Tech Notes has a good 63 page PDF answering the common questions about the DTV Transition coming up in the US. Tech-Note – 141. Dec 17, 2008. It says it was written for the broadcast engineer and technician who will be dealing with the transition first hand. That means it answers some questions you don’t often find elsewhere. It does not get technical and is easy to read evwn if you are not an engineer or technician. There are also many good links to websites that can provide additional information.
Archive for December, 2008
DTV Transition FAQ
Sunday, December 21st, 2008Remastering an installation system
Sunday, December 21st, 2008A backup is best considered as being in two parts. One is your system and the other is your data. A system backup needs to be in the form of a bootable media that can re-install your system with all of its settings and applications. Remastersys is a utility that does this and looking at how it works can help better understand what it takes to make a bootable media. Here are some of the Linux utilities used by Remastersys for a system backup and some of the documentation available to understand what these utilities do.
SYSLINUX – The Easy-to-use Linux Bootloader – this is the connection between the machine BIOS boot software and the Linux Kernel
SQUASHFS – A squashed read-only filesystem for Linux
- this is a means to store all of your system in a compressed form so it takes up less room on the backup media.
UnionFS – Wikipedia, the free encyclopedia
- this is the means to allow writing to a read only file system. It does this by writing to somewhere writable and then merging that with the read only file system.
Introducing initramfs, a new model for initial RAM disks
- this is the media built into the kernal used to hold the programs and instructions needed to mount the hardware used by the system and get the system set up and ready to go.
Ubuntu — ubiquity-casper
- this is the system installation utility for Ubuntu.
LiveCDCustomizationFromScratch – Community Ubuntu Documentation
- a description of the process used to build a live CD
Jesse Caulfield » Unwrapping the Ubuntu Live CD
- a step by step guide to taking apart a live CD so you can see what is in it and how it is built.
How to create a custom Ubuntu distro – It’s My Life
- a walkthrough of the steps required.
How-to: Installing Ubuntu Linux on a usb pendrive | Debian/Ubuntu Tips & Tricks
- a tutorial
Linux.com :: Discover the possibilities of the /proc folder
- Finding out about the processes on your system and using that to learn about what is going on with your system
Creating Custom Ubuntu Live-CD With Remastersys — Ubuntu Geek
- Here’s how to install and use this utility that will make media images of your system easy.
5 Free Linux Backup Solutions
- for the other half, the data half, of your backup.
Tectonic » Clone Linux, Windows disks with Clonezilla
- this creates an image copy of your existing media. It is another form of backup from the file based backup that the other methods discussed here use.
Novell SUSE and a bit of history
Sunday, December 21st, 2008SUSE against the tide, 19 December 2008 by Richard Hillesley at Tux Deluxe
SuSE was founded in Nuremberg, Germany in 1992 … The capital moment for SuSE had passed. But three years later everything changed. Novell, the network company of the 80s, jumped in and bought the company, assisted by a loan from IBM…. YaST, the SUSE installer, was released under a free software license. SUSE Linux was made available in three different forms, openSUSE, a freely downloadable bleeding edge community distribution (which was a first for SUSE), SLES (SUSE Linux Enterprise Server) and SLED (SUSE Linux Enterprise Server).
This is another flavor of the commercial/open business model for linux distributions following Red Hat and Fedora, Canonical and Ubuntu, and perhaps even IBM with its Lotus suite. Where it gets interesting is in Novell’s license agreements with Microsoft and the legal tussles with SCO.
The audio pipe
Wednesday, December 17th, 2008What kind of audio connection do you have in your AV system? It will determine what you can get out of your audio experience.
