Source Code for Module flumotion.component.effects.colorbalance.colorbalance

  1  # -*- Mode: Python -*- 
  2  # vi:si:et:sw=4:sts=4:ts=4 
  3  # 
  4  # Flumotion - a streaming media server 
  5  # Copyright (C) 2004,2005,2006,2007 Fluendo, S.L. (www.fluendo.com). 
  6  # All rights reserved. 
  7   
  8  # This file may be distributed and/or modified under the terms of 
  9  # the GNU General Public License version 2 as published by 
 10  # the Free Software Foundation. 
 11  # This file is distributed without any warranty; without even the implied 
 12  # warranty of merchantability or fitness for a particular purpose. 
 13  # See "LICENSE.GPL" in the source distribution for more information. 
 14   
 15  # Licensees having purchased or holding a valid Flumotion Advanced 
 16  # Streaming Server license may use this file in accordance with the 
 17  # Flumotion Advanced Streaming Server Commercial License Agreement. 
 18  # See "LICENSE.Flumotion" in the source distribution for more information. 
 19   
 20  # Headers in this file shall remain intact. 
 21   
 22  import gst 
 23  import gst.interfaces 
 24   
 25  from flumotion.component import feedcomponent 
 26   
 27  __version__ = "$Rev: 6125 $" 
 28   
 29   
 30 -class Colorbalance(feedcomponent.Effect): 
 31      logCategory = "colorbalance" 
 32   
 33 -    def __init__(self, name, element, hue, saturation, brightness, contrast, 
 34          pipeline=None): 
 35          """ 
 36          @param element: the GStreamer element supporting the colorbalance 
 37                          interface 
 38          @param hue: the colorbalance hue, as a percentage 
 39          @type  hue: float 
 40          @param saturation: the colorbalance saturation, as a percentage 
 41          @type saturation: float 
 42          @param brightness: the colorbalance brightness, as a percentage 
 43          @type brightness: float 
 44          @param contrast: the colorbalance contrast, as a percentage 
 45          @type contrast: float 
 46          @param pipeline: the pipeline 
 47          @type pipeline: L{gst.Pipeline} 
 48          """ 
 49          self.debug("colorbalance init") 
 50          feedcomponent.Effect.__init__(self, name) 
 51          self._element = element 
 52          if pipeline: 
 53              bus = pipeline.get_bus() 
 54              bus.connect('message::state-changed', 
 55                  self._bus_message_received_cb, 
 56                  hue, saturation, brightness, contrast) 
 57   
 58          self._channels = None 
 59   
 60 -    def setUIState(self, state): 
 61          feedcomponent.Effect.setUIState(self, state) 
 62          if state: 
 63              for k in 'Hue', 'Saturation', 'Brightness', 'Contrast': 
 64                  state.addKey('colorbalance-%s' % k, 0.0) 
 65   
 66      # State change handling for 0.10 
 67 -    def _bus_message_received_cb(self, bus, message, hue, saturation, 
 68          brightness, contrast): 
 69          """ 
 70          @param bus: the message bus sending the message 
 71          @param message: the message received 
 72          """ 
 73          t = message.type 
 74          if t == gst.MESSAGE_STATE_CHANGED and message.src == self._element: 
 75              (old, new, pending) = message.parse_state_changed() 
 76              # we have a state change 
 77              if old == gst.STATE_READY and new == gst.STATE_PAUSED: 
 78                  self._setInitialColorBalance(hue, 
 79                      saturation, brightness, contrast) 
 80   
 81 -    def effect_setColorBalanceProperty(self, which, value): 
 82          """ 
 83          Set a color balance property. 
 84   
 85          @param which: which property to change 
 86          @param value: what value to set it to (float between 0.0 and 100.0) 
 87   
 88          Returns: the actual percentage it was set to 
 89          """ 
 90          if not self._channels: 
 91              return value 
 92   
 93          for i in self._channels: 
 94              if i.label == which: 
 95                  if value: 
 96                      device_value = _percent_to_value(value, 
 97                          i.min_value, i.max_value) 
 98                      self.debug("setting percentage: %.1f, " 
 99                                 "value %d <= %d <= %d", 
100                                 value, i.min_value, device_value, 
101                                 i.max_value) 
102                      self._element.set_value(i, device_value) 
103                  device_value = self._element.get_value(i) 
104                  percent = _value_to_percent(device_value, 
105                      i.min_value, i.max_value) 
106                  self.debug('device says %s=%.1f', i.label, percent) 
107                  # notify all others too 
108                  if not self.uiState: 
109                      self.warning("effect %s doesn't have a uiState" % 
110                          self.name) 
111                  else: 
112                      self.uiState.set('colorbalance-%s' % which, percent) 
113                  return percent 
114   
115          # didn't find it 
116          return value 
117   
118 -    def _setInitialColorBalance(self, hue, saturation, brightness, contrast): 
119          self._channels = self._element.list_colorbalance_channels() 
120          self.debug('colorbalance channels: %d' % len(self._channels)) 
121          self.effect_setColorBalanceProperty('Hue', hue) 
122          self.effect_setColorBalanceProperty('Saturation', saturation) 
123          self.effect_setColorBalanceProperty('Brightness', brightness) 
124          self.effect_setColorBalanceProperty('Contrast', contrast) 
125   
126 -def _value_to_percent(value, min, max): 
127      """ 
128      Convert an integer value between min and max to a percentage. 
129      """ 
130      return float(value - min) / float(max - min) * 100.0 
131   
132 -def _percent_to_value(percentage, min, max): 
133      """ 
134      Convert an percentage value to an integer value between min and max. 
135      """ 
136      return int(min + percentage / 100.0 * (max - min)) 
137