Compressing shockwave file size for internet use

Created and designed by Vivienne Trulock for ilikecake, 2005

You save your work as a Shockwave (DCR) movie to prepare it for playback in a Shockwave-enabled Web browser. Users can be impatient while waiting for large downloads. You need to minimise this as much as possible by compressing files as much as possible.

Image Compression

In the ‘compression’ tab in ‘publish settings’, modify the image compression to JPEG. Test the movie at various JPEG quality settings and choose the one which is the smallest, yet will still yield good quality

Code

Use each piece of code as much as possible. Delete superfluous code from the cast that does the same job as another and reassign the one that’s left to any sprites that used the deleted code. To help you to do this, name each unique behaviour you have written.

Cast Compression

Remove any cast elements that are not used in the final movie: images, sounds, code, text, fields etc…

Compressing Sound

In the ‘compression’ tab in ‘publish settings’ tick the ‘shockwave audio compression enabled’ checkbox. Convert the audio from stereo to mono in the ‘compression’ tab in ‘publish settings’. Reduce the frequency from 44,000 to 22,000 Hz in Soundforge. Again check for quality.

If the file size is still quite large, consider removing large audio files (background music normally) in the shockwave movie, and just leaving in smaller interactive sounds. Experiment with the kbits per second to find the most optimum one for your movie.

Choose the bit rate appropriate for the intended delivery system (modem, ISDN, CD-ROM, hard disk, and so on), the type of movie, and the nature of the sound itself. Voice-over sound quality, for example, may not need to be as high as that of music.

Test the sound on several systems to find the right balance between quality and performance. The more compressed a sound is, the faster it streams. If you choose to use a high quality and low degree of compression, a slow delivery system may not be able to send the data fast enough, resulting in gaps during playback. Most developers choose 16 Kbps for the best results over the Internet. Any sound compressed at less than 48 Kbps is converted to monaural.

User Feedback

In the ‘shockwave’ tab in ‘publish settings’, tick the ‘display progress bar’ option. This makes the user aware of how long the download will take and decreases anxiety.

REMEMBER!!
It’s no use compressing the file so much that it looks or sounds shit!! It’s all about compromise… the smallest file at the best quality. This is a hard assignment because it’s all about sacrificing hard work, taking out bits that you’ve worked hard on etc…

Consider also removing sound you really like, having only some of your game online or breaking the game up into 3/4/5 smaller movies each of which can download separately. Most users will wait if they are sufficiently interested in the download.