR) built from off-the-shelf computer parts. My friends at work dubbed this Project Deanvo.

Digital Video Recorder Overview

A Digital Video Recorder (DVR) is a computer with the ability to record, and play video. Typically these devices have a controlling piece of software which schedules recordings, and automatically changes the channel on your cable TV box, or satellite dish.

Other than the basics, many DVRs have the ability to play DVDs, create DVDs, capture streaming Internet radio, download podcasts, listen to MP3s, view photos, and just about anything else possible on a general purpose computer.

Why Build a DVR?

The short answer is no sane person would build their own DVR. It's expensive, requires significant time and effort, and the most commonly used software (MythTV) is far from perfect.

But Tivo has begun to engage in some questionable business practices:
  • Tivo monitors the programs you watch. Of course, they claim this information is not used for nefarious purposes.

  • Tivo automatically downloads advertisements. This is particularly galling since you're paying for it. The whole point of a Tivo is to avoid ads.

  • Tivo makes it difficult to cancel your subscription. You can sign up online, but canceling requires a lengthly phone call. They put you on hold forever, and then you have to listen to their retention sales pitch.
A Tivo also require an expensive monthly service ($13/month). And Tivo controls your recordings; there's no easy way to extract them. In short, a homemade DVR allows you to regain control of your TV.

Quiet and Green Components

The hardware requirements of a DVR are slightly different from a general purpose computer. DVRs are usually never turned off, so a green (low power) machine is desirable. Also, a quiet DVR is essential, as any noise might disturb playback. But the machine must have enough processing power to play high bit rate video. And a powerful CPU typically requires a noisy fan. Fortunately there are a number of green, and quiet options available. Here's the part I used:
Antec NSK2400 Case


The NSK2400 is specifically designed to be a media center PC. It has two 120mm fans which provides good ventilation with minimal noise.


AMD64 3800+ CPU


The AMD64 3800+ draws only 45W, and can programmatically have its clock rate lowered to save even more power. Still, it has enough processing power to easily play DVD quality video.


Rosewill RCX-Z2-EX Heatsink


The XP-90 has four heatpipes bonded to aluminum fins. It is designed to dissipate 125W of heat -- about 3 times what the AMD64 3800 generates. This allows CPU to run with the fan off most of the time.


Corsair VX450W Power Supply


The VX450 is very quiet, and its efficiency rating is 80 Plus.


Western Digital WD10EACS 1TB Hard Drive


The WD10EACS is a high capacity (1TB), low noise, energy efficient hard drive. Perfect for a DVR.


Hauppauge PVR-250 Video Capture Card


The PVR-250 is a common component for a home made PVR. It has a hardware MPEG2 encoding engine which produces DVD quality video.

LCD Display

Some DVRs have a front panel display. While not absolutely necessary, it adds a nice finishing touch. I bought an LCD display from All Electronics, and built some control circuitry, and a carrier:

LCD Carrier

LCD Circuit Board

Cover


Here's what it looks like assembled:

LCD Display Assembled

LCD Display Installed

Satellite Dish Control

A DVR must be able to change channels on a cable, or satellite dish box. This is accomplish this by mimicking the infrared codes sent by the remote control. Commercial infrared transmitters typically do not support Linux.

After some research I decided to built my own. The circuit is remarkably simple:

Infrared Transmitter

Circuit Diagram


The Max232 provides a serial connection to the computer. The PIC microcontroller is a one-chip computer. It is loaded with the following microcode:
ir.asm

Software (MythTV)

The de facto standard for a Linux-based DVR is MythTV. It is far from perfect, but it does have many attractive features:
  • Commercial flagging. Tivo lets you fast forward past advertisements, but MythTV allows you to skip the entire commercial break with the press of one button.

  • Distributed playback. MythTV is divided into a recording module (backend), and playback module (frontend). This provides an built-in Slingbox-like feature enabling playback on any Internet-connected computer (PC, Mac, Linux). And since MythTV supports Universal Plug and Play (UPnP), it also plays back on Sony's Playstation 3 and the Samsung 8-series LCD TVs.

