Waveform data thinning

An apparatus for reducing storage space required for storing vibration waveform data on a non-transitory storage medium, the apparatus comprising:

• an input for receiving waveform vibration data,
• a processor for dividing the waveform vibration data into sequential blocks, and
• for each sequential block, each serially designated in turn as a current block,
• when the current block is also a first block, passing the current block as a reference block to at least one of a memory, a storage, and an output,
• computing a representative value for the current block,
• comparing the representative value for the current block to the representative value for the reference block to determine a difference,
• comparing the representative value for the current block to a minimum representative value,
• transforming the current block into a spectrum,
• comparing the spectrum for the current block to the spectrum for the reference block to determine a correlation value, and
• when the representative value for the current block is above the minimum representative value, passing the current block as the reference block whenever at least one of the following is true,
• the first difference is greater than a given difference,
• the correlation value is less than a given correlation value, and
• a number of blocks between the current block and a most recently passed reference block is greater than a given maximum, and
• storing all of the reference blocks on then on-transitory storage medium as a thinned representation of the vibration waveform data.

A non-transitory computer-readable storage media comprising instructional steps that when performed by the computer reduces storage space required for storing vibration waveform data one a non-transitory storage medium, by causing the computer to:

• receive the waveform vibration data,
• divide the waveform vibration data into sequential blocks, and
• for each sequential block, each serially designated in turn as a current block,
• when the current block is also a first block, pass the current block as a reference block,
• compute a representative value for the current block,
• compare the representative value for the current block to the representative value for the reference block to determine a difference,
• compare the representative value for the current block to a minimum representative value,
• transform the current block into a spectrum,
• compare the spectrum for the current block to the spectrum for the reference block to determine a correlation value, and
• when the representative value for the current block is above the minimum representative value, pass the current block as the reference block whenever at least one of the following is true,
• the first difference is greater than a given difference,
• the correlation value is less than a given correlation value, and
• a numerical count of blocks between the current block and a most recently passed reference block is greater than a given maximum, and
• storing all of the reference blocks on the non-transitory storage medium as a thinned representation of the vibration waveform data.