Window Reference
Working with the Compression Dialog Box
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The Compression dialog box gives you tools for testing or `previewing' various compression types on your selected Samples, comparing the original audio to the compressed versions, and assigning your preferred compression type to the Samples.
If the selected Samples have been previously compressed or previewed with the selected compression type, then the compressed size will appear below the list. Notice the difference in compressed and uncompressed size.

Item
Use
1 Compression Types listbox
To select a compression type, click on it. To avoid all data compression, select no compression.

Note: The compression types listed here may vary from Sample to Sample because some of the compression types won't work for certain kinds of Samples - i.e. particular sampling rates, numbers of channels, and/or bit depths.

2 Player 2.0.x and Beatnik Xtra Compatible Types Only checkbox
To ensure that your RMF files' MP3 compression will be backwards-compatible with more versions of the Beatnik Player for Web browsers and the Beatnik Xtra for Macromedia Director, be sure to check this checkbox.

Note: Until such time as later versions of the Beatnik Player become well-distributed, Web developers who require compatibility with the installed base of Beatnik Players should use this option.

Several new MP3 sample compression settings became available in version 2.0, some of which were not supported in the earlier versions. When this item is checked, the Compression Types listbox (1) will only offer those compression types that the Beatnik Player, versions 2.0.x, and the Beatnik Xtra are able to play.

3 Original button
Plays the original, uncompressed version of the Sample.
4 Preview button
Previews the effect of the selected compression type on the indicated Sample, without selecting that type.

Note: If you entered this dialog with multiple Samples selected, a Preview for: menu will appear above the Preview button. Use this menu to indicate which of the selected Samples you want to preview before you click the Preview button.

If the selected Samples haven't yet been compressed with the selected compression type, a Compression Progress dialog box will appear briefly.

During preview playback, the Preview button will change to a Stop button. Use it to cancel playback before the Sample finishes playing.

5 OK button
Applies the selected compression type to the selected Samples, and closes the dialog box.
6 Cancel button
Closes the dialog box without applying the selected compression type.


Setting a Compression Type

To set the compression type for the selected Samples:
  1. If your RMF file will be played in Web pages by the Beatnik Player for Web browsers, and it's important to you that it play with the maximum number of existing users' Beatnik Player installations, then check the Player 2.0.x and Beatnik Xtra Compatible Types Only checkbox.
  2. Select a compression type from the list.
  3. Click the Preview button and listen to the compressed Sample.
  • If this Sample hasn't been compressed with this compression type before, there may be a delay while the Sample is compressed and added to the sample cache (see About the Sample Cache below).
  • Note the difference between the Sample's uncompressed and compressed sizes.
  • You can preview as many different compression types as you like before settling on the one you want to use. If your disk fills up with too many compressed alternatives, use the Clear compression cache dialog box (see About the Sample Cache below).
  1. Once you've decided which compression type to use, select it in the list and click the OK button.
In the Samples tabs of Session windows, a Sample's Compression type will appear after the Sample's name, in parentheses.

About Compression

Compression saves disk space and speeds your listener's download times by reducing the size of the Custom Samples in your exported RMF files.
In a Beatnik Editor Session, compression is treated as a property that's applied to a Sample for the RMF export - your original Sample remains uncompressed, and a compressed copy is generated for use in the RMF file export. That means it's safe to experiment with changing the compression type for any Sample as many times as you like - your original uncompressed Sample is always kept safe in the Session document.

Note: By contrast, earlier versions of the Beatnik Editor would apply compression to the original Sample in the Session file, which could lead to a fidelity loss if you later changed your mind about the compression type.

Such experimentation is usually worth the effort, as different compression types are better suited for different kinds of sounds - some compression types can produce bad-sounding artifacts with some kinds of sound material. You'll want to carefully evaluate how good each compression type sounds to find the best balance between fidelity and file size for each Sample.
The Beatnik Editor supports several different data compression algorithms, including MP3.

Compression Type
Description
No compression
Use the original Sample directly, applying no data compression.
ADPCM compression (IMA 4:1)
Adaptive Delta Pulse-Code Modulation, which reduces files to 25% of original size. Compatible with the International Multimedia Association (IMA) specification.
uLaw 2 to 1
Used on many UNIX-based computers. (Pronounced "mew-law")
aLaw 2 to 1
Used on many UNIX-based computers. (Pronounced "A-law")
MPEG Layer 3
The same compression type used in MP3 files, where the data compression ratio is user-controllable. Higher bit rates provide better sound quality, whereas lower bit rates provide quicker downloads - and you get to set that tradeoff.


About the Sample Cache

For faster comparison of different compression types, the Beatnik Editor preserves every compressed Sample version you've ever previewed in a disk file "cache," instead of re-compressing every time you ask for a preview. If the compression type you want to preview has already been made for that Sample, the cached version is instantly played.
The sample cache ordinarily grows until you close your Session file or quit the Beatnik Editor, at which time it's deleted. If you run out of disk space during a Beatnik Editor session, you can reclaim the cache disk space with the Clear compression cache... command.

Note: Although not encouraged, you can also remove the original, uncompressed Sample from your session with the Delete uncompressed originals dialog box.


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