  • Inexpensive monthly service. MythTV needs a database of TV listings. While it is possible to extract (scrap) this information from web sites like TVGuide.com, almost all MythTV users buy a subscription from schedulesdirect.org. It's cheap ($20.00/year), and very reliable.

  • Open source development. The main advantages are that it's free, new feature are added rapidly, and bugs get fixed quickly.

  • Numerous Plug-in Features. MythTV is designed to be extended by a third party. For example, MythVideo can import, transcode, and play DVDs. MythWeb provides a web interface, which allows you to schedule a recording from any computer with a web browser.

Here's a few screen shots:

MythTV Main Screen

MythTV Recorded Programs



MythTV Program Guide

MythTV Program Playback

NPR Recorder

I listen to a lot of National Public Radio (NPR). It's the PBS of radio. Since most NPR stations have streaming MP3 broadcasts, it's pretty easy to automatically capture recordings. I cobbled together some perl scripts which are activated by a cron task, and voilà: NPR Tivo. Here's the relevant files:

npr_tivo.tar.Z

Conclusion

It was a lot of work, but I love my MythTV box. Of course, a year after I got everything working, I bought an HD TV. My MythTV box only supports 480i (DVD resolution),while the TV supports 1080p (full HD resolution). I suppose it's time to upgrade. That's the problem with computer technology: if it's working, it's out of date :)

Monday, February 23, 2009

Oscar Bingo

Fun Watching the Oscar

I went to an Academy Awards party, and everyone had a great time playing Oscar Bingo. Each card has 25 squares containing an Oscar category, and one of the two top nominees. The first to get five in a row wins.

This web page generates a random Oscar Bingo card:
Oscar Bingo Page

Each card has about 30% chance of a bingo, and we wanted a winner so the three of us each played two cards.

Results

Below are my two bingo cards. I got knocked out early.
Dean #1

Dean #2

Midway through the cerimonies Dave got four in a row, needing only Best Picture / Slumdog Millionare for bingo. Nate Silver estimated Sumdog's odds at a whopping 99% -- a virtual lock! But Best Picture is announced last, so if somebody else could beat him to the punch ...
Dave #1

Dave #2

Late in the ceremonies, Rich needed Best Actor/Sean Penn, or Best Actress/Meryl Streep -- both considered long shots. But Penn pulled off the upset sending Rich to victory.
Rich #1
Rich #2

Unbingo

The best part of the game is speculating about possible paths to victory, trash talking, and whinning about our bad luck. We soon realized that five loosing squares in a row (unbingo) was almost as difficult. So next year the first to unbingo will get a VHS tape of Plan 9 From Outerspace.

Sunday, February 1, 2009

Dog of a Thousand Faces

FOPAL

I recently started volunteering at the Friends of Palo Alto Libraries (FOPAL). This nonprofit organization receives donations of books, and sells them, with the proceeds going to the local libraries.

One of the stranger traditions at FOPAL is the dressing up the stuffed animal mascot named Le Woofer. FOPAL sells books once a month, and Woofie, and his wicker bird companion are dressed to match a major holiday in the month. e.g. For December Woofie was Santa Claus. It started when somebody donated Woofie to FOPAL, and since he was clearly not a book nobody knew what to do with him. The volunteers started propping him up in the "Earth and Animals" section, or hunched over a keyboard. And then it got out of hand. None of this makes any sense, but traditions rarely do.

Woofie the Clown

In October Woofie is dressed as a clown for Halloween. The base outfit is a children's costume. The nose is a Christmas ornament. The hair is polyester fiberfill, and some fluorescent paint.

Woofie Claus

In December Woofie is Santa Claus, and the bird a reindeer (note the blinking LED nose). The chimney is a couple of moving boxes glued together and painted red.

Woofie the Drunk

In January, it appeared Woofie has had a bit too much to drink at a New Years Eve party. The foam coming out of the bottle is a product called Great Stuff; it's spray insulation in a can. Inside Woofie's hat is an mp3 player which added a snoring sound effect.

Woofie in Love

February is Valentine's Day, and it looks like Woofie has a case of puppy love. The heart has 16 LEDs controlled by a programmable chip called a PIC. Sound effects are supplied by a small digital voice recorder. The big red button activates the everything.



Here's a short video of Woofie in action:

woofie_puppy_love.avi (15MB)