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Dewey Color System

These are the color names and interpretations used in the Dewey Color System.

SmartMedia Card Reader UIS4S / UIS5S / UIM4S / UIM5S

I got this SmartMedia reader from supermediastore.com, and I use it with a Fuji digital camera. I am running MacOS X on a flat-panel iMac.

I noticed that my Smartmedia cards did not always show up on the desktop when I put them into the reader. Sometimes they would show up after a long wait (over 2 minutes). The original 16M card that came with the camera never mounted with the reader — I only ever got it to mount by putting it in the camera and connecting the camera via its USB cable. The 64M and 128M cards sometimes mounted and sometimes did not. Then if I pulled the card out, I got an error message from the Mac ("There are no formatted volumes on this media, do you want to continue, erase or eject?").

I was able to eliminate all the problems by formatting the cards in the camera. The camera has a "format" command in the same menu as the "erase frame" and "erase all frames" commands. This command places a new, blank MS-DOS format volume on the card. After formatting all the cards this way, they all mount quickly and reliably, even the 16M card.

Multiple negatives annoy me. Why can't they write it more simply?

CNN Headline News, "In response [to the terrorism threat alert level] the FCC has rescinded the waivers on flyover bans at sporting events"

"I forgot to remember to forget" (a track on the Beatles Live at BBC disc 2)

Psychological primary and secondary colors for HTML

F60 Orange F00 Red 90F Purple 00C Blue 0CF Cyan 090 Green 9F0 Chartreuse FF0 Yellow

Two different versions of a children's "campfire song" with senseless lyrics. I would like to learn the origin of the lyrics. I suspect they used to mean something, perhaps in a different language.

Flee
Flee
Flee Fly
Flee Fly
Flee Fly Foe
Flee Fly Foe
Veesta
Veesta
Qumalama Qumalama Qumalama veesta
Qumalama qumalama qumalama veesta
hey, no no no no no laveesta
hey, no no no no no laveesta
eeniemeenie exameenie oh, ohmaneenie
eeniemeenie exameenie oh, ohmaneenie
Big baddy oh, scaboe, scawinda
Big baddy oh, scaboe, scawinda!

Where does the MacOS Finder store the data for burning a CD-R or DVD-R?

This has been a mystery to many people using MacOS X, concerned with making sure the disk space is freed when the burn operation is complete, particularly when there is a power failure or crash in the middle of the operation. The MacOS Finder lets you create a "disk" on the desktop which will become your CD-R (or DVD-R), copy files to it, move the files around, rename or delete them, etc. before finally telling it to burn the disc.

Typically, this is done by using a hidden file somewhere on the hard disk which holds a disk image or volume image of a filesystem which is then burned to the disc. After burning, the image file can be deleted. But if you reboot before burning, the image file might be left around.

Another possibility is to use memory: keep the disk image in memory, and rely on the virtual memory (VM) system to store the data in swapfiles on an as-needed basis. This has an obvious advantage: in the event of a crash or if the Finder unexpectedly quits, the storage is reclaimed by the kernel's VM system, so there is no need to worry about reclaiming the space. A major disadvantage is that it would take 4.7 GB of virtual memory to burn a DVD. Since MacOS (prior to version 10.3) is limited to 4 GB of memory, this is clearly not how the Finder does it.

Virtual memory on MacOS X is handled through the Mach kernel, using an on-demand paged swapfile system, with swapfiles on the root filesystem, not in a dedicated partition. Swapfiles are 80 megabytes (80000000 bytes) in size and are stored in the /private/var/vm directory with names like "swapfile0", "swapfile1", etc.

Swapfiles exist only for the extra swap space needed on top of the physical RAM. For example, on my system I have 384 mebibytes of RAM, and after rebooting there is a single "swapfile0" file in /private/var/vm. After launching a lot of applications, with a lot of open windows, etc. more swapfiles are created. At any time, you can see how much space is being used for swapfiles by using the shell command:

du -sk /private/var/vm

(note, this will probably print a message like "du: /private/var/vm/app_profile: Permission denied" This message is harmless and can be ignored.)

