improvement in slicing data? - python-3.x

BACKGROUND
I have a piece of hardware that returns an ascii stream & the user can choose
the number of timesteps
the number of channels
One packet = [ADDRESS][MSB][LSB][CHECKSUM]
One timestamp = [TIME_PACKET][CH1_PACKET][CH2_PACKET][CH3_PACKET][CH4_PACKET][CH5_PACKET][CH6_PACKET][CH7_PACKET]
Below is some stripped down code that I use to create 7 plus time arrays to then plot via matplotlib. The issue is, it takes a fair amount of time to process... 2.7seconds for 30,000 samples & 7 channels. I have used cython and I compiled this block down as a C extension and it isn't that much faster...
COMPLETE time is 2.7seconds.
Disable Checksum is 1.8seconds # this one test is 0.9seconds
Disable sign extend is 1.8seconds # this one test is 0.9 seconds
Disable all checks is 1.0 seconds
so roughly half the time is splitting the data
1/4 of the time is Checksum check on each packet
1/4 of the time is sign extend check on each packet
those checks are quite important as they help identify framing errors w.r.t. the USB link & also any noise pickup on the piece of test equipment (so the top 4bits then start being incorrectly set...)
Is the below code reasonably efficient and should I live with it or is it really really bad...
import numpy as np
import time
BIT_LENGTH=16 # payload bitlength
num_samples=30000 # number of samples
packet = 4 # 4 bytes
chT = b'\x01\x00\x05\xfb' # timestep of 5 # 1
ch1 = b'\x03\x00\x11\xed' # data 17 # 3
ch2 = b'\x04\x00\x07\xfc' # data 7 # 4
ch3 = b'\x08\x00\x17\xe0' # data 23 # 8
ch4 = b'\x0c\x00e\x96' # data 101 # 12
ch5 = b'\x0e\x00\x01\xf0' # data 1 # 14
ch6 = b'\x13\x04\x00\xe8' # data 1024 # 19
ch7 = b'\x14\x04\xd2=' # data 1234 # 20
stream = chT+ch1+ch2+ch3+ch4+ch5+ch6+ch7
stream = stream*num_samples
req = [1,3,4,8,12,14,19,20] # array of channel addresses.
req_array = [np.zeros(num_samples) for i in req] # init np arrays.
fpga_error_codes = {
'\x80\x00\x01':'ERR 1',
'\x80\x00\x02':'ERR 2',
'\x80\x00\x04':'ERR 3',
'\x80\x00\x08':'ERR 4',
'\x80\x00\x10':'ERR 5',
'\x80\x00\x20':'ERR 6',
'\x80\x00\x40':'ERR 7',
}
class PacketError(Exception):
def __init__(self, value):
self.parameter = value
def __str__(self):
return repr(self.parameter)
### FUNCTIONS USED
def checksum(data):
return (~(data[0] ^ data[1] ^ data[2]) & 0xff).to_bytes(1,byteorder='big',signed=False)
def check_packet_bits(data, s=None, nbits=BIT_LENGTH):
''' additional method to assist with error detection'''
int_data = int.from_bytes(data[1:-1],byteorder='big',signed=True)
if s=='unsigned':
if int_data > (2**nbits)-1:
return True # ERROR!
else:
return False
elif s == 'signed':
hi = 2**(nbits -1) -1
lo = -1 * 2**(nbits-1)
return True if int_data < lo else True if int_data > hi else False
def check_packet(addr, data, num_bits=BIT_LENGTH, sign_type='signed'):
'''Method to determine whether an ITI packet is valid'''
if checksum(data[:-1]) != data[-1].to_bytes(1,byteorder='big',signed=False):
msg = 'Checksum Error: %s' % ( ' '.join([hex(i) for i in data]) )
raise PacketError(msg)
elif data[0] == '\x80':
msg = "%sd %s" %(fpga_error_codes.get(data[:3],'Unspecified Error'),' '.join([hex(i) for i in data]) )
raise PacketError(msg)
elif data[0] != addr:
msg = "Wrong addr. Got: %d Want: %d %s" % (data[0],addr,' '.join([hex(i) for i in data]) )
raise PacketError(msg)
elif check_packet_bits(data,s=sign_type, nbits=num_bits):
msg = "Target FPGA sent a corrupted payload addr: %d, page: %d Data: 0x%02x%02x" %(addr, self.present_page,data[1],data[2])
raise PacketError(msg)
else:
return int.from_bytes(data[1:-1],byteorder='big',signed=True)
t0= time.time()
### CODE IN QUESTION
timestep_iter = zip(*(iter(stream),)*packet*len(req))
for entry,time_window in enumerate(timestep_iter):
packet_iter = zip(*(iter(bytes(time_window)),)*packet)
tmp = [check_packet(i,bytes(next(packet_iter)),sign_type=['signed','unsigned'][0],num_bits=12,) for i in req]
for index,addr in enumerate(req):
req_array[index][entry] = tmp[index]
req_array[0] = req_array[0].cumsum() - req_array[0]
### CODE IN QUESTION
print(time.time()-t0)

Related

Pitch and Yaw from a Wiimote Motion Plus using Cwiid Python

I'm trying to extract the orientation of a wiimote using cwiid in python. I've managed to get the accelerometer values but there doesn't seem to be any object attributes relating to the purely gyroscopic data.
