ssdv/README

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SSDV - simple command line app for encoding / decoding SSDV image data
Created by Philip Heron <phil@sanslogic.co.uk>
http://www.sanslogic.co.uk/ssdv/
A robust packetised version of the JPEG image format.
Uses the Reed-Solomon codec written by Phil Karn, KA9Q.
ENCODING
$ ssdv -e -c TEST01 -i ID input.jpeg output.bin
This encodes the 'input.jpeg' image file into SSDV packets stored in the 'output.bin' file. TEST01 (the callsign, an alphanumeric string up to 6 characters) and ID (a number from 0-255) are encoded into the header of each packet. The ID should be changed for each new image transmitted to allow the decoder to identify when a new image begins.
The output file contains a series of fixed-length SSDV packets (default 256 bytes). Additional data may be transmitted between each packet, the decoder will ignore this.
DECODING
$ ssdv -d input.bin output.jpeg
This decodes a file 'input.bin' containing a series of SSDV packets into the JPEG file 'output.jpeg'.
LIMITATIONS
Only JPEG files are supported, with the following limitations:
- Greyscale or YUV/YCbCr colour formats
- Width and height must be a multiple of 16 (up to a resolution of 4080 x 4080)
- Baseline DCT only
- The total number of MCU blocks must not exceed 65535
INSTALLING
make
TODO
* Allow the decoder to handle multiple images in the input stream.
* Experiment with adaptive or multiple huffman tables.