Well after deleting what seems like hundreds of bloody comment and trackback spams over the past week, I’ve installed Spam Karma (billed as a “fearless Spam Killing Machine”) on this blog. If it’s successful, I’ll be installing it on my other WordPress blogs.

It includes blacklists, captcha or email verification for suspicious comments, a myriad of settings, all that good stuff. For now I’ve set it to “lenient” mode until I get a feel for how strict it is. Feel free to leave junk comments here to see how it goes. (But beware of deliberately leaving spammy comments — for all I know it may decide to blacklist your IP address!

PS. Tuesday 21:25. The manual install as in the ReadMe worked for fine me, except that you can’t get to the config page through the menus, you have to activate it from the plugins page, then go to the URL it quotes. (This is apparently a known thing with WP1.2, but I guess it applies to WP1.2.2 as well, which we’re running here. Presumably it doesn’t apply to the current nightly builds or to the future 1.5.)

Also be sure to try the test captcha page (linked off the config page) to make sure that bit works (eg the correct PHP libraries are there somewhere. If they’re not, I guess you need to hassle your ISP. Works fine for me.)

PS. Wednesday 21:15. There is a hitch: the e-mail it sends out summarising what it’s done is encoded with something. I think this is an incompatibility with the PHP setup on my ISP… the same thing happened with WordPress 1.2′s password reminder messages. I’ll have to dig around for a fix.

It should also be noted that Tony has tried to plonk it onto a blog he runs, and is having some issues. So it’s not all beer and skittles.

On the bright side, it tells me it caught 20 spam comments in the last 24 hours. I certainly haven’t seen any get let through.

PS. Thursday 20:05. Some are getting through, but evidently nowhere near the total number being caught. Hmmm.

Daniel’s favourite file formats for distributing multimedia to friends, on the web, that kind of thing. I know a lot of hardcore geeks will know all this stuff (and disagree with some of it), but I was asked recently about it, so here goes.

For pictures containing large blocks of colour, including most screendumps out of Windows… PNG. GIF used to do the job for this, but PNG supports more than 256 colours, and is now in widespread use. Even Windows XP Paint manages to handle it, though older versions don’t.

For pictures with lots of variance in colour, such as most photos, it’s gotta be… JPEG. Try out the various compression settings to see what works. You can often shrink files down a surprising amount with little in the way of visible detail loss. Of course, keep a pristine copy if it’s a picture you’ll need to work on in the future. Windows XP Paint can do JPEGs… uhh, kind of… no control over compression.

For sound, the cross-platform standard now is MP3. A nice balance of quality and file size. Playback software is standard on any computer of the last 5 years or so (and if not already installed ‘cos it’s some ancient beast, is freely available), and unlike WMA it’s supported on pretty much every portable digital music player ever made. (I’m with Cameron – Microsoft should retire WMA. They won’t, of course.)

Movies? MPEG-1. Don’t get me wrong, I love DivX. DivX good. And in comparison, MPEG-1 is not the most efficient of formats, but even ancient creaking Windows NT Media Player supports it. No mucking about with making people download extra codecs or special players – any setup can handle it. No RealPlayer or Quicktime nagware. No Windows-only WMV that the poor Mac and Linux people can’t handle.

And if you use a decent encoder such as TmpGenC (free!), you can do a fair bit of tweaking so you get a watchable movie that’s not too humungous. Fiddle the bitrates, try a variable bitrate, reduce the frames per second, crop unused parts of frame, use a efficient sound compression. Takes a bit of practice, but worthwhile in my opinion. Hopefully in the near future, more efficient versions such as MPEG-2 and MPEG-4 will become standard on all computers. But in the meantime, I’m sticking with MPEG-1.

Agree? Disagree? Comment?