This guy managed to do it in python, but to the best of my knowledge there's no python code online with an example.
https://www.youtube.com/watch?v=cUjh0xQO6eY
There is information on wiibrew about the controller data but again this seems to be excluded from any python library.
Has anyone got any suggestions? This link has an example of getting gyro data but the packages used don't seem available.
I was actually looking for this a few days ago, found this post: https://ofalcao.pt/blog/2014/controlling-the-sbrick-with-a-wiimote. More specifically, I think the code you're looking for is:
# roll = accelerometer[0], standby ~125
# pitch = accelerometer[1], standby ~125
...
roll=(wm.state['acc'][0]-125)
pitch=(wm.state['acc'][1]-125)
I'm assuming you can use the z-axis (index 2) for the yaw
So this question has a few parts, firstly how to extract the gyro data from the motion plus sensor. To do this, the motion plus will first need to be enabled.
The gyro provides the angular rotation vectors, but due to drift caused by integration errors you can't simply use a combination of these two things to get Eular angles. The second part of the question is how to use this data to give position, and that is done by using a Kalman filter, a highly complex matrix sequence, or a complementary filter, a less complex mathematical operation. Both of these filters are essentially combining the gyro and accelerometer data, so as mentioned in a comment above, resulting in more stable measurements, less drift and a system not prone to breaking when the remote is shaken.
Kalman filter:
http://blog.tkjelectronics.dk/2012/09/a-practical-approach-to-kalman-filter-and-how-to-implement-it/
Using PyKalman on Raw Acceleration Data to Calculate Position
Complementary filter
https://www.instructables.com/Angle-measurement-using-gyro-accelerometer-and-Ar/
Still currently developing the core but will post when I'm finished, hopefully tomorrow.
The foundation code I am using to test the measurements is found here:
http://andrew-j-norman.blogspot.com/2010/12/more-code.html. Very handy, as it plots the sensor readings automatically after recording. You can see by doing this that even when still, the position estimate by using simple integration of the angular velocities results in a drift in the position vector.
EDIT:
Testing this allows for the gyro sensor to accurately calculate the angle changed over time, however there remains drift in the acceleration - which I believe is unavoidable.
Here is an image demonstrating the gyro motion sensor:
Just finished up the code:
#!/usr/bin/python
import cwiid
from time import time, asctime, sleep, perf_counter
from numpy import *
from pylab import *
import math
import numpy as np
from operator import add
HPF = 0.98
LPF = 0.02
def calibrate(wiimote):
print("Keep the remote still")
sleep(3)
print("Calibrating")
messages = wiimote.get_mesg()
i=0
accel_init = []
angle_init = []
while (i<1000):
sleep(0.01)
messages = wiimote.get_mesg()
for mesg in messages:
# Motion plus:
if mesg[0] == cwiid.MESG_MOTIONPLUS:
if record:
angle_init.append(mesg[1]['angle_rate'])
# Accelerometer:
elif mesg[0] == cwiid.MESG_ACC:
if record:
accel_init.append(list(mesg[1]))
i+=1
accel_init_avg = list(np.mean(np.array(accel_init), axis=0))
print(accel_init_avg)
angle_init_avg = sum(angle_init)/len(angle_init)
print("Finished Calibrating")
return (accel_init_avg, angle_init_avg)
def plotter(plot_title, timevector, data, position, n_graphs):
subplot(n_graphs, 1, position)
plot(timevector, data[0], "r",
