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Anonymous public voicemail inbox

afterthebeep.tel

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Re: Anonymous public voicemail inbox

#11

Post by unixispower »

3-cheese-sundae wrote: post #8

What audio codec and parameters are used for the recordings? You've really nailed the 90s landline sound.

They come from my VoIP provider as 16bit 8kHz WAV files. I crunch them down to MP3s using ffmpeg before uploading. I don't get any say in the source quality, but I'm quite pleased with it as well.

Re: Anonymous public voicemail inbox

#12

Post by ryukoposting »

3-cheese-sundae wrote: post #8

What audio codec and parameters are used for the recordings? You've really nailed the 90s landline sound.

You could probably just apply a 300Hz-3300Hz band-pass filter to any given recording and make it sound really close to analog phone call audio [1]

[1]: https://en.wikipedia.org/wiki/Plain_old_telephone_service#Ch...

Re: Anonymous public voicemail inbox

#15

Post by Zod666 »

unixispower wrote: post #3
swyx wrote: post #2

how is the last message march 31? does this thing update live?

I manually moderate the voicemails and run a script locally to build out a static site and upload it to Neocities. The site is relatively fresh (created within the past year); it just hasn't seen much traffic yet.

If the site blew up in popularity how would you plan to continue moderating the voicemails?

Re: Anonymous public voicemail inbox

#16

Post by ale42 »

unixispower wrote: post #11
3-cheese-sundae wrote: post #8

What audio codec and parameters are used for the recordings? You've really nailed the 90s landline sound.

They come from my VoIP provider as 16bit 8kHz WAV files. I crunch them down to MP3s using ffmpeg before uploading. I don't get any say in the source quality, but I'm quite pleased with it as well.

On the telephone network it was probably µ-law (https://en.wikipedia.org/wiki/%CE%9C-law_algorithm) encoded 8-bit 8 kHz data. This is what was used on the backbone of analog landlines, and now on VoIP for landlines (outside USA and some other countries there's the A-Law, very similar stuff). It's a logarithmic encoding that gives more quality than 8-bit PCM sound while only using 8 bits per sample. If you want to convert it to plain linear data without quality loss then you need 16-bit, whence that comes out from your provider. (µ-law encoded WAV files are also a thing)

> but I'm quite pleased with it as well.

Have to say that despite the filtering of high frequencies making it sound, well, like a telephone... µ/A-law data sounds pretty well. Much better than GSM and most low-bandwidth codecs, especially if the encoded sound is not just pure voice but also background noise that comes with it.

Re: Anonymous public voicemail inbox

#17

Post by nico »

Really cool, thank you for posting

Are you using something like asterisk or FreeSWITCH to connect to the siptrunk? If so, do you have a backend for the dialplan?

Would love to see the code if possible

Re: Anonymous public voicemail inbox

#19

Post by unixispower »

nico wrote: post #17

Really cool, thank you for posting Are you using something like asterisk or FreeSWITCH to connect to the siptrunk? If so, do you have a backend for the dialplan? Would love to see the code if possible

For fun I self-host Asterisk at home, but I'm using a cheap VoIP provider (VoIP.ms) to take the burden of hosting for this project. The code that I did write to pull messages is just some boring API interfacing in a simple Python script: https://gitlab.com/unixispower/after-the-beep/-/blob/main/_u...

Re: Anonymous public voicemail inbox

#20

Post by unixispower »

spxneo wrote: post #18

the voicemails are genuinely wholesome and theme of the 90s, i cracked up at the hot pockets one some more details about stack and implementation would be great too curious how this was built

Site is static built using Jekyll. Voicemail inbox is hosted using VoIP.ms. I pull the voicemails manually by running a Python script, edit the Markdown file that the script spits out to add a memo, then run another script to build and upload the site to Neocities.

I thought about making a dedicated "app" for all of it, but why make it more complicated than it has to be. I manually moderate all the calls anyway, so I just stuck with a simple smattering of scripts and static hosting.

You can see all the site source and scripts here: https://gitlab.com/unixispower/after-the-beep

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