Spectrum Saver

A set of program for logging spectrum from tinySA / tinySA Ultra & render the logs into spectrogram

WARNING: It's still WIP, code quality is eye-burning.

Cloning:

 $ git clone --recursive https://github.com/NeoChen1024/Spectrum-Saver.git

Dependencies

• A C++20 compiler and standard library with std::format and C++20 chrono parsing support
• ImageMagick with Magick++ development files
• OpenMP
• Google CRC32C, included as a Git submodule
• tinycolormap, included as a Git submodule

Building

$ make
$ make test

Usage:

 $ spsave [options]
	-t <ttydev>
	-m <tinySA Model>	"tinySA" or "tinySA4"
	-s <start freq MHz>
	-e <stop freq MHz>
	-k <step freq kHz>
	-r <RBW in kHz>		consult tinySA.org for supported RBW values
	-p <filename prefix>
	-l <loop?>		0 is false, any other value is true
	-i <interval>		sweep interval in seconds
	-x <max records>	default: 1440, 0 disables log rotation
	-F, --format <format>	text (default) or binary


 $ log2png -f <log file> [-p <filename prefix>] [-t <graph title>] [-g <grid?>]
	[--input-format auto|text|binary]


 $ splogconvert -f <input> -o <output> --output-format text|binary
	[--input-format auto|text|binary] [--model tinySA|tinySA4]

Text remains the default acquisition format during the compatibility period. Binary acquisitions use the .splog extension and preserve the original unsigned 16-bit device samples. Converting a legacy text log to binary requires the device model because the old format does not record its calibration offset. The binary format intentionally leaves records uncompressed to keep acquisition latency, append behavior, and damaged-record recovery predictable. During looping acquisition, SIGINT or SIGTERM finishes any active serial response, resumes the device, drains accepted records, and closes the log.

Example of rendered spectrogram:

Spectrum Log Format:

The current text format is shown below. The versioned binary format is specified in docs/binary-log-format.md.

# Optional comment
$ <start_freq>,<stop_freq>,<steps>,<RBW>,<start_time>,<end_time>
<dBm>
<dBm>
<dBm>
...
<dBm>

$ <start_freq>,<stop_freq>,<steps>,<RBW>,<start_time>,<end_time>
<dBm>
...
<dBm>

Credits

• Google CRC32C for the hardware-accelerated record integrity implementation
• tinycolormap for this awesome colormap library