There are 4 conditions that will cause COP to ask you if you want to compress the file:

1. If the book is too large to fit on a CD,
2. If the bit rate is high,
3. If it is in stereo,
4. If the sample rate may not be supported by all DAISY players.

If one or more of these conditions occur, you may be presented with one or more following options:

• Compress to Audio Production Quality: is offered if the book is recorded at a bit rate higher than 128 kbps, or has music and special effect throughout the book.
• Compress to Standard Talking Book Quality: this is the most common option and is offered if the book is smaller than the above rate, or has no music and special effects throughout the books.
• Compress to Acceptable Talking Book Quality: is offered if the book is smaller than the above rate, or has no music and special effects throughout the books.
• Compress to Minimum Talking Book Quality: is offered if the book is smaller than the above rate, or has no music and special effects throughout the books.

The most common option will be Standard Talking Book Quality.

If you are presented with one of the above options:

• Select the button to compress
• Button will disappear and be replaced with plain text that reads: Will Compress to [blank] Quality
• You can Export the File!

Here is a video tutorial on How to Compress a File for Export.