From 0f3045f82953249df62f5002f2ba6d454cfc78c8 Mon Sep 17 00:00:00 2001
From: j <0x006A@0x2620.org>
Date: Wed, 7 Mar 2012 15:36:48 +0100
Subject: [PATCH] improve audio timeline, normalize to full width

---
 oxtimeline/audio.py | 109 +++++++++++++++++++-------------------------
 1 file changed, 46 insertions(+), 63 deletions(-)

diff --git a/oxtimeline/audio.py b/oxtimeline/audio.py
index b02fbc5..67bbc02 100644
--- a/oxtimeline/audio.py
+++ b/oxtimeline/audio.py
@@ -13,8 +13,7 @@ import gst
 
 
 class Audio(gst.Pipeline):
-    left    = []
-    right   = []
+    volume  = []
     position = 0
 
     def __init__(self, uri, channels=2):
@@ -34,12 +33,12 @@ class Audio(gst.Pipeline):
         self.queue = gst.element_factory_make("queue")
         self.rate = gst.element_factory_make("audioresample")
         self.conv = gst.element_factory_make("audioconvert")
+        self.level = gst.element_factory_make("level")
+        self.level.props.interval = int(gst.SECOND / self.framerate)
 
         self.sink = gst.element_factory_make("fakesink")
-        self.sink.props.signal_handoffs = True
-        self.sink.connect('handoff', self._data_callback)
 
-        self.add(self.src, self.sbin, self.conv, self.queue, self.rate, self.sink)
+        self.add(self.src, self.sbin, self.conv, self.queue, self.rate, self.level, self.sink)
 
 
         self.src.link(self.sbin)
@@ -61,61 +60,10 @@ class Audio(gst.Pipeline):
             self.conv.link(self.rate,
                            gst.Caps("audio/x-raw-int,channels=%s,width=16,depth=16" %
                                                             (self.channels, )))
-            self.rate.link(self.sink,
+            self.rate.link(self.level,
                            gst.Caps("audio/x-raw-int,rate=%s,channels=%s,width=16,depth=16" %
                                                             (self.samplerate, self.channels)))
-
-    def _data_callback(self, sink, buff, pad):
-        timestamp = buff.timestamp
-        samples = int(buff.size // 2 / self.channels)
-        fmt = "<" + str(samples) + "h"
-
-        data = unpack(fmt, buff.data[:2*samples]) + unpack(fmt, buff.data[2*samples:])
-        n = 0
-        for i in data:
-            if n%2 == 0:
-                self.left.append(i)
-            else:
-                self.right.append(i)
-            n += 1
-
-        samples_per_pixel = int(self.samplerate / self.framerate)
-        while len(self.left) > samples_per_pixel:
-            tile = int(math.floor(float(self.position) / self.input_tile_width))
-            tilePos = int(self.position - (tile * self.input_tile_width))
-
-            def plot(p, start):
-                p = int(p / 256)
-                height = int((p * self.tile_height) / 256) * 2
-                crop = int((self.tile_height-height) / 2)
-                if p: p += 20
-                color = (p, p, p)
-                color = (255,255,255)
-
-                if start:
-                    end = self.tile_height - crop
-                else:
-                    start = crop
-                    end = int(self.tile_height/2)
-                #for i in range(0, self.tile_height):
-                for i in range(start, end):
-                    self.tiles[tile].putpixel((tilePos, i), color)
-            #left
-            pixel = np.asarray(self.left[:samples_per_pixel])
-            self.left = self.left[samples_per_pixel:]
-            p = np.sum(np.abs(pixel)) / samples_per_pixel
-            plot(p, 0)
-
-            #right
-            pixel = np.asarray(self.right[:samples_per_pixel])
-            self.right = self.right[samples_per_pixel:]
-            p = np.sum(np.abs(pixel)) / samples_per_pixel
-            plot(p, int(self.tile_height/2))
-
-            self.position += 1
-
-        if self.mainloop and timestamp >= self.duration:
-            self.done()
+            self.level.link(self.sink)
 
     def getDuration(self):
         if self.duration < 0:
@@ -126,6 +74,21 @@ class Audio(gst.Pipeline):
                   format, self.duration = q.parse_duration()
         return self.duration
 
+    def done(self):
+        pass
+
+    def onBusMessage(self, bus, message):
+        if message.src == self.level:
+            struct = message.structure
+            if struct.get_name() == 'level':
+                self.volume.append((
+                    pow (10, struct['rms'][0] / 20),
+                    pow (10, struct['rms'][1] / 20)
+                ))
+
+        if message.src == self and message.type == gst.MESSAGE_EOS:
+            self.done()
+
 class Timeline(Audio):
     def __init__(self, uri, prefix, width, height):
         Audio.__init__(self, uri)
@@ -150,6 +113,31 @@ class Timeline(Audio):
         self.set_state(gst.STATE_PLAYING)
         self.mainloop.run()
 
+        normalize = 1/max([max(*v) for v in self.volume])
+        for volume in self.volume:
+            tile = int(math.floor(float(self.position) / self.input_tile_width))
+            tilePos = int(self.position - (tile * self.input_tile_width))
+
+            def plot(p, start):
+                height = normalize * p * self.tile_height
+                crop = int((self.tile_height-height) / 2)
+                color = (p, p, p)
+                color = (255,255,255)
+
+                if start:
+                    end = self.tile_height - crop
+                else:
+                    start = crop
+                    end = int(self.tile_height/2)
+                for i in range(start, end):
+                    self.tiles[tile].putpixel((tilePos, i), color)
+            #left
+            plot(volume[0], 0)
+            #right
+            plot(volume[1], int(self.tile_height/2))
+
+            self.position += 1
+
         for  i in range(ntiles):
             tile = self.tiles[i]
             if tile.size[0] != self.tile_width:
@@ -167,8 +155,3 @@ class Timeline(Audio):
 
     def done(self):
         self.mainloop.quit()
-
-    def onBusMessage(self, bus, message):
-        if message.src == self and message.type == gst.MESSAGE_EOS:
-            self.done()
-