There are three ways of hooking up your PS3 for audio: using RCA cables (red and white), using optical out, and using HDMI. I guess you could consider using a RF cable as a fourth choice, …
RCA cables only allow for Dolby Pro Logic, … It “simulates” having surround sound without actually providing true tracks for each speaker. …
Optical out can carry DD5.1 and DTS tracks to your receiver, providing a much clearer, enjoyable sound. I highly recommend using optical cable, as the results are VERY noticeable. Optical only has enough bandwidth for PCM 2.0 uncompressed, resulting in uncompressed stereo sound (stereo? Meh!). To get the full PCM 7.1 experience, you’ll need…
HDMI. This can carry the next gen audio formats such as DTS-HD MA, Dolby True-HD and uncompressed PCM 5.1-7.1 audio at a full bitrate. The only other method of getting these codecs is through analog out, which is not supported by any console on the market today (but is supported by stand alone HD-DVD and Blu-Ray players). [HOW TO: Get uncompressed PCM 5.1/7.1 audio from your PS3!]
The issues involve the basic fidelity of the recording, signal compression, signal packaging, and the number of channels. The fidelity in modern audio is a digital measure of both how many bits per sample and the frequency of sampling. Signal compression is used to minimize storage space and connection bandwidth.
The latest and greatest audio is 7.1 or 8 channel audio where one is an LFE or low frequency effects channel that doesn’t have the fidelity requirements of the other 7. The latest HDMI standard: “supports 8-channel, 192kHz, uncompressed digital audio and all currently-available compressed formats (such as Dolby Digital and DTS), HDMI 1.3 adds additional support for new lossless digital audio formats Dolby® TrueHD and DTS-HD Master Audio™ with bandwidth to spare to accommodate future enhancements and requirements.” [HDMI FAQ]. This is the latest HD resource such as is available on some Blue-Ray recordings.
The previous generation, standard DVD, used 5.1 audio in a compressed form that used S/PDIF connections (see Wikipedia).
Before that was the 2 channel stereo connection that uses techniques like Dolby Pro Logic to get surround sound.
The acceptance of MP3 audio players and the near equal quality of Dolby and DTS on DVD presentations indicates that 5.1 channel compressed audio is near the knee of the curve and improvements such as the 7.1 uncompressed extra depth audio are down in the noise of equipment choice and environment for most folks.
See also Swedish Radio What is multichannel sound and how does it work? – see the multichannel check for samples to test your system. -|- Spanner Works Dolby Digital, DTS and DVD: A History -|- Practical Home Dolby vs DTS – Which is Better? for more information about the history, the techniques, and what it is all about.
ASCII – cognitive disconnect
Thursday, December 11th, 2008One of the biggest hassles with understanding things technical is making the right mental connections. Text Files Are Mysterious describes a system administrator’s difficulty in this area. He is asking for a log file from a user to be able to diagnose a problem.
Moral of this story is: regular users do not understand plain text. I should keep it in mind when I teach my class and talk about ASCII code. When I say “plain text” some students probably thing “word doc with no formatting”. Lesson learned.
Also, if you didn’t get this, I am not going to explain it.
You’d think, with the popularity of text messaging on cell phones, that the idea of plain ASCII text was better understood. But then, file formats as a general concept seems to be rather difficult to learn.
One of the ‘features’ of Unix type systems is that they are heavily text based. Configuration files and source code are both easily viewable and editable with simple text editing tools. Even the more modern web pages and document file formats are plain text with formatting and meta-data coding that can be deciphered by simple text viewing.
The first step to really being in control is to have a good basic model for how it works. The barriers to gaining that understanding are most often in your approach and not the technology.
Is TV the right place to put your money?
Wednesday, December 10th, 2008John C. Dvorak has a point with his essay It’s the TV Killing the Computer, Not Vice Versa. TV’s are the big ticket items at places like Costco but PC’s can be had for about the same price – and many of us spend more time with the PC than the TV. Then there is point about what you look at on the screen.
TV is designed for small screens. Through trial and error over the decades, the camera angles, shot selections, framing, and everything else about a TV show have evolved to maximize the impact on a 21-inch view space. This is not a lot of real estate. And blowing it up to a 42-to-60-inch image in a 16-by-9 widescreen format often ruins the impact.
