Opened 2 years ago

Last modified 2 years ago

#8720 reopened enhancement

Support for TETRA audio

Reported by: xd009642 Owned by:
Priority: wish Component: undetermined
Version: git-master Keywords:
Cc: Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

So I had a look in the documentation and searched around and couldn't see any mention about ffmpeg support for TETRA encoded audio and I have a collection of TETRA encoded bit streams that I need to decode and transcode (unfortunately none I can share).

I've attached a link to a page about the standard and a repo with a decoder

https://www.sigidwiki.com/wiki/Terrestrial_Trunked_Radio_(TETRA)
https://gitlab.com/larryth/tetra-kit

Attachments (2)

testfile.acelp (40.4 KB ) - added by xd009642 2 years ago.
ACELP encoded TETRA transmitted audio
output.wav (28.2 KB ) - added by xd009642 2 years ago.
decoded PCM 16 re-encoded as wav

Download all attachments as: .zip

Change History (10)

comment:1 by Elon Musk, 2 years ago

I suggest to close this ticket as there are no will to share samples at all.

comment:2 by Carl Eugen Hoyos, 2 years ago

Resolution: needs_more_info
Status: newclosed

comment:3 by xd009642, 2 years ago

So I'm currently trying to find samples myself for testing as the client unfortunately can't share the files with me either. If I manage to find some could this issue be reopened?

comment:4 by Carl Eugen Hoyos, 2 years ago

Type: enhancementdefect

Please do not reopen this ticket unless samples are provided.

by xd009642, 2 years ago

Attachment: testfile.acelp added

ACELP encoded TETRA transmitted audio

comment:5 by xd009642, 2 years ago

@cehoyos I've attached a file I found here https://github.com/sq5bpf/telive which makes use of the ESTI reference encoder/decoder. However, the ESTI reference contains the notice that "The information contained herein is the property of ETSI and no part may be reproduced or used except as authorised by contract or other written permission. The copyright and the foregoing restriction on reproduction and use extend to all media in which the information may be embodied". So you might not want to look at the code itself for reference I'm unsure of the relevant intellectual property laws.

telive repo also have a file bin/tplay for playing the audio file (using the compiled ETSI artefacts).

I'll leave it up to you if this is enough to reopen the ticket. I can try to provide more information as I find it.

comment:6 by Carl Eugen Hoyos, 2 years ago

Please also provide the expected output.

by xd009642, 2 years ago

Attachment: output.wav added

decoded PCM 16 re-encoded as wav

comment:7 by xd009642, 2 years ago

I took the output 8KHz s16le samples and encoded it as a wav and attached it

comment:8 by Carl Eugen Hoyos, 2 years ago

Priority: normalwish
Resolution: needs_more_info
Status: closedreopened
Type: defectenhancement
Version: unspecifiedgit-master
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