[pitivi] previewers: Rename cleanup method

[Alexandru Băluț <alexbalut src gnome org>]

commit 5a49345894a546e349d1740b316d9faa89c8509d
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Mon Nov 7 11:54:47 2016 +0100

    previewers: Rename cleanup method
    
    Reviewed-by: Thibault Saunier <tsaunier gnome org>
    Differential Revision: https://phabricator.freedesktop.org/D1452

 pitivi/timeline/elements.py   |    2 +-
 pitivi/timeline/previewers.py |    6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/pitivi/timeline/elements.py b/pitivi/timeline/elements.py
index 7a82a4b..a00242b 100644
--- a/pitivi/timeline/elements.py
+++ b/pitivi/timeline/elements.py
@@ -446,7 +446,7 @@ class TimelineElement(Gtk.Layout, Zoomable, Loggable):
 
     def release(self):
         if self.__previewer:
-            self.__previewer.cleanup()
+            self.__previewer.release()
 
     # Public API
     def setSize(self, width, height):
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 23bf0ad..1d87225 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -54,7 +54,7 @@ except ImportError:
 
 
 WAVEFORMS_CPU_USAGE = 30
-SAMPLE_DURATION = 10000000
+SAMPLE_DURATION = Gst.SECOND / 100
 
 # A little lower as it's more fluctuating
 THUMBNAILS_CPU_USAGE = 20
@@ -693,7 +693,7 @@ class VideoPreviewer(Previewer, Zoomable, Loggable):
             self.pipeline = None
         self.emit("done")
 
-    def cleanup(self):
+    def release(self):
         """Stops preview generation and cleans the object."""
         self.stopGeneration()
         Zoomable.__del__(self)
@@ -1161,7 +1161,7 @@ class AudioPreviewer(Previewer, Zoomable, Loggable):
 
         self.emit("done")
 
-    def cleanup(self):
+    def release(self):
         """Stops preview generation and cleans the object."""
         self.stopGeneration()
         Zoomable.__del__(self)