Rune Allnor wrote:
> Richard Owlett <rowlett@atlascomm.net> wrote in message news:<vqa9fobci8a3f2@corp.supernews.com>...
> 
>>I've installed Scilab, I act on advice eventually ;}
>>My goal is to get a feel for what speech "looks like" ; personal education
>>[ If successful I may rediscover fire and reinvent a few wheels. ]
> 
> 
> Personally, I "rediscovered fire" when I was four years old. Somebody 
> had left a box of mathces by the fireplace, and I had to check if the 
> mathces worked. They did. I was lucky enough to get away with only a 
> blister on my finger, but the carpet got some burns.
> 
> 
>>What I want to do is plot many of these on same plot by offsetting 
>>into my data file.
>>What I want as output would be a "surface" plotted (x,y,z would be 
>>frequency, amplitude, time)
>>
>>I see how to get a matrix representing the points I wish to plot by
>>changing   v=x(1:points); to v=x(1stpoint:lastpoint) internal to an 
>>appropriate loop.
>>
>>How to plot it ?
>>Thank you.
> 
> 
> I'm not sure if your question concerns getting scilab to do what 
> you want (in which cas I can't help) or if you want input on good 
> ways of visualizing these kinds of data. I take a chance on the latter.
> 

The former.
At least I'm reinenting a useful wheel;) You described what I was 
trying to accomplish.

Richard Owlett <rowlett@atlascomm.net> wrote in message news:<vqa9fobci8a3f2@corp.supernews.com>...
> I've installed Scilab, I act on advice eventually ;}
> My goal is to get a feel for what speech "looks like" ; personal education
> [ If successful I may rediscover fire and reinvent a few wheels. ]

Personally, I "rediscovered fire" when I was four years old. Somebody 
had left a box of mathces by the fireplace, and I had to check if the 
mathces worked. They did. I was lucky enough to get away with only a 
blister on my finger, but the carpet got some burns.

> What I want to do is plot many of these on same plot by offsetting 
> into my data file.
> What I want as output would be a "surface" plotted (x,y,z would be 
> frequency, amplitude, time)
> 
> I see how to get a matrix representing the points I wish to plot by
> changing   v=x(1:points); to v=x(1stpoint:lastpoint) internal to an 
> appropriate loop.
> 
> How to plot it ?
> Thank you.

I'm not sure if your question concerns getting scilab to do what 
you want (in which cas I can't help) or if you want input on good 
ways of visualizing these kinds of data. I take a chance on the latter.

One way of plotting would be a spectrogram. Now, I don't know scilab 
so I don't know the appropriate syntax, and I can only assume scilab 
has some kind of built-in capacity to plot a matrix as an image. 

I would try to plot a spectrogram of the data according tho this 
pseudocode:

- Determine the number N of "frames" of length M in the data (what you 
  call v above). Allocate space for a matrix SpecGram of size M x N. 
  These frames may or may not overlap.

- Then compute the spectrogram as

  for n=1:N
    SpecGram(n,:)=fft(x(firstpoint:lastpoint))^2;
  end

- Plot the spectrogram as an image:

  image(SpecGram)

Rune

I've installed Scilab, I act on advice eventually ;}
My goal is to get a feel for what speech "looks like" ; personal education
[ If successful I may rediscover fire and reinvent a few wheels. ]

I have a large speech file [ from CD of some one reading ].
I have experimented enough to plot a "power" spectra of a segment of 
the recording.
{stacksize chosen to load input file with room to spare, I've run out 
stack on some of my experiments and this seems to be enough;)

      stacksize(15256000);
      [x,y]=loadwave('C:\ATEST\01mono.wav');
      points=25000 ;
      rate=  44100 ;
      fmax=6000;
      fmin=100;

      v=x(1:points);
      f=abs(fft(v,1));
      i=fmin/rate*points:fmax/rate*points;
      fr=i/points*rate;
      plot2d(fr',f(i)'**2);

What I want to do is plot many of these on same plot by offsetting 
into my data file.
What I want as output would be a "surface" plotted (x,y,z would be 
frequency, amplitude, time)

I see how to get a matrix representing the points I wish to plot by
changing   v=x(1:points); to v=x(1stpoint:lastpoint) internal to an 
appropriate loop.

How to plot it ?
Thank you.