Scans of the filesystem during a Finder CD-ROM burn seem to show that the data is kept in a directory inside the "Volumes" folder on the boot volume. However, like all directories in /Volumes, this directory is also mounted on a driver device (use the mount command to see this). FireWire and USB drives, mounted disk images, CD-ROMs, remote network volumes and so on all appear here, and their size does not count against the size of the hard disk.

Circus Peanuts

These candies more than any other type of food I have encountered, seem designed to produce synesthesia in the eater: They are peanuts in appearance, but are made of marshmallow, taste like banana, but are colored orange. Given their long history, going back to the late 19th century, it seems likely the creator of the Circus peanut was using a hallucinogenic.

Origin of "29.97" frame rate in the NTSC television standard

The first NTSC standard was black and white only, and was precisely 525 lines with precisely 30 frames per second: 525 × 30 = 15730 lines per second. The audio was sent as a high-frequency subcarrier, a 4.5 MHz signal added to the video signal. If the raw signal were viewed on a CRT with sufficiently good focus, the audio would be visible as a series of dots spaced at a distance of about 285 dots per line (that's 4.5 million divided by 15750). But the dots move from one frame to the next, and usually the signal would be filtered properly so they are not seen.

When color was added to the NTSC standard, the primary objective was to make the new color signal viewable on old B&W sets. This meant they had to stay very close to the frame rate of 30 frames per second, and 525 lines per frame, and the audio subcarrier had to remain at close to the original 4.5 MHz.

The only practical ways to do this are to add another subcarrier — either at a higher frequency or at a lower frequency than the existing audio subcarrier. Adding it at a higher frequency would make the TV signal take up more bandwidth — and this was not possible — neighboring TV channels, like channel 8 and channel 9, would interfere with each other. So they had to use a lower subcarrier.

But if the color subcarrier was lower, it would be visible in the picture on a B&W set. For example, if the color subcarrier was 3.5 MHz, you would see a pattern of bright and dark spots on each scanline, with about 222 dots per line (3.5 million divided by 15750).

To avoid having this pattern of dots be visible on black and white sets, the color subcarrier frequency was chosen very carefully. RCA engineers discovered that the pattern would be nearly impossible for the human eye to notice if the color subcarrier frequency is an odd multiple of one-half the horizontal scan rate. This creates a pattern of dots that alternates like a checkerboard from one scanline to the next, and where each dot alternates from white to black to white again from one frame to the next. Other engineers had determined that the optimum color subcarrier frequency was around 3.6 MHz, with a 600KHz bandwidth. Ultimately they picked 455 as their "odd multiple". If the frame rate were kept at 30 frames per second, the color subcarrier would then be 455 / 2 × 15750 = 3.583125 MHz.

One problem remained: the color subcarrier also interferes with the audio subcarrier, in a way that causes visible patterns to appear on B&W sets when there is both a lot of sound and a lot of color at the same time. To fix this, the color NTSC specification also adjusted the frame rate a tiny bit, so as to cause the difference between the audio subcarrier rate and the color subcarrier rate to be an odd multiple of one-half the horizontal scan rate. This was achieved by slowing the frame rate to 29.97002997. This caused the horizontal scan rate to be 29.97002997 × 525 = 15734.26573425, and the color subcarrier to be 455 / 2 × 15734.26573425 = 3579545.4545. The audio subcarrier is still exactly 4.5 MHz, and the difference between the audio and color subcarriers is 920454.5454 KHz, which is 117 / 2 times the horizontal scan rate. The new, slightly slower frame rate was still close enough to the original that the existing B&W TV sets would have no trouble displaying the picture.

The color NTSC spec defines the color subcarrier frequency to be 3579545 Hz plus or minus 10. The frame rate is defined from this. With the +- 10 Hz variation, the frame rate can be anywhere from 3579535 / (525 × 455 / 2) up to 3579555 / (525 × 455 / 2), or 29.96994 to 29.97011, with 29.97003 being the middle of the range.

See also my pages about digital video codecs and film formats.

Partial test of New York Times article reporting the first performance of the dance troupe Pilobilus.

