Re: Audio playback and classes

[Vytautas Jancauskas]

On Wed, Jul 3, 2013 at 3:35 PM, Mike Miller <address@hidden> wrote:
> On Tue, Jul 2, 2013 at 11:56:03 +0300, Vytautas Jancauskas wrote:
>> All playback modes supported on MATLAB should be working now. It would
>> be great if people tried it out and reported any problems. It should
>> work just like MATLAB classes. The only exception would be 24 bit
>> playback on big endian systems which does not work yet.
>
> I have tested this a bit, haven't reviewed the code yet at all, just
> looking at functionality, and I ran into a couple of problems.
>
> The get(player, {property1, property2}) form returns a matrix instead
> of a cell array:
>
>   octave:3> get (player, {"CurrentSample", "TotalSamples"})
>   ans =
>           0   220500
>
> The return value should rather be
>
>   ans =
>   {
>     [1,1] = 0
>     [1,2] =  220500
>   }
>
> The set(player, ...) function does not accept the struct and cell
> array argument types yet.
>
> I've been able to cause both scrambled sound output and a segfault by
> calling the play and stop function repeatedly, for example:
>
>   octave:1> data = sin (2*pi*440*[0:5*44100-1]/44100)';
>   octave:2> player = audioplayer (data, 44100);
>   octave:3> play (player);
>   ## Do not wait for 5-second tone to finish
>   octave:4> stop (player);
>   octave:5> play (player);
>   ## Now getting scrambled audio output
>
>   octave:1> data = sin (2*pi*440*[0:5*44100-1]/44100)';
>   octave:2> player = audioplayer (data, 44100);
>   octave:3> play (player);
>   ## Do not wait for 5-second tone to finish
>   octave:4> stop (player);
>   octave:5> quit
>   panic: Segmentation fault -- stopping myself...
>
>   octave:1> data = sin (2*pi*440*[0:5*44100-1]/44100)';
>   octave:2> player = audioplayer (data, 44100);
>   octave:3> play (player);
>   ## Do not wait for 5-second tone to finish
>   octave:4> stop (player);
>   octave:5> player = audioplayer (data, 44100);
>   ## Now getting audio output without calling play
>   octave:6> stop (player);
>   panic: Segmentation fault -- stopping myself...
>
> If I wait for playback to finish or use playblocking, I have not seen
> any of these problems.
>
> --
> mike


All those issues should be sorted out now.