timevector, data[1], "g",
timevector, data[2], "b")
xlabel("time (s)")
ylabel(plot_title)
print("Press 1+2 on the Wiimote now")
wiimote = cwiid.Wiimote()
# Rumble to indicate a connection
wiimote.rumble = 1
print("Connection established - release buttons")
sleep(0.2)
wiimote.rumble = 0
sleep(1.0)
wiimote.enable(cwiid.FLAG_MESG_IFC | cwiid.FLAG_MOTIONPLUS)
wiimote.rpt_mode = cwiid.RPT_BTN | cwiid.RPT_ACC | cwiid.RPT_MOTIONPLUS
accel_init, angle_init = calibrate(wiimote)
str = ""
print("Press plus to start recording, minus to end recording")
loop = True
record = False
accel_data = []
angle_data = []
messages = wiimote.get_mesg()
while (loop):
sleep(0.01)
messages = wiimote.get_mesg()
for mesg in messages:
# Motion plus:
if mesg[0] == cwiid.MESG_MOTIONPLUS:
if record:
angle_data.append({"Time" : perf_counter(), \
"Rate" : mesg[1]['angle_rate']})
# Accelerometer:
elif mesg[0] == cwiid.MESG_ACC:
if record:
accel_data.append({"Time" : perf_counter(), "Acc" : [mesg[1][i] - accel_init[i] for i in range(len(accel_init))]})
# Button:
elif mesg[0] == cwiid.MESG_BTN:
if mesg[1] & cwiid.BTN_PLUS and not record:
print("Recording - press minus button to stop")
record = True
start_time = perf_counter()
if mesg[1] & cwiid.BTN_MINUS and record:
if len(accel_data) == 0:
print("No data recorded")
else:
print("End recording")
print("{0} data points in {1} seconds".format(
len(accel_data), perf_counter() - accel_data[0]["Time"]))
record = False
loop = False
else:
pass
wiimote.disable(cwiid.FLAG_MESG_IFC | cwiid.FLAG_MOTIONPLUS)
if len(accel_data) == 0:
sys.exit()
timevector = []
a = [[],[],[]]
v = [[],[],[]]
p = [[],[],[]]
last_time = 0
velocity = [0,0,0]
position = [0,0,0]
for n, x in enumerate(accel_data):
if (n == 0):
origin = x
else:
elapsed = x["Time"] - origin["Time"]
delta_t = x["Time"] - last_time
timevector.append(elapsed)
for i in range(3):
acceleration = x["Acc"][i] - origin["Acc"][i]
velocity[i] = velocity[i] + delta_t * acceleration
position[i] = position[i] + delta_t * velocity[i]
a[i].append(acceleration)
v[i].append(velocity[i])
p[i].append(position[i])
last_time = x["Time"]
n_graphs = 3
if len(angle_data) == len(accel_data):
n_graphs = 5
angle_accel = [(math.pi)/2 if (j**2 + k**2)==0 else math.atan(i/math.sqrt(j**2 + k**2)) for i,j,k in zip(a[0],a[1],a[2])]
ar = [[],[],[]] # Angle rates
aa = [[],[],[]] # Angles
angle = [0,0,0]
for n, x in enumerate(angle_data):
if (n == 0):
origin = x
else:
delta_t = x["Time"] - last_time
for i in range(3):
rate = x["Rate"][i] - origin["Rate"][i]
angle[i] = HPF*(np.array(angle[i]) + delta_t * rate) + LPF*np.array(angle_accel)
ar[i].append(rate)
aa[i].append(angle[i])
last_time = x["Time"]
plotter("Acceleration", timevector, a, 1, n_graphs)
if n_graphs == 5:
plotter("Angle Rate", timevector, ar, 4, n_graphs)
plotter("Angle", timevector, aa, 5, n_graphs)
show()

MST challenge gives "time exceeded" error [closed]

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Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
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I am doing the BLINNET problem on Sphere Online Judge where I need to find the cost of a minimum spanning tree. I should follow a structure with Edge and Vertex instances. Vertices represent cities in this case.
I get a "time exceeded" error, and I feel like too many for loop iterations are at the cause, but that is the best I can do. I want to try the binary sort to see if it works with that, but that is not easy as it should be sorted using the key property in the City class.
