1 files changed, 105 insertions, 0 deletions
diff --git a/src/spec2_stretch~.c b/src/spec2_stretch~.c
new file mode 100644
index 0000000..fa5c921
--- /dev/null
+++ b/src/spec2_stretch~.c
@@ -0,0 +1,105 @@
+/* For information on usage and redistribution, and for a DISCLAIMER OF ALL
+* WARRANTIES, see the file, "LICENSE.txt," in this distribution.
+
+iem_spec2 written by Thomas Musil (c) IEM KUG Graz Austria 2002 - 2006 */
+
+#include "m_pd.h"
+#include "iemlib.h"
+
+/* -- spec2_stretch~ - stretch spectral bins --- */
+
+typedef struct spec2_stretch_tilde
+{
+  t_object  x_obj;
+  int       x_blocksize;
+  t_float   x_mul;
+  t_float   *x_spec;
+  t_float   x_msi;
+} t_spec2_stretch_tilde;
+
+t_class *spec2_stretch_tilde_class;
+
+static t_int *spec2_stretch_tilde_perform(t_int *w)
+{
+  t_float *in = (t_float *)(w[1]);
+  t_float *out = (t_float *)(w[2]);
+  t_spec2_stretch_tilde *x = (t_spec2_stretch_tilde *)(w[3]);
+  int i, j, m, n = (t_int)(w[4])+1;
+  t_float yn0, yn1, fract;
+  t_float *spec=x->x_spec;
+  t_float mul=x->x_mul;
+  t_float rcp_mul = 1.0f / mul;
+  
+  for(i=0; i<n; i++)/* copy spec into buffer */
+    spec[i] = in[i];
+  
+  m = (int)((t_float)n * mul);
+  if(m > n)
+    m = n;
+  for(i=0; i<m; i++)/* stretch spec-buffer */
+  {
+    fract = (t_float)i * rcp_mul;
+    j = (int)fract;
+    fract -= (t_float)j;
+    yn0 = spec[j];
+    yn1 = spec[j+1];
+    out[i] = (yn1 - yn0)*fract + yn0;
+  }
+  for(i=m; i<n; i++)/* clear residal of spec-buffer */
+    out[i] = 0.0f;
+  
+  return(w+5);
+}
+
+static void spec2_stretch_tilde_mul(t_spec2_stretch_tilde *x, t_floatarg mul)
+{
+  if(mul <= 0.0f)
+    mul = 1.0f;
+  x->x_mul = mul;
+}
+
+static void spec2_stretch_tilde_dsp(t_spec2_stretch_tilde *x, t_signal **sp)
+{
+  int n = (sp[0]->s_n)/2;
+  
+  if(!x->x_blocksize)
+  {
+    x->x_spec = (t_float *)getbytes((n+1)*sizeof(t_float));
+    x->x_blocksize = n;
+  }
+  else if(x->x_blocksize != n)
+  {
+    x->x_spec = (t_float *)resizebytes(x->x_spec, (x->x_blocksize+1)*sizeof(t_float), (n+1)*sizeof(t_float));
+    x->x_blocksize = n;
+  }
+  dsp_add(spec2_stretch_tilde_perform, 4, sp[0]->s_vec, sp[1]->s_vec, x, n);
+}
+
+static void *spec2_stretch_tilde_new(t_floatarg mul)
+{
+  t_spec2_stretch_tilde *x = (t_spec2_stretch_tilde *)pd_new(spec2_stretch_tilde_class);
+  
+  outlet_new(&x->x_obj, &s_signal);
+  if(mul <= 0.0f)
+    mul = 1.0f;
+  x->x_blocksize = 0;
+  x->x_mul = mul;
+  x->x_spec = (t_float *)0;
+  return (x);
+}
+
+static void spec2_stretch_tilde_free(t_spec2_stretch_tilde *x)
+{
+  if(x->x_spec)
+    freebytes(x->x_spec, (x->x_blocksize+1) * sizeof(t_float));
+}
+
+void spec2_stretch_tilde_setup(void)
+{
+  spec2_stretch_tilde_class = class_new(gensym("spec2_stretch~"), (t_newmethod)spec2_stretch_tilde_new,
+    0, sizeof(t_spec2_stretch_tilde), 0, A_DEFFLOAT, 0);
+  CLASS_MAINSIGNALIN(spec2_stretch_tilde_class, t_spec2_stretch_tilde, x_msi);
+  class_addmethod(spec2_stretch_tilde_class, (t_method)spec2_stretch_tilde_dsp, gensym("dsp"), 0);
+  class_addfloat(spec2_stretch_tilde_class, (t_method)spec2_stretch_tilde_mul);
+  class_sethelpsymbol(spec2_stretch_tilde_class, gensym("iemhelp/spec2_stretch~-help"));
+}