Sample File

Contents

SPRAAK will read sample files coming in many standard formats, including WAV, SPERE and SUNAU. Sample files are also supported in the native SPRAAK format with typical extension .sam.

SPRAAK also supports sample files stored in raw format (i.e. without any header information). For these files necessary information, such as sampling frequency, can be enterred either as command line arguments are in a single external header for a whole collection (corpus) of files.

SPRAAK supports real-time processing on all kinds of input including physical files, but also on pipes, streams, .. Hence the length of a file does not need to be available at the time of opening or before processing can happen.

Keys

The relevant header keys are:

• DATA: must be set to SAMPLE
• NSAMPLE: the number of samples
• NCHAN: the number of channels
• DIM1: the number of frames
• DIM2: number of samples per frame
• CHANLEN: number of samples
• FSHIFT: frame shift in seconds (default=0.01)
• SAMPLEFREQ: sampling frequency (default=8000)
• TYPE: datatype (default I16)

A value of '-1' always indicates "till the end of file" (physical or not)

Data

Sampled data is stored in natural sequential order, possibly multiplexed at the sample level when dealing with multichannel data.