Sample input
2
4
gdansk
2
2 1
3 3
bydgoszcz
3
1 1
3 1
4 4
torun
3
1 3
2 1
4 1
warszawa
2
2 4
3 1
3
ixowo
2
2 1
3 3
iyekowo
2
1 1
3 7
zetowo
2
1 3
2 7
Output for the Sample
3
4
My code
import sys
import heapq
class City:
def __init__(self, city_id):
self.city_id = city_id
self.key = float('inf')
self.parent = None
self.edge_list = list()
self.visited = False
#self.city_name = None
def is_not_visited(self):
if self.visited is False:
return True
return False
def add_neighbor(self, edge):
self.edge_list.append(edge)
def __lt__(self, other):
return self.key < other.key
class Edge:
def __init__(self, to_vertex, cost):
self.to_vertex = to_vertex
self.cost = cost
#
# def find_and_pop(queue):
# min = queue[0]
# index = 0
# for a in range(0, len(queue)):
# if queue[a].key < min.key:
# min = queue[a]
# index = a
# return queue.pop(index)
#
def MST(vertices_list):
queue = vertices_list
current = queue[0]
current.key = 0
#visited_list = list()
#heapq.heapify(queue)
total_weight = 0
while queue:
#current = find_and_pop(queue)
current = queue.pop(0)
for edge in current.edge_list:
if edge.to_vertex.is_not_visited():
if edge.cost < edge.to_vertex.key:
edge.to_vertex.key = edge.cost
edge.to_vertex.parent = current
total_weight = total_weight + current.key
current.visited = True
queue = sorted(queue, key=lambda x: x.city_id)
#heapq.heapify(queue)
#visited_list.append(current)
# total_weight = 0
# for x in visited_list:
# total_weight = total_weight + x.key
sys.stdout.write("{0}\n".format(total_weight))
class TestCase:
def __init__(self, vertices):
self.vertices = vertices
testcases = []
def main():
case_num = int(sys.stdin.readline())
#skip_line = sys.stdin.readline()
for n_case in range(0, case_num):
sys.stdin.readline()
vertices_list = list()
number_of_city = int(sys.stdin.readline())
#interate and make for the time of number of cities
for n_city in range(0, number_of_city):
city = City(n_city)
vertices_list.append(city)
for n_city in range(0, number_of_city):
c_name = sys.stdin.readline()
#vertices_list[n_city].city_name = c_name
num_neighbor = int(sys.stdin.readline())
for n_neigh in range(0, num_neighbor):
to_city_cost = sys.stdin.readline()
to_city_cost = to_city_cost.split(" ")
to_city = int(to_city_cost[0])
cost = int(to_city_cost[1])
edge = Edge(vertices_list[to_city-1], cost)
vertices_list[n_city].edge_list.append(edge)
testcase = TestCase(vertices_list)
testcases.append(testcase)
count = 0
for testcase in testcases:
MST(testcase.vertices)
# if count < case_num -1:
# print()
# count = count + 1
if __name__ == "__main__":
main()
The sorted call in your MST loop makes the solution inefficient. You have some commented-out code that relies on heapq, and that is indeed the way to avoid having to sort the queue each time you alter it. Anyway, I don't understand why you would sort the queue by city id. If anything, it should be sorted by key.
Although it could work with the key property as you did it, it seems more natural to me to add edges to the queue (heap) instead of vertices, so you have the edge cost as the basis for the heap property. Also, that queue should not have all the items from the start, but add them as they are selected during the algorithm. And, that corresponds more the the MST-building algorithm, which adds edge after edge, each time the one with the minimum cost.
If edges are pushed on a heap, they must be comparable. So __lt__ must be implemented on the Edge class like you did for the Vertex class.
class Edge:
# ... your code remains unchanged... Just add:
def __lt__(self, other):
return self.cost < other.cost
def MST(vertices_list):
# first edge in the queue is a virtual one with zero cost.
queue = [Edge(vertices_list[0], 0)] # heap of edges, ordered by cost
total_weight = 0
while queue:
mst_edge = heapq.heappop(queue) # pop both cost & vertex
current = mst_edge.to_vertex
if current.visited: continue
for edge in current.edge_list:
if not edge.to_vertex.visited:
heapq.heappush(queue, edge)
current.visited = True
total_weight += mst_edge.cost
sys.stdout.write("{0}\n".format(total_weight))

Exporting a cellular automaton data to csv in Python

I've been working in Reaction-Diffusion cellular automata with the cellpylib library for a course in my university (I wrote it all in one script so you don't have to install/download anything). I'd like to save the evolution of the automata data to a csv file to run some statistics. That is, I'd like to save the data in columns where the first column is 'number of "1"' and the second column: 'time steps'.
Thus, I need help in:
(1) Creating a variable that saves the amount of '1' per time step (I think so).
(2) I need to export all that data to a csv file (number of "1" and the corresponding iteration, from 1 to time_steps in the code below).
The code is the following.
