Camtasia Recording
Recording a video from your screen is not all that complicated from a technical standpoint. All it takes is a program running in the background that copies all or part of the video display buffer’s memory every so often. For 15 frames per second, it would need to grab and store a copy of the data every 60 milliseconds. In other words, it needs to do a full or partial screen capture 15 or 30 times a second (depending on your needs), consistently, without missing a beat, and without eating up all of your excess CPU bandwidth in the process.  All screen recording programs work this way.
One thing that sets screen recording programs apart is how efficiently they use disk space. Capturig and saving 15 or 30 screen snapshots every second, for perhaps up to an hour or more, can generate a LOT of data! This data needs to be saved on your hard drive and processed later on. That’s because the processing needed is far more than can be accomodated on-the-fly as the program is recording. Well, maybe it could, but it would be stealing valueable CPU resources from the program you’re trying to film. That’s not good. 
The thing that made Camtasia the big dog in this industry is the fact that they came up with a very innovative, and FAST, means of compressing each of the screen snapshots so that they don’t take up an unusually large amount of disk space. This allows it to save more data with less overhead.
It’s also part of the reason that Camtasia can handle a bunch of other things at the same time:
- Recording an audio soundtrack
- Zoom and Pan
- Watermarks
- Captions
- Time and Date-stamp images
- Highlight mouse clicks both visually and aurally
- Show the mouse cursor movements
- Free-hand drawings
Sure, there are free screen recording programs, but none of them contain anywhere near the features you’ll find at your disposal with the real deal!
Sunday 17 Sep 2006 | ToolWiz | Camtasia, Tools, Video