1n73r.net

Television resolution and the human eye

Audioholics had a interesting article about 1080p resolution and how the human eye can/can’t see that well.  There were some really interesting points on how human eye site is measured and what that means for television resolution.  A few points I got out of the article were:

• 20/20 vision means that you can read the eye chart (Snellen chart) from the same distance as average people, but 20/10 means you can read from 20 feet what the average person has to be 10 feet to read.
• A movie theater screen subtends a viewing angle of 30 degrees or more.
• The resolution of our eyes is 12 vertical lines per arc angle (one line per arcminute for 20/20 acuity) times 2.
• You can find the degree of your field of view your TV fills your eye’s by using the formula tangent x (half the subtended angle) = opposite side length (1/2 TV’s horizontal width in feet) ÷ adjacent length (distance you are from the TV) and multiplied by 2 (because your TV is twice as wide as the length we used).
• You can then find the resolution you can see by taking the degree of view x 2 x 12 (or whatever vertical lines your eyes can see).  This number will give you how many pixels you can see from the distance you are sitting (in the example it was 672).  This means that if they had a 720p 50″ TV and they sat 8′ away they still would not be able to see 1 pixel let alone if they had a 1080p TV.
• The source of the video is still what matters most in your viewing pleasure.

I found it very interesting and is a great argument against upgrading just for the sake of having a 1080p television.

xlink kai

This is yet another post for myself to be able to replicate this setup at another time.

The background to this is that I used to always use xbox connect to play halo 1 online. It is a great system made by a great guy (woot Todd!). I was involved with the community for a really long time but recently I switched over to the dark side (xlink kai) because of their support for multiple operating systems and their connectivity with modded xbox’s. I was setting up xlink on my mythtv box (which actually seems to be working mostly) and I just wanted to post instructions on how to get it to work if I ever have to reformat.

Basically just download the tar.bz file from www.teamxlink.com and extract the file. Open kaid.conf with a text editor and adjust settings as needed. Once the settings are all done copy the kaid.conf file to the /etc folder and then the kaid file to /usr/bin. Now to run the xlink server simply type “sudo kaid” in a terminal. (or set it to run at start up).

Connecting from xbox media center is easy. Just go to the settings and then “My Programs”. Turn on the service and put in your user name and login information. After that everything in controlled from the xbox. It is a great system and I now can play halo 1 online without ever needing to touch a controller.

I hope this helps.

I haven’t had a chance to go through this script but I also saw this in the forums for running kai via a startup script. Enjoy.

How to Bypass BIOS passwords

I wanted to post this for my own future reference and also if it helps anyone else in the future.  I have been locked out of the bios with computers that have been given to me and also ones I have bought in the past and there is nothing more annoying than taking out the cmos battery and then finding out that the password doesn’t erase.  OK so maybe there are a couple of things that are more annoying.  But this is still frustrating.
Backdoor Passwords

Many BIOS manufacturers have provided backdoor passwords that can be used to access the BIOS setup in the event you have lost your password. These passwords are case sensitive, so you may wish to try a variety of combinations.

WARNING: Some BIOS configurations will lock you out of the system completely if you type in an incorrect password more than 3 times. Read your manufacturers documentation for the BIOS setting before you begin typing in passwords.

Award BIOS backdoor passwords:

AMI BIOS Backdoor Passwords:

Phoenix BIOS Backdoor Passwords:

Misc. Common Passwords

Other BIOS Passwords by Manufacturer

Toshiba BIOS

Most Toshiba laptops and some desktop systems will bypass the BIOS password if the left shift key is held down during boot

IBM Aptiva BIOS

Press both mouse buttons repeatedly during the boot

Using the Motherboard “Clear CMOS” Jumper or Dipswitch settings

Many motherboards feature a set of jumpers or dipswitches that will clear the CMOS and wipe all of the custom settings including BIOS passwords. The locations of these jumpers / dipswitches will vary depending on the motherboard manufacturer and ideally you should always refer to the motherboard or computer manufacturers documentation. If the documentation is unavailable, the jumpers/dipswitches can sometimes be found along the edge of the motherboard, next to the CMOS battery, or near the processor. Some manufacturers may label the jumper / dipswitch CLEAR – CLEAR CMOS – CLR – CLRPWD – PASSWD – PASSWORD – PWD. On laptop computers, the dipswitches are usually found under the keyboard or within a compartment at the bottom of the laptop.

