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Transcribed police scanners in real-time

murph.live

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Re: Transcribed police scanners in real-time

#21

Post by lunixbochs »

godzillabrennus wrote: post #20
blantonl wrote: post #6

This is very impressive. I'm the owner of Broadcastify.com, where presumably these streams are being transcribed from. We've dabbled in this space and looked at real-world approaches to taking something like this to market, but transcribing 7000+ streams to text seems like an expensive (computational) and ($$) effort that needs a lot of investigation. Note to mention that the individual lexicons between streams are d…

You could conceivably do this using the text to speech recognition on a Mac using Loopback to capture the stream to a microphone input. https://rogueamoeba.com/loopback/ Someone clever enough could create containers to run the software locally and have many loops running off many streams to many instances of the audio to text feature.

Conventional speech recognition will not have very good accuracy for this sort of task out of the box. You will basically need to do local (as in, based on map location) language modeling, and should probably do custom acoustic modeling as well (training a neural network on what radio speech sounds like).

Re: Transcribed police scanners in real-time

#22

Post by artemisyna »

blantonl wrote: post #6

This is very impressive. I'm the owner of Broadcastify.com, where presumably these streams are being transcribed from. We've dabbled in this space and looked at real-world approaches to taking something like this to market, but transcribing 7000+ streams to text seems like an expensive (computational) and ($$) effort that needs a lot of investigation. Note to mention that the individual lexicons between streams are d…

Not sure how easy/difficult this would be from am implementation perspective, but perhaps transcription could be provided as a pay-as-you-go service. Ie, users could pay into a pool for live transcription of a stream for a certain period of time or to retroactively transcribe specific streams.

I'd have to imagine that stream listening follows some sort of power (or otherwise 80/20) law, so hopefully that would help with the expense?

Re: Transcribed police scanners in real-time

#23

Post by p0sixlang »

blantonl wrote: post #17
lunixbochs wrote: post #12

Earlier quoted context omitted.

I prototyped this concept too, at https://feeds.talonvoice.com with prohibitively expensive Google speech recognition, but also have a feature for users to listen and fix transcriptions. If murph was anything like me they probably paid for broadcastify and tailed a couple of the static mp3 feeds. My plan was to collect user transcription corrections on my site then train my own inexpensive models on them. The open-so…

Our new project, Broadcastify Calls, might be a better fit for this. Instead of 24x7 live streams, we capture and ingest every individual call as a compressed audio file from SDRs (software defined receivers) We can then ingest and present back to consumers playback, rewind, playlist, of those calls. We're now capturing over 100 systems and 800-900 calls a minute... as we solidify the architecture it will be our new…

Hey Blatoni, big fan, and software engineer here. Any way you could add Rochester, NY (Monroe County Sheriff, and RPD) to the list of supported calls? I have an RTL SDR, but haven't been able to spend the time figuring out how to decrypt the Phase II trunking.

Re: Transcribed police scanners in real-time

#25

Post by blantonl »

p0sixlang wrote: post #23
blantonl wrote: post #17

Earlier quoted context omitted.

Our new project, Broadcastify Calls, might be a better fit for this. Instead of 24x7 live streams, we capture and ingest every individual call as a compressed audio file from SDRs (software defined receivers) We can then ingest and present back to consumers playback, rewind, playlist, of those calls. We're now capturing over 100 systems and 800-900 calls a minute... as we solidify the architecture it will be our new…

Hey Blatoni, big fan, and software engineer here. Any way you could add Rochester, NY (Monroe County Sheriff, and RPD) to the list of supported calls? I have an RTL SDR, but haven't been able to spend the time figuring out how to decrypt the Phase II trunking.

You can get started as a calls ingest provider here:

https://wiki.radioreference.com/index.php/Broadcastify-Calls

Re: Transcribed police scanners in real-time

#27

Post by robbiet480 »

atarian wrote: post #24

Apart from the police and people listening out of interest/curiosity, who else taps into police scanners? It seems like a really narrow and competitive niche to be in for developers.

According to Broadcastify (https://www.broadcastify.com/), there's 43k listeners across 7000 streams right now

Re: Transcribed police scanners in real-time

#28

Post by mhh__ »

Is it legal to listen to these in the states?

I know OFCOM (UK FCC) state it's illegal to listen to certain frequencies without permission, which seems delightfully unenforceable (for legal reasons I most definitely do not possess a wideband software defined radio or a similarly sensitive antenna)

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