I-D(1)

NAME

i-d - convert 16-bit short integers to doubles

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SYNOPSIS
DESCRIPTION
OPTIONS
EXAMPLES
SEE ALSO
AUTHOR
COPYRIGHT
BUG REPORTS

SYNOPSIS

i-d [-n | scale] < shorts > doubles

i-d reads a stream of native, machine-format 16-bit signed short integers from standard input, multiplies each value by a scale factor, and writes the results to standard output as native, machine-format double-precision floating point numbers.

The optional single argument selects the scaling:

If a numeric scale is given, each input value is multiplied by it. If -n is given, the scale is set to 1.0/32768.0, so that input data spanning the full short integer range maps onto the range -1.0 to +1.0. With no argument the scale defaults to 1.0.

This command is deprecated and scheduled for removal; it prints a deprecation warning on startup. It is the inverse of d-i(1), and is typically used in pipelines with other BRL-CAD signal-processing tools such as dmod(1) and dconv(1).

OPTIONS

-n: Normalize: use a scale of 1.0/32768.0 so that the full 16-bit signed input range maps onto -1.0 to +1.0. Mutually exclusive with a numeric scale argument.
scale: A floating point multiplier applied to every input sample during conversion. A scale of 0.0 is rejected as an error.

EXAMPLES

Example 1. Normalize full-scale short samples to unit-range doubles

i-d -n < signal.pcm > signal.d

Treats the values in signal.pcm as 16-bit signed samples and rescales them to the range -1.0 to +1.0, producing double-precision data in signal.d suitable for further floating point processing.

Example 2. Convert and filter in a processing pipeline

i-d -n < input.shorts | dmod -m 2.0 > louder.d

Converts the 16-bit short stream to normalized doubles, then doubles the amplitude with dmod(1), leaving the result as a double-precision stream in louder.d.