Please remember to unplug your PC and use a grounding strip before reaching into your PC and touching the motherboard. Once you locate and rest the jumper switches, turn the computer on and check if the password has been cleared. If it has, turn the computer off and return the jumpers or dipswitches to its original position.

Removing the CMOS Battery

The CMOS settings on most systems are buffered by a small battery that is attached to the motherboard. (It looks like a small watch battery). If you unplug the PC and remove the battery for 10-15 minutes, the CMOS may reset itself and the password should be blank. (Along with any other machine specific settings, so be sure you are familiar with manually reconfiguring the BIOS settings before you do this.) Some manufacturers backup the power to the CMOS chipset by using a capacitor, so if your first attempt fails, leave the battery out (with the system unplugged) for at least 24 hours. Some batteries are actually soldered onto the motherboard making this task more difficult. Unsoldering the battery incorrectly may damage your motherboard and other components, so please don’t attempt this if you are inexperienced. Another option may be to remove the CMOS chip from the motherboard for a period of time.

Note: Removing the battery to reset the CMOS will not work for all PC’s, and almost all of the newer laptops store their BIOS passwords in a manner which does not require continuous power, so removing the CMOS battery may not work at all. IBM Thinkpad laptops lock the hard drive as well as the BIOS when the supervisor password is set. If you reset the BIOS password, but cannot reset the hard drive password, you may not be able to access the drive and it will remain locked, even if you place it in a new laptop. IBM Thinkpads have special jumper switches on the motherboard, and these should be used to reset the system.

What is that internet connection.

Once again this is more for my reference than for anything else. But I came accross this from digg and thought I should post it on here in case the site ever disappears.

T1 or DS-1 – This is the equivalent of 24 phone lines.
It had handle 1.5 million bits per second [1.5Mbps]
The key word is BITS not bytes. Bits are much smaller
then bytes – and they have a vary compare to a byte.
A bit is One – A byte can be 4,8,10,12,16 depending on
the thing we are talking about – The telecommuncations
industry uses bits – so we do to.. Please never confuse
the two. From a PC standpoint 8 bits equal one byte.

T2 or DS-2 – This is the equivalent of 4 T1′s. The capacity is 6.3
million bits per second [6.3Mbps]

T3 or DS-3 – This is the equivalent of 28 T1′s. The capacity is 45
million bits per second [45Mbps]

T4 or DS-4 – This is the equivalnet of 6 T3′s. The capacity is 274
million bits per second [274Mbps]. Sprint currently
uses DS-4 for the backbone.

OC-1 – Sometimes called SONET. OC-1 uses ATM switches [as
all OC-X does] and runs at 51 million bits per second
[51Mbps]. Uses Fiber

OC-3 – This is the equivalent of 155 million bits per second
[155Mbps]. MCI currently runs a few of these on their
backbone.

OC-12 – 600 million bits per second [600 Mbps]

OC-48 – 2.4 gigabits per second [2.4 Gbps]

Frame Relay – Basically dead and gone as far the Internet is concerned.
Especially with the bandwidth requirements the way they are.
Frame relay runs around 64kbps to 1.5Mbps [64,000 bits per
second to 1.5 million bits per second]. Frame Relay is
shared line with other people and your bandwidth depends
on the current utilization of the line.

ATM – Asynchronus Transfer Mode. ATM is a very expensive switching
solution that is used in carry OC-3 and OC-12 lines.