Wednesday, November 17, 2010

Podcast file name convention

What's in a name? If you're publishing a podcast, the filename used makes a difference. File names must be unique, otherwise your subscribers will overwrite older shows that they may not have listened to yet. The file name should distinguish the show from other subscriptions the subscriber may have, much for the same issue. So, don't use 'episode'. Someone else may do that. Better, is something from the name itself. All In The Mind becomes aim, for example. And this show-unique bit should come first in the name, so the subscriber, using a sorted list, can see all your shows together.

After the show title part of the name should come a numeric part that makes each episode unique. One way to do that is to number them. The first show could be '1', and the second could be '2'. But, such numbers should have leading zeros so that in a sorted list, the lexicographic sort order also is a sequence sort order. So, use '01', at least, so that the first nine episodes sort properly with the tenth. It may be arrogance or optimism to use '001' or '0001' for your first show, suggesting that the expectation is over a hundred or thousand shows. But there are plenty of shows out there with more than one hundred episodes already. And some monthly shows are getting close.

Another way to do this is to encode the date. Some shows use a 2 digit year, 2 digit month, and 2 digit day. For example, 100823 is 2010, August 23rd. This has the advantage that the lexicographic sorting is also the date order. And the sequence won't break for another 90 years. Of course, a 4 digit year such as 20100823 also sorts properly, and won't break sort order for nearly eight thousand years. Either is fine. But i find that the four digit year is easier for a human to read. That is, while one hopes that it's a date, and one hopes that it's in the form of year, month, day for sorting, one must still guess that 10 is the year and not October. Dates come in all the permutations of order, in different cultures. IMO, the military gets it right with YYYYMMDD. While 2010Aug23 may be easier for a human to read, it fails the sort order requirement, and is therefore unacceptable.

Underscores are optional in filenames. aim100823.mp3 is OK. But they must be consistent. You can't use aim100823.mp3 one week and aim_100830.mp3 the next week. This error breaks the sorting order. Best to name these things with a script. Does it matter if the file name is the recording date or publish date? Probably not. There should be a publishing script that gets all the RSS details right. If there is, it could get the file name right as one of those details.

Speaking of underscores, are there characters that should not go into file names? Yes. No colons (:), no slashes (/), and no backslashes (\), because these characters are directory separators on various operating systems. But really, one should stick to alphanumerics, hyphen (-) and underscore. In command line environments, (parenthesis), dots (.), quotes ("'`), brackets (<{[]}>), pipes (|) and so on (~!@#$%^&*+=;?) can all be interpreted, making it difficult (but almost never impossible) to cope. Simply avoid these.

After the sequence number or date, a very brief description of the show may be included. This information can very easily be included in id3 tags within the file - and they should be there. But one or two words will often help the subscriber. Don't make it too long. Windows may have long filenames but DOS does not. And, like it or not, there are mp3 players out there that have 8.3 filenames. So long file names show up as micros~1.mp3 on these players.

What can be included as text within mp3 files? Some of the shows i listen to have complete transcripts. It's incredible.

What if you got it wrong? Should one rename old shows? Absolutely not. Once you've made an error, changing an old filename risks having thousands of podcasting software suites download these old shows again.

This podcast filename convention should also work for any other RSS published material, such as a blog. However, for blogs, the file name length does not have to observe the 8.3 convention. Short file names have mostly gone the way of the dinosaurs. You do use Rock Ridge extensions on your CDs, right?

Monday, November 08, 2010

Binocular spam

I got some spam by email recently.

The Optic 1050 binoculars, with up to 1000x magnification will allow you to see objects up to 35 miles away! The lightweight, rugged and durable Optic 1050 binoculars are only $19.98 and just $7.95 P&H. These super lightweight binoculars easily adjust to your eyes, are shock resistant with shatterproof lenses and feature wide-angle viewing.

Plus, with each pair of binoculars you order, youll also receive the bonus Pocket Spyscope. Its less than 6 inches long with 24x magnification. Thats a $50 value, yours FREE! You just pay $4.95 to cover shipping and handling. The Pocket Spyscope is lightweight and portable. You can see objects up to 7 miles away and it doubles as a magnifying glass for close up use.

National TV Bargains Power Binoculars...

Ignore the missing single quote in youll. Presumably, when they say 1050 binoculars, they're talking about 10x50 binoculars. Read this as "ten by fifty". But it's 10x - ten times larger than your eyes normally see. The big end of the binoculars are 50 millimeters. That's about two inches.

They say up to 1000x magnification. No. They're 10 times magnification. 1000 times magnification with binoculars that have a 2 inch big end would produce a useless, grainy image. For 1000x magnification, the big end would have to be about 20 inches across. And that would be pushing it. I'd really want the big end to be 40 inches across for 1000x. That's how optics work. Naturally, such an instrument would be more expensive, and less portable.

will allow you to see objects up to 35 miles away! How disappointing. I've seen the Andromeda Galaxy without optical aid. That's about two and a half million light years away. One light year is about 6 trillion miles. So Andromeda is more than 15 quintillion miles away. If i can only see 35 miles with these binoculars, but can see 15 quintillion miles without them, there must be something wrong with them.

shatterproof lenses. They must come from Krypton, like Superman.

feature wide-angle viewing. I suppose anything is relative. They're likely wider angle viewing than my telescope at low power. But they're not very wide compared to naked eye. But notice that they don't say what they're relative to. Nor do they give any measure of how wide an angle you can see with them. Normally, binoculars are sold with such a reference. It might be five degrees or seven degrees.

Pocket Spyscope. Its less than 6 inches long with 24x magnification. The length isn't that important. If this Spyscope has a diameter of less than an inch, then the views through it will be grainy. For 24x magnification, it will likely have to be two inches in diameter to be able to produce any kind of decent image. If it's six inches long, it's unlikely to be even an inch in diameter. This is not a $50 value. It's so mis-designed that $5 is too much.

You can see objects up to 7 miles away. So, it's not even as good as the binoculars? Well, that's the truth.

doubles as a magnifying glass for close up use. I think this says something about the way the optics work. I don't think means anything good for use with distant objects.

I have a pair of 10x50 binoculars. They're really good. However, if i want binoculars for hand held use (no tripod), then I find that 8x, or eight times magnification, is about as much as I can handle. With more magnification, the view isn't as steady. But I have a nice tripod. And my 10x50 binoculars work really well on it. I also have a small scope - much more than 6 inches long, and 2 inches in diameter. And it can magnify to something like 24x. But it is totally useless without a tripod. So, my best guess is that this 24x Spyscope is useless.

$19.98 + $7.95 + $4.95 = $32.88. That's the amount you can save by reading this post.

Everything breaks

An odd series of failures seems to have happened all at once. Seals on the oil pump for one car, the water pump, and now it seems, the thermostat of the other car, a printer, and the CPU fan for a computer. The phone. Having redundant hardware isn't enough. Well, nothing lasts forever. But the CPU fan is only maybe five months old. I had expected better. The worst failure, though, is a long lasting cold. Well, there's no fever. But it's been far too long.

This blog has been idle for quite a bit. Lots going on. There are about a dozen posts in the queue. Just have to get time to upload them. Also, i've pretty much abandoned my livejournal blog. The ads that livejoural have added are invasive. I don't like my own site. So, my astronomy stuff will start getting posted here as well in the near future.