import sigrokdecode as srd
+class SamplerateError(Exception):
+ pass
+
class Decoder(srd.Decoder):
- api_version = 1
+ api_version = 2
id = 'guess_bitrate'
name = 'Guess bitrate'
longname = 'Guess bitrate/baudrate'
def putx(self, data):
self.put(self.ss_edge, self.samplenum, self.out_ann, data)
- def __init__(self, **kwargs):
+ def __init__(self):
self.olddata = None
self.ss_edge = None
self.first_transition = True
def metadata(self, key, value):
if key == srd.SRD_CONF_SAMPLERATE:
- self.samplerate = value;
+ self.samplerate = value
def decode(self, ss, es, data):
- if self.samplerate is None:
- raise Exception("Cannot decode without samplerate.")
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
for (self.samplenum, pins) in data:
data = pins[0]
continue
# Initialize first self.olddata with the first sample value.
- if self.olddata == None:
+ if self.olddata is None:
self.olddata = data
continue
# Get the smallest distance between two transitions
# and use that to calculate the bitrate/baudrate.
- if self.first_transition == True:
+ if self.first_transition:
self.ss_edge = self.samplenum
self.first_transition = False
else:
b = self.samplenum - self.ss_edge
- if self.bitwidth == None or b < self.bitwidth:
+ if self.bitwidth is None or b < self.bitwidth:
self.bitwidth = b
bitrate = int(float(self.samplerate) / float(b))
self.putx([0, ['%d' % bitrate]])
self.ss_edge = self.samplenum
self.olddata = data
-