Re: [Audacity-devel] Bug Fixing - much progress!

[Gale A. <ga...@au...>]

| From Martyn Shaw <mar...@go...> 
| Thu, 18 Dec 2008 23:20:59 +0000
| Subject: [Audacity-devel] Bug Fixing - much progress!
> Gale Andrews wrote:
> > | From Leland <le...@au...> 
> > | Thu, 18 Dec 2008 01:08:54 -0600
> > | Subject: [Audacity-devel] Bug Fixing - much progress!
> >>> Martyn wrote:
> >>> one to be verified on non-windows (Muting/soloing specific stereo 
> >>> tracks when exporting)
> >> What should be checked?  If I'm understanding it correctly, if you have 
> >> 2 tracks and one is muted and you export, then ONLY the unmuted track 
> >> gets exported?
> > 
> > That's right.
> > 
> >> Some things I've tried...all with 2 selected mono tracks....
> > 
> > There are a lot of permutations, and some issues seemed to require 
> > more than two tracks to trigger, and were highly unpredictable 
> > once you fiddled with them mute/solo buttons. Drove me mad. 
> > 
> > The issue as reported was with *stereo* tracks. I presume Martyn 
> > checked on stereo tracks but will try to take a quick look as well to
> > be completely sure.   
> 
> The problem was with stereo (linked) tracks.  When you clicked 'mute' 
> only the first track of the pair had it's 'mute' flag set/cleared. 
> Similarly with 'solo'.  I tested with a stereo chirp, faded in, a 
> stereo DTMF Tones, faded out, mono noise and so on.  That way you can 
> see from the waveforms that it is combining the correct tracks.

Thanks Martyn for that helpful extra info. I had to repurchase several CDs I 
had ripped then edited in Audacity, and sold the CDs, not knowing it had 
exported the files with a channel missing. So forgive my paranoia to check
it's completely right :=) 


> > Here on Windows XP ANSI Release, if I export a muted mono track 
> > (the only one on screen), its a null 44 byte file, and if I drag it back 
> > in, Audacity crashes. So perhaps we need more than a message. 
> > Either create a valid silent file after a prompt, or forbid it altogether
> > (better?)
> 
> I tried this on Unicode-Debug and Release.  I too get a 44 byte file 
> but reading it in doesn't cause a crash on either version.  I checked 
> out the file against 
> http://ccrma.stanford.edu/courses/422/projects/WaveFormat/ and the 
> file looks byte for byte perfect to me.  What differences do we have Gale?

I tried Unicode Release from a few days ago. 

*  Imported stereo 4 minute WAV 44100 Hz 16-bit at 32-bit quality. 
*  Tracks > Stereo Track to Mono
*  Depress Mute 
*  File > Export > WAV (Microsoft) 16 bit PCM, 44100 Hz rate
*  No progress dialogue (that you can see) 
*  Exported file is 66 bytes: crash.wav on
    http://www.gaclrecords.org.uk/audacitytestfiles.html 

What happens now is as follows. If I drag the file in, nothing happens 
and I get a "doing" if I try to click on a menu or anywhere else. If I
task switch away (ALT + TAB), Audacity disappears from Task Switcher 
window. It still has a tab in Taskbar which makes the program reappear
but there is nothing you can do with it except force quit.      

If I File > Import the file, VS pops up offering to debug the crash:  
"unhandled win32 exception [3668]"    

Repeated with another similar file and get a 44 byte file on export this time 
(?) which also crashes. 

Now generate a 3 second mono DTMF tone, mute it, export as WAV as above,  
44 byte file crashes Audacity on import.



Gale