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Transcribed police scanners in real-time

murph.live

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Re: Transcribed police scanners in real-time

#71

Post by haram_masala »

MengYuanLong wrote: post #57
VWWHFSfQ wrote: post #53

The speech-to-text transcription is so incredibly wrong that it's almost dangerous to publish it like this. For instance: > at the beach view new screen for assistance there is a needle in his hand he's foaming from his mouth throwing off this item What the officer actually said on the radio: > He was going to Rainier Beach area. A request for assistance to approach two people with needles. : Call was from a neighbor…

I don't have familiarity with speech-to-text but wouldn't it be possible to weight words based on their probability in this application to help resolve this. For example, suspect is probably a low frequency word in normal speech but very high in radio chatter.

You could actually borrow some techniques from text mining to do this, e.g. probabilistic latent semantic analysis, to constantly re-train your speech recognition model by reinforcing translations that semantically "make sense."

Re: Transcribed police scanners in real-time

#72

Post by rasz »

MengYuanLong wrote: post #57
VWWHFSfQ wrote: post #53

The speech-to-text transcription is so incredibly wrong that it's almost dangerous to publish it like this. For instance: > at the beach view new screen for assistance there is a needle in his hand he's foaming from his mouth throwing off this item What the officer actually said on the radio: > He was going to Rainier Beach area. A request for assistance to approach two people with needles. : Call was from a neighbor…

I don't have familiarity with speech-to-text but wouldn't it be possible to weight words based on their probability in this application to help resolve this. For example, suspect is probably a low frequency word in normal speech but very high in radio chatter.

apple dictation does this, it will change already transcribed text mid sentence if it thinks something else fits better

https://news.ycombinator.com/item?id=23322321

at 33 second mark https://twitter.com/jamescham/status/1265512829806927873

Re: Transcribed police scanners in real-time

#73

Post by rasz »

optimumsuave wrote: post #69

Hello Hacker News!!! I am the developer of murph.live - I just want to thank all of you for taking the time to check it out and give us excellent feedback. I stumbled upon this post and now have goosebumps. This started by listening to police scanners throughout the night during recent protests in Seattle, WA. I wanted to help and I immediately put my credit card down for Google's Speech to Text API. As for the inbou…

https://news.ycombinator.com/item?id=23322321 first comment might be of interest

Re: Transcribed police scanners in real-time

#74

Post by VWWHFSfQ »

amluto wrote: post #66
MengYuanLong wrote: post #57

Earlier quoted context omitted.

I don't have familiarity with speech-to-text but wouldn't it be possible to weight words based on their probability in this application to help resolve this. For example, suspect is probably a low frequency word in normal speech but very high in radio chatter.

This needs care. Imagine if you accidentally trained a model that added racism when none was present in the audio.

Or used a weird model like this one which does some sort of Markov chaining to complete sentences that weren't even present in the original audio or transcription.

"foaming at the mouth" was never even close to being uttered on the radio. I'm guessing the (flawed) model inserted that part because of the proximity to the word "needle" and "assistance".

Maybe? No idea.. this website it totally fucked.

Re: Transcribed police scanners in real-time

#75

Post by optimumsuave »

lunixbochs wrote: post #12
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…

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…

Hi lunixbochs!

Your prototype is amazing! The quality of transcription is definitely better than ours via Google.

After we did some legal research we wanted to avoid storing the recordings and rather solely transcription text. Giving access to a platform for humans to verify the transcriptions and in turn train the model is a great idea.

I have started working on getting some pre-trained models set up. I am trying to implement them with wav2letter, deepspeech, kaldi, vosk, etc. - I just need to be pointed in the right direction.

Raspberry Pi's were something I was considering as well - small energy footprint and powerful enough to run these models.

Do you have any advice on ML or acoustic models to avoid? I am working with the 100 hour dataset now.

Thanks!

Re: Transcribed police scanners in real-time

#76

Post by optimumsuave »

VWWHFSfQ wrote: post #74
amluto wrote: post #66

Earlier quoted context omitted.

This needs care. Imagine if you accidentally trained a model that added racism when none was present in the audio.

Or used a weird model like this one which does some sort of Markov chaining to complete sentences that weren't even present in the original audio or transcription. "foaming at the mouth" was never even close to being uttered on the radio. I'm guessing the (flawed) model inserted that part because of the proximity to the word "needle" and "assistance". Maybe? No idea.. this website it totally fucked.

Hello!

The quality is currently limited by Google's API. I am working on getting some pre-trained models implemented, but voice processing is not my speciality as a software engineer.

I do NOT want to spread misinformation nor do we want to unjustly slander anyone. Tonight I will be adding a disclaimer mentioning the limitations of our service and will make sure it is forefront on the website.

Hopefully we can create a model which can deliver better results.

Re: Transcribed police scanners in real-time

#77

Post by optimumsuave »

Developer of murph.live here again - after reading this thread I have some ideas I'd like to vet with everyone here.

1. We need to post links to the source of the stream. I neglected to do that for fear of cease and desist, but now I realize we need to create accountability on our own platform. I will be contacting broadcastify.com to ensure we can direct users to a source.

2. We need a disclaimer on the site directly in your face. I agree with everyone here - this could potentially spread misinformation and do more harm than intended. These transcripts should be read with caution. Additional messaging from us is a must.

3. We need a better acoustic model. Google is too much $$$ and although I'm an engineer, I'm not a linguistics machine learning expert. Can anyone help me with this please?

Our mission was to create transparency into our government - not cause harm. There is a lot of responsibility creating a tool like this and we want to get it right.

With that being said, this site blew up in a few hours. I'm overwhelmed. Please let me know if you'd like to help. Thank you to everyone for the feedback so far - it all helps immensely.

Re: Transcribed police scanners in real-time

#78

Post by kube-system »

lobster45 wrote: post #30
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.

Criminals

I hear people say this from time to time, but I don't think I've ever heard anything actually said on a scanner that would be plausibly useful to a criminal.

Re: Transcribed police scanners in real-time

#80

Post by runawaybottle »

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.

Accuracy is a little wonky even with real speech to text toolkits like Kaldi (which I’ll mention is a pain to even get started with it).

I’ve had some decent results with the following:

https://cmusphinx.github.io/

I have to research how to hand tag my own samples to see if that offers significant accuracy improvements (let’s say I want to accurately transcribe one voice consistently).

Google and Watson APIs are not too free, and I believe Watson has a audio length limit (possibly limited by free tier, or possibly limited in general for all tiers).

Cool to see some real world attempts using this stuff.

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