#Libraries
import matplotlib
matplotlib.matplotlib_fname()
import matplotlib.pyplot as plt
import matplotlib as mpl
import matplotlib.animation as animation
import numpy as np
import csv
# Conditions
#############################
theta = 1 # this is the condition for Moore neighbourhood
Int = 100 # this is the iteration speed (just for visualization)
time_steps = 100 # Iterations
size = 8 # this is the size of the matrix (8x8)
#############################
# Definitions
def plot2d_animate(ca, title=''):
c = mpl.colors.ListedColormap(['green', 'red', 'black', 'gray'])
n = mpl.colors.Normalize(vmin=0,vmax=3)
fig = plt.figure()
plt.title(title)
im = plt.imshow(ca[0], animated=True, cmap=c, norm=n)
i = {'index': 0}
def updatefig(*args):
i['index'] += 1
if i['index'] == len(ca):
i['index'] = 0
im.set_array(ca[i['index']])
return im,
ani = animation.FuncAnimation(fig, updatefig, interval=Int, blit=True)
plt.show()
def init_simple2d(rows, cols, val=1, dtype=np.int):
x = np.zeros((rows, cols), dtype=dtype)
x[x.shape[0]//2][x.shape[1]//2] = val
return np.array([x])
def evolve2d(cellular_automaton, timesteps, apply_rule, r=1, neighbourhood='Moore'):
_, rows, cols = cellular_automaton.shape
array = np.zeros((timesteps, rows, cols), dtype=cellular_automaton.dtype)
array[0] = cellular_automaton
von_neumann_mask = np.zeros((2*r + 1, 2*r + 1), dtype=bool)
for i in range(len(von_neumann_mask)):
mask_size = np.absolute(r - i)
von_neumann_mask[i][:mask_size] = 1
if mask_size != 0:
von_neumann_mask[i][-mask_size:] = 1
def get_neighbourhood(cell_layer, row, col):
row_indices = [0]*(2*r+1)
for i in range(-r,r+1):
row_indices[i+r]=(i+row) % cell_layer.shape[0]
col_indices = [0]*(2*r+1)
for i in range(-r,r+1):
col_indices[i+r]=(i+col) % cell_layer.shape[1]
n = cell_layer[np.ix_(row_indices, col_indices)]
if neighbourhood == 'Moore':
return n
elif neighbourhood == 'von Neumann':
return np.ma.masked_array(n, von_neumann_mask)
else:
raise Exception("unknown neighbourhood type: %s" % neighbourhood)
for t in range(1, timesteps):
cell_layer = array[t - 1]
for row, cell_row in enumerate(cell_layer):
for col, cell in enumerate(cell_row):
n = get_neighbourhood(cell_layer, row, col)
array[t][row][col] = apply_rule(n, (row, col), t)
return array
def ca_reaction_diffusion(neighbourhood, c, t):
center_cell = neighbourhood[1][1]
total = np.sum(neighbourhood==1)
if total >= theta and center_cell==0:
return 1
elif center_cell == 1:
return 2
elif center_cell == 2:
return 3
elif center_cell == 3:
return 0
else:
return 0
# Initial condition
cellular_automaton = init_simple2d(size, size, val=0, dtype=int)
# Excitable initial cells
cellular_automaton[:, [1,2], [1,1]] = 1
# The evolution
cellular_automaton = evolve2d(cellular_automaton,
timesteps=time_steps,
neighbourhood='Moore',
apply_rule=ca_reaction_diffusion)
animation=plot2d_animate(cellular_automaton)
Explanation of the code:
As you can see, there are 4 states: 0 (green), 1 (red), 2 (black) and 3 (gray). The way the automata evolves is with the cellular_automaton conditions. That is, for example, if a center cell has a value of 0 (excitable cell) and at least one cell (theta value) on its Moore neighbourhood is in state 1, in the following time step the same cell will be at state 1 (excited).
To notice:
The configuration of this matrix is toroidal, and the definitions are taken from the cellpylib library.
I've been stuck with this for over a week, so I'd really appreciate some help. Thanks in advance!
I am not well-experienced in this subject matter (and I was not fully clear on what you intended for me to do). I went through and implemented the counting of the specific "0", "1", "2" and "3" value cells in "evolve2d" function. This code should be viewed as "starter code"; whatever specifically you are trying to do should piggyback off of what I have given you. Additionally, this task could have been accomplished through some better code design and definitely, better planning of your function locations (as part of better coding practice and overall cleaner code that is easy to debug). Please peruse and UNDERSTAND the changes that I made.
