aptdec/atpdec.1

.TH ATPDEC 1 "Atpdec ATP satellite image decoder"
.SH NAME
atpdec
.SH OVERVIEW
atpdec is a decoder for NOAA weather satellite images (ATP).
It takes soundfiles recorded from an ATP receiver and convert them into .png images.
.SH SYNOPSIS
.B atpdec
.I "[options]" soundfiles ...
.SH OPTIONS
.TP
.br
.B \-c file.png
Use a private colormap for false color generation. Default : Internal colormap.
.TP
.br
.B \-i [r|a|b|c]
Toggle raw (r) , channel A (a) , channel B (b) or false color (c) output.
Default : "abc"
.TP
.br
.B \-d directory
Optional images destination directory. Default : soundfile directory.
.TP
.br
.B \-s
Output 8bits grayscale image for channel A|B and raw images. Default  : 16bits images.

Generated image are in png format, 16 or 8bits greyscale for raw and channel A|B images,
24bits RVB for false color.
Image names are soundfilename-x.png, where x is :
        -r for raw images
        -satellite instrument number (1,2,3A,3B,4,5) for channel A|B images
        -c for false colors.


.SH DESCRIPTION
Atpdec is a open source program that decode images transmitted by POES
NOAA weather satellite serie.
These satellites transmit continuously, among other things, medium resolution
images of the earth on 137Mhz.
These transmitions could be easely received with
an inexpensive antenna and dedicated receiver.
Output from such a receiver, is an audio signal that could be recorded
into a soundfile with any soundcard.

Atpdec will convert these sounfiles into .png images.

For each soundfile up to 4 images could be generated :
1) Raw image : contains the 2 transmitted channel images  + telemetry and synchro pulses.
        Raw image is not calibrated, so it could be too dark or too light depending of
        the recording level.

2) Calibrated channel A image

3) Calibrated channel B image

4) False color image

Input soundfiles must be mono signal sampled at 11025 Hz.
Atpdec use libsnd to read soundfile, so any sound file format supported by libsnd
could be read.


.SH EXAMPLE
atpdec -d image -i ac *.wav

.br
Will process all .wav files in the current directory, generate only channel A and false color images and put them in the image directory.
.SH AUTHOR
Thierry Leconte (2003)