From 3dc4f9767b5de135fa8694ce2c5abbac82192bf5 Mon Sep 17 00:00:00 2001
From: Leonardo Robol <leo@robol.it>
Date: Wed, 3 Mar 2010 16:35:32 +0100
Subject: [PATCH] Risolto un problema con la convoluzione che impediva a molti
 filtri di funzionare.

---
 Filtering/Filtering.py |  9 ++++++---
 Filtering/Splitting.py | 12 ++++++------
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/Filtering/Filtering.py b/Filtering/Filtering.py
index b7ad706..d02827a 100644
--- a/Filtering/Filtering.py
+++ b/Filtering/Filtering.py
@@ -25,8 +25,11 @@ class FIR(AbstractFilter):
     
     def __call__(self, samples):
         """Apply the FIR to samples"""
-        return convolve (self.coefficients,
-                         samples, 'same')
+        # Per tronchiamo brutalmente la convoluzione, anche se 
+        # questo vuol dire perdere dei samples finali. d'altronde
+        # sembra essere l'unico modo per prevere i delay. 
+        sz = len(samples)
+        return convolve (self.coefficients, samples)[0:sz]
 
 
     def GetResponse(self):
@@ -188,7 +191,7 @@ class FilterBank():
             # Sfortunatamente questo ci rovinerà tutta l'ultima parte del 
             # segnale, ma per ora non vedo una soluzione comoda. 
             print "Rolling! Yepeee!"
-            low = roll(low, -1)
+            low = roll(low, -1 * self.length)
 
         return low
             
diff --git a/Filtering/Splitting.py b/Filtering/Splitting.py
index d017313..80168a8 100755
--- a/Filtering/Splitting.py
+++ b/Filtering/Splitting.py
@@ -17,8 +17,8 @@ class SplittingExample():
 
         # Scelgo la filterbank da utilizzare
         # filterBank = Filtering.HaarFilterBank
-        filterBank = Filtering.DaubechiesFilterBank
-        # filterBank = Filtering.StrangFilterBank
+        # filterBank = Filtering.DaubechiesFilterBank
+        filterBank = Filtering.StrangFilterBank
         filterBank.SetDepth(8)
         
         samples = self.LoadSamples ("sunny.pcm")
@@ -29,10 +29,10 @@ class SplittingExample():
             self.Show (wavelets)
 
             
-
-        rebuilt = filterBank.Rebuild (wavelets)
-        Output ("||rebuilt - samples|| = %f" % norm(rebuilt - samples[0:len(rebuilt)]))
-        self.WriteSamples(rebuilt, "rebuilt.pcm")
+        if len(sys.argv) > 1 and sys.argv[1] == "rebuild":
+            rebuilt = filterBank.Rebuild (wavelets)
+            Output ("||rebuilt - samples|| = %f" % norm(rebuilt - samples[0:len(rebuilt)]))
+            self.WriteSamples(rebuilt, "rebuilt.pcm")
 
 
     def LoadSamples(self, filename = "sunny.pcm"):
-- 
2.1.4