#Libraries
import matplotlib
matplotlib.matplotlib_fname()
import matplotlib.pyplot as plt
import matplotlib as mpl
import matplotlib.animation as animation
import numpy as np
import csv
# Conditions
#############################
theta = 1 # this is the condition for Moore neighbourhood
iter_speed = 100 # this is the iteration speed (just for visualization)
time_steps = 100 # Iterations
size = 8 # this is the size of the matrix (8x8)
#############################
# Definitions
def plot2d_animate(ca, title=''):
c = mpl.colors.ListedColormap(['green', 'red', 'black', 'gray'])
n = mpl.colors.Normalize(vmin=0,vmax=3)
fig = plt.figure()
plt.title(title)
im = plt.imshow(ca[0], animated=True, cmap=c, norm=n)
i = {'index': 0}
def updatefig(*args):
i['index'] += 1
if i['index'] == len(ca):
i['index'] = 0
im.set_array(ca[i['index']])
return im,
ani = animation.FuncAnimation(fig, updatefig, interval=iter_speed, blit=True)
plt.show()
#############I ADDED EXTRA ARGUMENTs FOR THE FUNCTION BELOW
def get_neighbourhood(cell_layer, row, col, r = 1, neighbourhood = "Moore"):
row_indices = [0]*(2*r+1)
for i in range(-r,r+1):
row_indices[i+r]=(i+row) % cell_layer.shape[0]
col_indices = [0]*(2*r+1)
for i in range(-r,r+1):
col_indices[i+r]=(i+col) % cell_layer.shape[1]
n = cell_layer[np.ix_(row_indices, col_indices)]
if neighbourhood == 'Moore':
return n
elif neighbourhood == 'von Neumann':
return np.ma.masked_array(n, von_neumann_mask)
else:
raise Exception("unknown neighbourhood type: %s" % neighbourhood)
def init_simple2d(rows, cols, val=1, dtype=np.int):
x = np.zeros((rows, cols), dtype=dtype)
x[x.shape[0]//2][x.shape[1]//2] = val
return np.array([x])
#Inner functions was moved due to bad coding practice. Arguments were also changed. Make sure you understand what I did.
def evolve2d(cellular_automaton, timesteps, apply_rule, r=1, neighbourhood='Moore'):
_, rows, cols = cellular_automaton.shape
array = np.zeros((timesteps, rows, cols), dtype=cellular_automaton.dtype)
array[0] = cellular_automaton
von_neumann_mask = np.zeros((2*r + 1, 2*r + 1), dtype=bool)
for i in range(len(von_neumann_mask)):
mask_size = np.absolute(r - i)
von_neumann_mask[i][:mask_size] = 1
if mask_size != 0:
von_neumann_mask[i][-mask_size:] = 1
#################################################
#These lists keep track of values over the course of the function:
Result_0 = ["Number of 0"]
Result_1 = ["Number of 1"]
Result_2 = ["Number of 2"]
Result_3 = ["Number of 3"]
#################################################
for t in range(1, timesteps):
#################################################
#This dictionary keeps track of values per timestep
value_iter_tracker = {0: 0, 1: 0, 2: 0, 3: 0 }
#################################################
cell_layer = array[t - 1]
for row, cell_row in enumerate(cell_layer):
for col, cell in enumerate(cell_row):
n = get_neighbourhood(cell_layer, row, col)
################################################
res = apply_rule(n, (row, col), t)
value_iter_tracker[res]+=1
array[t][row][col] = res
################################################
print(value_iter_tracker)
########################################################
#Now we need to add the results of the iteration dictionary to the corresponding
#lists in order to eventually export to the csv
Result_0.append(value_iter_tracker[0])
Result_1.append(value_iter_tracker[1])
Result_2.append(value_iter_tracker[2])
Result_3.append(value_iter_tracker[3])
########################################################
############################################################
#function call to export lists to a csv:
timesteps_result = list(range(1, timesteps))
timesteps_result = ["Time Step"] + timesteps_result
#If you don't understand what is going on here, put print statement and/or read docs
vals = zip(timesteps_result, Result_0, Result_1, Result_2, Result_3)
write_to_csv_file(list(vals))
############################################################
return array
################################################################################
#THIS CODE IS FROM:
#https://stackoverflow.com/questions/14037540/writing-a-python-list-of-lists-to-a-csv-file
import pandas as pd
def write_to_csv_file(data):
data = [list(x) for x in data]
my_df = pd.DataFrame(data)
my_df.to_csv('output1.csv', index=False, header=False)
################################################################################
def ca_reaction_diffusion(neighbourhood, c, t):
center_cell = neighbourhood[1][1]
total = np.sum(neighbourhood==1)
if total >= theta and center_cell==0:
return 1
elif center_cell == 1:
return 2
elif center_cell == 2:
return 3
elif center_cell == 3:
return 0
else:
return 0
# Initial condition
cellular_automaton = init_simple2d(size, size, val=0, dtype=int)
# Excitable initial cells
cellular_automaton[:, [1,2], [1,1]] = 1
# The evolution
cellular_automaton = evolve2d(cellular_automaton,
timesteps=time_steps,
neighbourhood='Moore',
apply_rule=ca_reaction_diffusion)
animation=plot2d_animate(cellular_automaton)
I have left comments that should clarify the changes that I made. Essentially, when you call the evolve2d function, a csv file called "output1.csv" is created with the timestep results. I used the pandas package to write the data into a csv but other methods could have been used as well. I will leave it to you to take advantage of the changes that I made for your use. Hope this helps.

