I try to run python program in which I want scan number plate using web camera of my laptop but I get this error when I try to run it. I use OpenALPR and OpenCV for this.
I am attaching a screenshot of errors.
image of error:
Here below is the link to the code of the program.
import json, shlex, subprocess
class PlateReader:
def __init__(self):
#webcam subprocess args
webcam_command = "fswebcam -r 640x480 -S 20 --no-banner --quiet alpr.jpg"
self.webcam_command_args = shlex.split(webcam_command)
#alpr subprocess args
alpr_command = "alpr -c eu -t hr -n 300 -j alpr.jpg"
self.alpr_command_args = shlex.split(alpr_command)
def webcam_subprocess(self):
return subprocess.Popen(self.webcam_command_args, stdout=subprocess.PIPE)
def alpr_subprocess(self):
return subprocess.Popen(self.alpr_command_args, stdout=subprocess.PIPE)
def alpr_json_results(self):
self.webcam_subprocess().communicate()
alpr_out, alpr_error = self.alpr_subprocess().communicate()
if not alpr_error is None:
return None, alpr_error
elif "No license plates found." in alpr_out:
return None, None
try:
return json.loads(alpr_out), None
except ValueError, e:
return None, e
def read_plate(self):
alpr_json, alpr_error = self.alpr_json_results()
if not alpr_error is None:
print alpr_error
return
if alpr_json is None:
print "No results!"
return
results = alpr_json["results"]
ordinal = 0
for result in results:
candidates = result["candidates"]
for candidate in candidates:
if candidate["matches_template"] == 1:
ordinal += 1
print "Guess {0:d}: {1:s} {2:.2f}%".format(ordinal, candidate["plate"], candidate["confidence"])
if __name__=="__main__":
plate_reader = PlateReader()
plate_reader.read_plate()
(ps-I tried tons of time to solve this code indention of StackOverflow, but I can't)
I'm used similar code too. Just remove from alpr_command = "alpr -c eu -t hr -n 300 -j alpr.jpg"
this atribute -t hr
. And this code should works.
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