+ cd_count = None
+ if self.options['cd_freq']:
+ cd_count = int(self.samplerate / self.options['cd_freq']) + 1
+ prev_ir = None
+
+ while True:
+ # Detect changes in the presence of an active input signal.
+ # The decoder can either be fed an already filtered RX signal
+ # or optionally can detect the presence of a carrier. Periods
+ # of inactivity (signal changes slower than the carrier freq,
+ # if specified) pass on the most recently sampled level. This
+ # approach works for filtered and unfiltered input alike, and
+ # only slightly extends the active phase of input signals with
+ # carriers included by one period of the carrier frequency.
+ # IR based communication protocols can cope with this slight
+ # inaccuracy just fine by design. Enabling carrier detection
+ # on already filtered signals will keep the length of their
+ # active period, but will shift their signal changes by one
+ # carrier period before they get passed to decoding logic.
+ if cd_count:
+ (cur_ir,) = self.wait([{0: 'e'}, {'skip': cd_count}])
+ if self.matched[0]:
+ cur_ir = self.active
+ if cur_ir == prev_ir:
+ continue
+ prev_ir = cur_ir
+ self.ir = cur_ir
+ else:
+ (self.ir,) = self.wait({0: 'e'})
+