Hi all.
I’m a very basic user of audacity. I’ve used it to top/tail some audio recordings and that’s about it.
I now have some broadcast audio. It’s copied from my pvr to my laptop. On my laptop the file has the extension mp3 but it is actually an mp2.
(The ‘mp3’ won’t play, say on VLC but if I change the extension to mp2 it will play).
I can’t seem to import either the ‘mp3’ or the mp2 version of the file into audacity. All I get is noise.
I would swear that last week I did manage to import the ‘mp3’ and get it to play correctly. IMPORT worked, drag/drop did not. So maybe I imagined that I got it working!
This was AFTER my windows10 updated to the latest version (1803) but BEFORE the '2018-06 Cumulative Update for Windows 10 Version 1803 for x64-based Systems (KB4284835). I don’t know if that has had any impact on this…
Any ideas what I’m now doing wrong? Should I be able to import this radio audio file into audacity? Either with the extension mp3 or mp2?
If I convert the mp2 using vlc to an actual mp3, I can import it into audacity but it would be really nice not to have to do that first…
I have tried mp3DirectCut with the mpglib dll but I don’t seem to have any luck with that either. So I may just not have enough knowledge…?!
Audacity does support importing “normal” MP2 files, so my guess is that it is not a normal MP2 file.
Can you post a short sample file so that we can take a look. Short MP2 files may be attached directly to your forum post (see: https://forum.audacityteam.org/t/how-to-attach-files-to-forum-posts/24026/1)
I’ve recorded a short audio file this morning. Hopefully you can find it here
This is the copied-to-laptop file so I haven’t changed the extension (mp3). It won’t play like this but if you change the extension to mp2 it will play on a media player.
I have played around with the audio files this morning again. If I change the extension to .ts they seem to import into audacity - they sound normal so I can edit them. Not sure why the .ts extension works but .mp2 doesn’t?
I really don’t think I used the .ts extension last week to get the files to import into audacity, considering i wrote myself a little note on how to import the files into audacity I don’t think I would have got the extension wrong… but maybe I did…!
But if you can explain (even briefly) as to why the .mp2 extension won’t import (unless you get it to) but the .ts does, that would be great. Just to add to my little understanding of things! I know the mp3 extension is incorrectly assigned to the file on transfer and that the file is actually mp2 (of some sort?!).
It is MPEG-2 encoded (more accurately it is “MPEG-1 Audio Layer II”). This is what MediaInfo says about it:
General
ID : 4221 (0x107D)
Complete name : .../TestAudio.mp3
Format : BDAV
Format/Info : Blu-ray Video
File size : 18.7 MiB
Duration : 2mn 53s
Overall bit rate mode : Variable
Overall bit rate : 905 Kbps
Audio
ID : 1702 (0x6A6)
Menu ID : 5824 (0x16C0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Mode : Joint stereo
Codec ID : 3
Duration : 2mn 53s
Bit rate mode : Constant
Bit rate : 160 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 3.31 MiB (18%)
Language : English
descriptor_tag_extension : 6
Menu
ID : 1700 (0x6A4)
Menu ID : 5824 (0x16C0)
Duration : 2mn 53s
List : 1702 (0x6A6) (MPEG Audio, English) / 7210 (0x1C2A) () / 7201 (0x1C21) () / 7270 (0x1C66) ()
Language : English
UTC 2018-06-23 18:00:00 : en:A Taste of Funny with Denis Norden / en:Comedy writer Denis Norden with three hours of comic listening, illustrating the impact American humour and the British comedy song had on his career. / show/game show / / 03:00:00 /
UTC 2018-06-27 15:00:00 : en:Wordaholics / en:Natalie Haynes, Michael Rosen, Arthur Smith and Paul Sinha vie for wordy supremacy in the panel game chaired by Gyles Brandreth. From February 2012. Episode 2 of 6. / show/game show / / 00:30:00 /
UTC 2018-06-27 15:30:00 : en:Life, Death and Sex with... / en:...Mike and Sue. The lifestyle show turns its attention to aging and alcohol. Stars Robert Duncan and Jan Ravens. From September 1999. Episode 3 of 6. / show/game show / / 00:30:00 /
UTC 2018-06-27 16:00:00 : en:Ring Around the Bath / en:Willing It Away: Stella's luck goes from bad to worse, as daughter Alison and granny want to move in. Stars Pippa Haywood. From January 2006. Episode 2 of 6. / show/game show / / 00:30:00 /
UTC 2018-06-27 16:30:00 : en:Fags, Mags and Bags / en:Sitcom set in a Glasgow corner shop. 4/6. Crispquilibrium: The Wall of Crisps is rocked by an unwitting political scandal. / show/game show / / 00:30:00 /
UTC 2018-06-27 17:00:00 : en:Alex Garland - The Coma / en:As Carl gets used to his coma world, he looks for triggers to wake him up. Tom Goodman-Hill reads Alex Garland's novel. Episode 3 of 5. / user defined / / 00:30:00 /
UTC 2018-06-27 17:30:00 : en:The Tingle Factor / en:Sir Jonathan Miller explains to Jeremy Nicholas why certain moments in music send a shiver down his spine. From September 1992. / undefined / / 00:30:00 /
so it is not quite a “normal” MP2.
2 min 53 seconds of audio at 160 kbps should have a file size of (120 + 53) x (160 / 8) = 3460 kB = 3.46 Mb.
The actual file size is 19.6 Mb, indicating a lot of other “stuff” in the file that is not proper audio.
When FFmpeg is installed, using Audacity 2.2.2, the file may be imported by doing the following:
“File menu > Import > Audio”
Select “FFmpeg compatible files” as the file type filter
Select the file and click OK.
When the file has been imported, there will probably be a long section of silence before the audio starts. This can be deleted by selecting it and then pressing the DEL key.
When FFmpeg is installed, using Audacity 2.2.2, the file may be imported by doing the following:
“File menu > Import > Audio”
Select “FFmpeg compatible files” as the file type filter
Select the file and click OK.
So the construction (header) information is freaking out the automatic sensors and they’re getting it wrong? Forcing it to consult FFMpeg straightens it out?
Audacity expects files to be well formed. If the file says that it is MPEG1, then Audacity will try to read it as a normal MPEG1 file.
FFmpeg tries harder and looks for “any” valid stream(s) within the file. It would be unfair to call FFmpeg a one-trick pony, but it is certainly highly specialised software containing much arcane wizardry.