inspectrum

inspectrum is designed for analysing captured signals from software-defined radio (SDR) receivers. It provides visualization capabilities including spectrograms with zoom/pan, plots of amplitude, frequency, phase, and IQ samples, as well as cursors for measuring period, symbol rate, and extracting symbols. Users can export selected time periods, filtered samples, and demodulated data.

The tool supports a wide range of file types such as SigMF recordings (*.sigmf-meta, *.sigmf-data), complex float formats (*.cf32, *.cfile, *.cf64), integer formats (*.cs16, *.cs8, *.cu8), and real samples (*.f32, *.f64, *.s16, *.s8, *.u8). This makes it versatile for processing outputs from tools like GNURadio, osmocom_fft, BladeRF, HackRF, and RTL-SDR.

Key features include support for large files (100GB+ or multi-gigabyte), making it suitable for handling extensive signal captures in radio frequency analysis and reverse engineering scenarios.

inspectrum reads interleaved complex 32-bit float files (e.g., from GNURadio or osmocom_fft) and other supported formats, rendering them as spectrograms with zoom/pan functionality. It generates plots for amplitude, frequency, phase, and IQ samples, allowing cursor-based measurements of signal properties like period and symbol rate. The tool supports exporting filtered or demodulated data from selected time periods, leveraging libraries like FFTW, Liquid, and Qt for signal processing and GUI rendering. The -r flag specifies sample rate in Hz for accurate visualization.