How to shorten silence in audio file using ffmpeg?

I'm trying to shorten excess silence in audio recordings using ffmpeg (shorten them, not cutting silence out entirely). The current code I use:
ffmpeg -hide_banner -i file_name.m4a -af silenceremove=0:0:0:-1:0.7:-30dB file_name_short.m4a
is not working. It detects silence longer than 0.7 seconds and remove them completely, which is not what I want. Anyone knows how to truncate silence, say, to shorten silence longer than 1 second down to 0.5 second?
The parameters of ffmpeg's silenceremove command seem to only allow you to delete all of the silence that is above a certain length. This means if you pass in stop_duration=0.5, and there is a block of silence that is 2.2 seconds long, you'll end up with 0.2 seconds of silence remaining (2.2 - 0.5 - 0.5 - 0.5 - 0.5 = 0.2).
If you don't mind converting back and forth between .wav format, you can use this Python script that I cooked up. It has quite a few options and even though it's in Python, it's using NumPy, so it can handle short files in much less than a second, and can handle a 2 hour long .wav in about 5.7 seconds, which is decent. For serious speed, this could be rewritten in C++. For videos, it may be possible to expand the solution using OpenCV.
Pluses:
Can automatically determine threshold, with adjustable aggressiveness
Can specify the maximum silence duration
Can specify minimum non-silence duration to avoid momentary blips between silence
Can use it just to detect periods of silence (much faster; processes 2 hours in 1.7 seconds)
Avoids overwriting files unless told to do so
It's limited by the modules it uses. Catches are:
it reads the whole file into memory
it only works with wave files and doesn't keep the metadata. (see below for workaround)
it can handle the common WAVE standards, unless you don't have SciPy installed, in which case it uses Python's wave module which only works well with 16-bit PCM
Usage in your case:
Convert m4a to wav: ffmpeg -i myfile.m4a myfile.wav
Run Silence Remover: python3 trim_silence.py --input=myfile.wav
Convert back with metadata: ffmpeg -i result.wav -i myfile.m4a -map_metadata 1 myfile_trimmed.m4a
Full usage notes:
usage: trim_silence.py [-h] --input INPUT [--output OUTPUT] [--threshold THRESHOLD] [--silence-dur SILENCE_DUR] [--non-silence-dur NON_SILENCE_DUR]
[--mode MODE] [--auto-threshold] [--auto-aggressiveness AUTO_AGGRESSIVENESS] [--detect-only] [--verbose] [--show-silence] [--time-it]
[--overwrite]
optional arguments:
-h, --help show this help message and exit
--input INPUT (REQUIRED) name of input wav file (default: None)
--output OUTPUT name of output wave file (default: result.wav)
--threshold THRESHOLD
silence threshold - can be expressed in dB, e.g. --threshold=-25.5dB (default: -25dB)
--silence-dur SILENCE_DUR
maximum silence duration desired in output (default: 0.5)
--non-silence-dur NON_SILENCE_DUR
minimum non-silence duration between periods of silence of at least --silence-dur length (default: 0.1)
--mode MODE silence detection mode - can be 'any' or 'all' (default: all)
--auto-threshold automatically determine silence threshold (default: False)
--auto-aggressiveness AUTO_AGGRESSIVENESS
aggressiveness of the auto-threshold algorithm. Integer between [-20,20] (default: 3)
--detect-only don't trim, just detect periods of silence (default: False)
--verbose print general information to the screen (default: False)
--show-silence print locations of silence (always true if --detect-only is used) (default: False)
--time-it show steps and time to complete them (default: False)
--overwrite overwrite existing output file, if applicable (default: False)
Contents of trim_silence.py:
import numpy as np
import argparse
import time
import sys
import os
def testmode(mode):
mode = mode.lower()
valid_modes = ["all","any"]
if mode not in valid_modes:
raise Exception("mode '{mode}' is not valid - must be one of {valid_modes}")
return mode
def testaggr(aggr):
try:
aggr = min(20,max(-20,int(aggr)))
return aggr
except:
raise Exception("auto-aggressiveness '{aggr}' is not valid - see usage")
parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument("--input", type=str, help="(REQUIRED) name of input wav file", required=True)
parser.add_argument("--output", default="result.wav", type=str, help="name of output wave file")
parser.add_argument("--threshold", default="-25dB", type=str, help="silence threshold - can be expressed in dB, e.g. --threshold=-25.5dB")
parser.add_argument("--silence-dur", default=0.5, type=float, help="maximum silence duration desired in output")
parser.add_argument("--non-silence-dur", default=0.1, type=float, help="minimum non-silence duration between periods of silence of at least --silence-dur length")
parser.add_argument("--mode", default="all", type=testmode, help="silence detection mode - can be 'any' or 'all'")
parser.add_argument("--auto-threshold",action="store_true", help="automatically determine silence threshold")
parser.add_argument("--auto-aggressiveness",default=3,type=testaggr, help="aggressiveness of the auto-threshold algorithm. Integer between [-20,20]")
parser.add_argument("--detect-only", action="store_true", help="don't trim, just detect periods of silence")
parser.add_argument("--verbose", action="store_true", help="print general information to the screen")
parser.add_argument("--show-silence", action="store_true", help="print locations of silence (always true if --detect-only is used)")
parser.add_argument("--time-it", action="store_true", help="show steps and time to complete them")
parser.add_argument("--overwrite", action="store_true", help="overwrite existing output file, if applicable")
args = parser.parse_args()
args.show_silence = args.show_silence or args.detect_only
if not args.detect_only and not args.overwrite:
if os.path.isfile(args.output):
print(f"Output file ({args.output}) already exists. Use --overwrite to overwrite the existing file.")
