Data Stored in DASYLab Format is Larger Than Expected?
Problem: Why is data stored in DASYLab Format taking up more space than expected?
Solution: The amount of data that the computer has to manage is based in part on the relationship between sampling rate and block size. Each data block has a 26 Byte header. A block containing only one sample actually has 26 Bytes of overhead for each 4 Bytes of data. The example below shows the relationship:
Block Size: 1, Sampling Rate: 1000 Hz, Duration: 60 Minutes
Useful Data: 4 Bytes * 1000 Hz * 3600 s = 14,400,000 Bytes
Header: 26 Bytes * 1000 Hz * 3600 s = 93,600,000 Bytes
Total Bytes: approximately 103 MB
Block Size: 512, Sampling Rate: 1000 Hz, Duration: 60 Minutes
Useful Data: 4 Bytes * 1000 Hz * 3600 s = 14,400,000 Bytes
Header: 26 Bytes * 1000 Hz / 512 * 3600 s = 182,812 Bytes
Total Bytes: approximately 13.9 MB
This relationship is valid for storage on the hard disk, provided the DASYLab Format is used. When you are storing data for a long duration, the right selection of block size has a considerable effect on the required storage area.
Add Your Comments