There is change in the wind, though. The producers are beginning to find out what you can do with widescreen aspect ratios and HD. The audio part should also not be ignored as the trend is towards surround sound with significant detail there as well. The CSI shows are good examples of the experiments with high definition digital presentations.
In other words, it is not just the technology but how it is used.
Updates – pain or indicator of active life?
Tuesday, December 9th, 2008The updating business is a pain in the neck. I have to boot to Vista every couple of weeks to keep up to date and, sure enough, there is another 20 or 30 MB of updates to download and install. Most of the times, it seems, these are important enough to require a reboot to finish proper installation.
Linux isn’t much different. This morning was an OOo update as it needed 65 MB and was complaining about broken packages and needing to remove things. We’ll see if I still have a bootable system when it gets done.
Then there are the web service applications like WordPress. DreamHost does facilitate installing and upgrading its selection of the most common FOSS web server applications but it still requires going to their administration page and choosing the upgrade option. Then you have to go reset any customizations you may have done for the previous version.
These updates and upgrades not only fix things, they ‘improve’ things. That means you get some surprises, some good and some not so good, when you update your system.
It is a pain as it is something you need to do but it is also an indication that there is active development and support behind your software and that has to be a good thing, ya’ think?
USB Drive mount problems Ubuntu 8.10 Intrepid
Monday, December 8th, 2008It seems that the Ubuntu upgrade has done something to the USB drive detection. DMESG shows a continuous loop when a Buslink 40 GB USB 2.0 drive is attached.
[15183.419492] sd 9:0:0:0: [sdf] Add. Sense: No additional sense information
[15183.421486] sd 9:0:0:0: [sdf] Sense Key : No Sense [current]
This appears to be a known kernel bug (287701 or 262344 or 273372) The discussion at launchpad about bug 264789 is a good example of how people try to find a fix for this sort of thing. That discussion lead to bug 221983 which suggested a udev rule fix.
The comment by Grzegorz Ślusarek to add ENV{DEVTYPE}==”partition”, at the front of line 59 did fix this particular problem. That invites some investigation into UDEV rules to figure out what this change actually does. Tim Wright notes that “It fixes the issue for me too. The problem is, it probably breaks hotplug access to filesystems on unpartitioned devices.”
Also note that messing with these files is a temporary fix. An update or upgrade to the UDEV software may well overwrite these changes.
Also keep in mind that invoking root privilege to make changes in configuration files for basic services, like hardware access, is like taking off cross country in unknown territory. Be prepared for the worst.
kpatience
Sunday, December 7th, 2008An upgrade to the solitaire game provided a new look and feel. Kpatience 3.0 on KDE 4.1.3 The autodrop is slowed down. There is an indicator to tell you whether or not the game can be won at your current point. Game -> Statistics will give you the rundown on how many games you’ve played and your winning odds.
The game status can be an interesting item when coupled with the ^z back up a move. You can find certain innocuous plays that change the status from winnable to not winnable, back up and go a different direction. Often it is a card in the stack that would be blocked. Figuring out what can be interesting.
Too much time playing solitaire on your computer is an indication you need a faster computer or network connection, right? I mean, the only reason to use such applications is to keep busy waiting for the document to come up or some such?
UPDATE: The new version doesn’t seem to do that annoying ‘knotify’
thing when you win; a long stack going down to the bottom of the display window will shrink if you add cards that would otherwise take the stack off the bottom – more nifty animation.
WordPress: backup
Sunday, December 7th, 2008Having a means to back up things is good. Testing them to make sure they work is better.
Been there, done that. WordPress has import and export functions and they seem to work.
I exported the Whispers entries and save the file in my local file system www backup folder. Then I imported that file to this blog. All there!
The hassle is then going to manage posts, filter by a whispers category, and select all of each page to delete the posts in the categories that belong there and not here. Then clean up the categories.
The result is that the posts about eBox and codecs and such stuff that belongs here is now copied here.
Content re-arranging and resturcturing is a part of growth. A good backup system can facilitate this effort as well as provide a backstop if something goes awry. It looks like the WordPress export and import functions can provide an adequate service for these needs.