Fifteen subjects were deemed to be enough for a power of 80 as the Cohen effect sizes reported by Trowbridge et al. [ 5] ranged between 0.9 and 1.9 for measures of compression rate and depth.
To judge the conciseness of a key-frame summary a measure of the Compression Ratio (CR) is used [68].
This data was inserted to a series of biomechanical models to calculate a measure of L4-L5 compression and spine stability.
Wavelets are defined by: Open image in new window (E13 where a is the scaling parameter and measures degree of compression, and b is the translation parameter that indicates the time location of the wavelet.
The case where VQM is used to measure a combination of compression and transmission distortions (for example, different QP and packet loss rate with uncompressed reference) is not evaluated in this paper.
The global behavior is compared with the measures of the compression test.
Prior to that, we explored a basic measure of within-genome compression efficiency (CE) by expressing the SNP genotype file sizes in bits before and after data compression by the gzip tool.
Then, we repeated the measures after compression of abdomen using an external band to achieve -10% and -15% of the basal abdominal circumference.
The compressive strength of the bone was measured with a speed of compression of 0.2 mm/s.
While the performance of lossless compression is measured by its degree of compression, lossy compression is also evaluated on the basis of the error it introduces.
Furthermore, as the relation between the wavelet domain coefficients and the measures of the quality of compression [root mean square error (RMSE) and local point error (LPE)] is not straightforward, it is difficult to achieve good control over the quality of compression by specifying thresholds on the wavelet coefficients.
