Bugzilla – Bug 21
16-bit WAV/AIFF imported as noise into 24-bit projects when Preferences were set to copy in the data
Last modified: 2018-08-20 11:54:01 UTC
* GA: Much of the time, 1.3.7 or later on Windows cannot be relied on to import files exported with the explicit "AIFF (Apple) signed 16 bit PCM" filter. Appears to affect exports from recorded data (at any Defauit Sample Rate), or from tones generated at 24-bit. Same problem occurs with the AIFF 24-bit option accessed with "Options" button, but not apparently the comparable 16-bit option. Export Multiple seems affected the same way as regular export. Tested at 44100 Hz, reading directly. On Mac, a user 22 March 09 reports 1.3.7 "suddenly" producing noise when importing AIFF files where it did not before in many similar imports - user changed default sample format to 24-bit at about the same time. More details here. * LL: Gale, have you been able to find a pattern to recreate this? I've tried numerous variations on OSX and Windows and it always seems to import ok. * GA: Are you using a release build? In ANSI Release from HEAD, I created a chirp tone in 24-bit quality, recorded it using stereo mix then exported only the recorded track using the explicit (no options available) AIFF (Apple) signed 16-bit PCM choice. I changed Quality to 32-bit, closed the tracks and repeated the generation, record and export. I am not getting noise on importing the files back into Audacity but what I can replicate is that about half the time the files will crash both HEAD and 1.3.7 Unicode Release; if they don't crash they import properly. So behaviour compared to when I last tested is not the same. I have tried importing with the "All supported files" and "FFmpeg-compatible files" filter and the problem is identical. In 1.2.6 I can import these files dozens of times without problem.
I think 24-bit mode is likely to be implicated in this - I'm willing to be proved wrong, but I'd like a report that definitely had Audacity in 32-bit internal data mode (or 16-bit, if we know that). In this case it wouldn't be a regression, because 24-bit mode has been at least partly broken since the dawn of time, largely because no-one involved in development uses it.
Not in wiki as of 29-Jan-2010
* GA: Michael fixed a specific problem November09 where 16-bit WAV/AIFF imported as noise into 24-bit projects when Preferences were set to copy in the data. However that wasn't 100% replicable for me on Windows (before that fix, 16-bit WAVs from a CD ripper would sometimes import OK into "copy in" 24-bit projects). Now moved to http://bugzilla.audacityteam.org/show_bug.cgi?id=35 where for a few users, AIFF and WAV crash regularly on import, using (they say) initialised preferences.