Binary Data from .ook

[Crsarmv7l]

I have an .ook file that I would like to be able to extract the binary data from, and would like to understand the process so I can apply it to other files.

I have referred to this, as well as read the whole primer many times:
https://triq.org/rtl_433/IQ_FORMATS.html#i-q-sample-data-formats

as well as searched the repo for .ook and read the relevant .h header files.

I understand that the header of the .ook format contains informational data, and that the actual data contains a number for pulse duration and another for gap duration.

I assume you look at the data to figure out the type of signal?

Using the as an example:
;pulse data ;version 1 ;timescale 1us ;created 2023-03-07 14:29:31-0500 ;ook 369 pulses ;freq1 433911648 ;centerfreq 433920000 Hz ;samplerate 250000 Hz ;sampledepth 8 bits ;range 42.1 dB ;rssi -0.1 dB ;snr 21.4 dB ;noise -21.5 dB 548 996 500 992 500 1004 492 1976 496 1972 504 1972 500 1980 488 1004 524 1972 496 1000 500 992 504 1000 488 996 504 1004 496 988 504 1004 488 1972 504 1000 488 1976 500 1972 504 1976 496 984

I see that the pulse durations are all roughly 500, with the exception of the first pulse at 548, while the gap durations seem to vary. It kind of looks like PPM (this sample is from Nexus which is PPM) . But I was hoping for a little clarity and maybe an explanation ?

Thanks for any help

[zuckschwerdt]

The concept you are looking for is "bit slicer". Basically you need to make some assumptions about the signal (e.g. PPM), recover the timing (e.g. each pulse is a clock) and collect resulting bits.

[Crsarmv7l]

Thanks, that jives with what I suspected.

[Crsarmv7l]

One more question. How is freq1 calculated for the .ook file?

[zuckschwerdt]

The estimated signal frequency is an average over the instant phase angle.

[Crsarmv7l]

Awesome, thank you again