Capturing Movies

CaveX allows you to capture the scenes and actions that appear on the screen to a Windows AVI movie files. Windows AVI movie files are useful because they can be viewed with the Windows Media Player, usually just by clicking on the file. They can also be viewed by other movie viewers and you can convert them to MPEG files which can be viewed over the internet.

Begining Movie Capture. To capture the CaveX scenes and animations select the "Edit|Arm AVI Capture" option from the menu bar. Next, you will select a file to save the movie to. This operation "Arms" CaveX, making it ready for video capture. It does not actually begin capturing video.

Triggering Movie Capture. Once the video feature is armed, then you just push the Capture Button on the tool bar. This makes it easy to setup your scene and start the animations before you start making a movie.

Ending Movie Capture. You can stop video capture by clicking on the Capture Button again. Also, the program will stop capturing movie frames when you reach the preset frame limit (see below.)

Movie Capture Options. There are several options that allow you to control the way movies are captured. To change these settings, select the "Settings|Capture Options" from the menu bar. The following a description of the options:

1. Frames Per Second. This option controls the rate at which frames are saved and the rate at which frames will be played back in a movie viewer. This rate is measured in frames per second (FPS). The higher the FPS setting, the smoother the motion will be. However, more FPS, means larger movie files. A rate of 18 FPS is a good compromise.

2. Compression. This option controls the amount of compression that is applied to the images in the file. The higher the number, the more compression and the smaller the movie file. However, the more you compress the file, the poorer the quality of the image. A compression of 35 is a good compromise. Compressions over 50 usually produce poor quality images.

3. Size Limits. AVI files can get very large, especially if you allow the capture to run for a long time. For this reason, CaveX allows you to set a limit to the size of the AVI file. That way, if you accidentally leave the Screen Capture on, the file won't over flow your hard drive.

To enable size limits, check the "Limit Movie Size" checkbox. The limit is specified in the number of frames. Depending on the frame rate, this translates in a specific time length for the movie.

Notes: CaveX attempts to save a new frame everytime a new animation image is drawn on the screen. In order to match the specified frame rate, CaveX will only save a frame if enough time has passed. For example, if CaveX is drawing 100 FPS and you are saving at 10, only one in every 10 frames will be saved.

Conversely, if CaveX is displaying less FPS than you have specified for your movie file, CaveX will save every frame. For example if you are saving at 10 FPS and the CaveX is only display at 5 FPS, CaveX will save every frame. However, since CaveX is saving fewer frames in the same time period, the movie will be speeded up when you play it back.