For hydrophone spectral data MAT file data products:

This option affects hydrophone spectral data MAT files only. It's primary purpose is to allow users to specify the time and frequency resolution of the spectral data, including being able access the data that is plotted in the spectrogram PNG/PDF data products (Spectrogram resolution option). The spectrogram resolution option is used by the ONC Data Analytics and Quality team for automated quality assurance of hydrophone data. Spectral data produced by the spectrogram resolution option is downsampled to closely match the the size of the standard spectrogram image (1200 by 900 pixels minus the bezel) as noted in the MAT file itself (see SpectData.processingComment). The third option provides the full resolution spectral data as determined by the calibration and sample rate of the hydrophone (spectrogram resolution MAT files are usually about 1/10th the size of the full resolution. The full resolution is 0.5 seconds or better in time and usually has 1 Hz frequency bins). The default option returns the pre-generated one-minute averaged spectral data MAT file and since these files already exist, most searches complete in seconds. The one-minute average file may also have downsampled frequency bins to best work as source data for the spectral probability density plots and products. If users select the spectrogram or full resolution option, the Spectrogram Concatenation option will be hidden as it is not applicable to either and one spectral data MAT file is generated for every source audio file (essentially the "None" concatenation option). Spectrogram and full resolution spectral data is not pre-generated, so it has to be generated on-the-fly, which can be quite slow: about 25 seconds per every 5 minute source audio file or two hours computation time per day of data. Limit search requests when using the non-default options to one month at a time or use the dataProductDelivery Service to request small amounts of data as your code processes it.

File-name mode field

If the non-default options are selected, the file-name names will have "_plotRes" or '_fullRes" appended to them, for spectrogram resolution or full resolution respectively.

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