Submission of the homework by email frequently requires using tar, (gzip) compression, and uuencoding. There are public domain programs that implement these utilities on all platforms, thus allowing this standardization.
In order to make these utilities easier to use, we have provided the program uufiles that helps automate the process of packaging files for submission.
On Unix systems the basic tools (tar, gzip, uuencode)
will have already been installed for you. In this case
you will need only to obtain
Once you have uufiles installed you should read the documentation. UUfiles is a script, and so you can just open it and read it. You will find the documentation there. We also have some examples of how to use uufiles.
To install uufiles on a Unix system, just save it in a directory on your PATH and then `chmod 755 uufiles' to make it executable. Or ask your system administrator to install it for you in /usr/local/bin or some other appropriate place.
Be sure to only specify the files that you want to include in the package. We do not want people send their entire home directories to us. UUfiles prints out the list of files it is including in the package. Double check this list to make sure it is what you intended.
There is a public domain encoder and player available from Berkeley. You can ftp the package:
ftp://mm-ftp.cs.berkeley.edu/pub/multimedia/mpeg/bmt1r1.tar.gz
It is well documented.
(If you are only in need of an mpeg player, you may want to try the one at http://www.geom.umn.edu/software/mpeg_play)
The encoder requires that images be in yuv or ppm format. You can use DX to write yuv format images by specifying "yuv" as the format to WriteImage. An example visual program, "write_yuv.net", is included in this directory. It writes a series of yuv-format images: iso.0.yuv, iso.1.yuv, etc.
Use the encoder to create an mpeg file. You need a param file; one is included here, called "default.param". For example:
.../mpeg_encode default.param
Then you can use the player to play the mpeg movie. For example:
.../mpeg_play output.mpg
WHAT IF YOUR MPEG DOESN'T LOOK RIGHT?
Make sure that you are writing only one frame per file (the default behavior of WriteImage yuv format is to append new frames if a file already exists; set the frame parameter to 0 to ensure that new frames overwrite previous frames).
Make sure that you have
BASE_FILE_FORMAT YUV
YUV_FORMAT ABEKAS
in your .param file.
Other files in this directory: