This page describes how to weave a series of bitmaps files together to create an animation. (The Results environment can make an animation file, .avi, automatically. This page pertains to bitmap files only.)
Most Autodesk Simulation graphics programs provide one or more ways to create a bitmap file. The file format is the standard Microsoft Windows bitmap file (.bmp file). In addition, you can use the Copy command from the Edit menu (in the Windows menu bar) to copy all or a portion of the screen to the Windows Clipboard for pasting into the bitmap editor of your choice (for example, Paint).
If you have a series of sequentially numbered .bmp files of the format xxxxxxnnn.bmp, where xxxxxx is a base name and nnn is a three-digit id starting with 001, then you can use the .bmp-to-.avi converter to create a Microsoft animation file (.avi file).
Convert .bmp to .avi
The .bmp-to-.avi converter, bmp2avi is a general-purpose utility for converting a series of .bmp files into an .avi file. In this way, static screen captures can be converted into an animated sequence.
Before running, you must make certain that the names for your .bmp files:
- are numerically ordered in a sequence with no gaps, starting with 001 and going up to a maximum of 999
- all have the same prefix immediately preceding the sequence number
- all have a .bmp extension
You can name your files manually, with an operating system batch file, or by using bitmap operations in the user interface which generate a series of ordered .bmp files.
To run bmp2avi, type the following at a command prompt in the Autodesk Simulation installation directory:
bmp2avi basename nframes framedur
where:
- basename: is the base name of the .bmp files and the name of the output .avi file; specifically, adding 001.bmp should produce the name of the first .bmp file to be converted.
- nframes: is the number of frames; tacking this three-digit number to basename and adding .bmp should give you the last .bmp file to be converted.
- framedur: is the optional frame duration in 10ths of a second; 5 is the default.
Tips for best results
- You will be asked to select a compression format. If you choose to save disk space by selecting something other than Uncompressed, experiment to determine which compression format gives you the most compression without any appreciable loss of picture quality.
- All .bmp files should have the same screen size. If they differ, the first .bmp will be used to determine the .avi frame size, and subsequent frames will be centered or clipped as needed. Depending on your bitmaps, you may find that the padding looks attractive. Clipping will generally not provide satisfactory results, and if it is used, it must be only a small percentage of the picture.
- If you want an .avi file which will display nicely for all graphics card resolutions, then create your .bmp files in the lowest resolution (e.g., 640x480) with the window maximized. The window will appear smaller on the higher resolutions, but no pixels will be lost or interpolated at any screen resolution. If you create a screen which is too large for lower resolutions, Microsoft's interpolation algorithm will produce non-optimal displays at the lower resolutions.