Dance: New Group From

Four in Pilobolus Show Athletic Skill

By ANNA KISSELGOFF

Pilobolus, a dance group formed by four Dartmouth men as an outgrowth of dance classes at the college, made an informal debut here Wednesday night at the Louis-Nikolais Dance Theater Lab, 344 West 36th Street.

This may not represent the Dartmouth some old grads know. Luckily, nothing is sacred. The involvement and enthusiasm shown by the four — two june '71 graduates, Robb Pendleton and Jonathan Wolken, Robby Barnett '72 and Lee Harris '73 — suggest an interest in dance that can only be applauded. The group displayd amazing physical fearlessness, humor, inventiveness,

appeared here by invitation and is not performing on the professional concert circuit — it is one the troupe's members themselves might want to take into account. There were times when it seemed they were in danger of confusing athletics with art.

There is a strong tendency in the New York avant-garde to use "natural" as opposed to "traditional" dance movement. Many choreographers deliberately use nondancers today. Often the nondance movement is performed by highly trained dancers. Yet the Pilobolus (the name of a fungus) men rely upon natural movement not only because it obviously appeals to them, but also because they have had no more than one or two terms of dance.

even still more important.

Mr Barnett, for instance, has the makings of a very unusual dancer. The resiliency with which he bounded up from prone positions on the floor and his

MAD Magazine used to sell small printed portraits of Alfred E Neuman, referred to as "suitable for framing or lining your birdcage". The thing I liked about it was that they were sold in powers of 3: "25 cents for one, 60 cents for 3, $1.50 for 9, $4.00 for 27, or $10.00 for 81".

iAvias MecDvr

According to the show guide handed out to attendees of the MacWorld Expo in Boston, 2004 July, exhibitor Avias (site map) showed a new product called "MecDvr", which was described as an input device for converting an NTSC video signal into an MPEG-4 data in real time. I was not at the show myself (I got the show guide from a friend who attended) and have not been able to find independent reports that this product was shown at their booth. If it is real, it does not appear to be shipping yet.

iSub mute bug

In MacOS X versions prior to 10.3, there is a bug in the handling of the volume of ths iSub subwoofer, a USB audio output device. The bug comes from the decision at Apple to treat the iSub as an independent output channel, unrelated to the main "built-in" audio output channel, rather than as a part of the main system audio output. As a result, when you perform an operation to mute the built-in audio, the iSub is not muted.

Operations that mute the built-in audio include: hitting the mute key on the keyboard, or connecting an auxiliary output (such as headphones) to the audio-out jack.

In version 10.3 Apple fixed this bug, but they did not put the fix into the system updates for older systems.

You can mute the audio with:

osascript -e 'set volume 0'

and unmute with:

osascript -e 'set volume 5'

(or another similar command with a different volume in place of 5)

You can also use the following, which accomplishes the same thing but might be more compatible with different versions of the AppleScript system:

osascript -e 'tell application "System Events" to set volume 0'

To make the scripts useful they have to be bound to a keyboard function key. In MacOS X version 10.1.x, you can use the excellent freeware utility Xkeys by David Stark to do this. On my iMac, running 10.2, I used function key F3 to mute and F5 to set the volume back to my normal level. I chose these keys because I also have an iBook and those are the keys that mute and raise the volume on the iBook.

In the Finder in Mac OS version 10.3 ("Panther"), you can view the contents of a folder (directory) in three different ways: "Icon View", "List View", and "Column View".

In "List View", you can open a sub-folder (subdirectory) by clicking on a little "triangle" (called the disclosure tab) next to the directory's name. When you do this, the folder's contents appear below it, indented; you can do this to several folders and the effect is like looking at an outline or bullet-list with subheadings.

The "bug" is that, after expanding or collapsing a folder, when you close and re-open the window, the Finder sometimes forgets your changes.

The fix is to use the mouse to collapse or open the sobfolder. If you use the keyboard (right and left arrow keys to open and close, respectively) then the change is regarded as "temporary" and will be forgotten the next time the window is opened.

ASCII art from "My Neighbor Totoro", by [unknown] and Duke Lee