sys.exit(1)
if (args.silence_dur < 0): raise Exception("Maximum silence duration must be >= 0.0")
if (args.non_silence_dur < 0): raise Exception("Minimum non-silence duration must be >= 0.0")
try:
from scipy.io import wavfile
using_scipy = True
except:
if args.verbose: print("Failure using 'import scipy.io.wavfile'. Using 'import wave' instead.")
import wave
using_scipy = False
if args.verbose: print(f"Inputs:\n Input File: {args.input}\n Output File: {args.output}\n Max. Silence Duration: {args.silence_dur}\n Min. Non-silence Duration: {args.non_silence_dur}")
from matplotlib import pyplot as plt
def plot(x):
plt.figure()
plt.plot(x,'o')
plt.show()
def threshold_for_channel(ch):
global data
nbins = 100
max_len = min(1024*1024*100,data.shape[0]) # limit to first 100 MiB
if len(data.shape) > 1:
x = np.abs(data[:max_len,ch]*1.0)
else:
x = np.abs(data[:max_len]*1.0)
if data.dtype==np.uint8: x -= 127
hist,edges = np.histogram(x,bins=nbins,density=True)
slope = np.abs(hist[1:] - hist[:-1])
argmax = np.argmax(slope < 0.00002)
argmax = max(0,min(argmax + args.auto_aggressiveness, len(edges)-1))
thresh = edges[argmax] + (127 if data.dtype==np.uint8 else 0)
return thresh
def auto_threshold():
global data
max_thresh = 0
channel_count = 1 if len(data.shape)==1 else data.shape[1]
for ch in range(channel_count):
max_thresh = max(max_thresh,threshold_for_channel(ch))
return max_thresh
silence_threshold = str(args.threshold).lower().strip()
if args.auto_threshold:
if args.verbose: print (f" Silence Threshold: AUTO (aggressiveness={args.auto_aggressiveness})")
else:
if "db" in silence_threshold:
silence_threshold_db = float(silence_threshold.replace("db",""))
silence_threshold = np.round(10**(silence_threshold_db/20.),6)
else:
silence_threshold = float(silence_threshold)
silence_threshold_db = 20*np.log10(silence_threshold)
if args.verbose: print (f" Silence Threshold: {silence_threshold} ({np.round(silence_threshold_db,2)} dB)")
if args.verbose: print (f" Silence Mode: {args.mode.upper()}")
if args.verbose: print("")
if args.time_it: print(f"Reading in data from {args.input}... ",end="",flush=True)
start = time.time()
if using_scipy:
sample_rate, data = wavfile.read(args.input)
input_dtype = data.dtype
Ts = 1./sample_rate
if args.auto_threshold:
silence_threshold = auto_threshold()
else:
if data.dtype != np.float32:
sampwidth = data.dtype.itemsize
if (data.dtype==np.uint8): silence_threshold += 0.5 # 8-bit unsigned PCM
scale_factor = (256**sampwidth)/2.
silence_threshold *= scale_factor
else:
handled_sampwidths = [2]
with wave.open(args.input,"rb") as wavin:
params = wavin.getparams()
if params.sampwidth in handled_sampwidths:
raw_data = wavin.readframes(params.nframes)
if params.sampwidth not in handled_sampwidths:
print(f"Unable to handle a sample width of {params.sampwidth}")
sys.exit(1)
end = time.time()
if args.time_it: print(f"complete (took {np.round(end-start,6)} seconds)")
if not using_scipy:
if args.time_it: print(f"Unpacking data... ",end="",flush=True)
start = time.time()
Ts = 1.0/params.framerate
if params.sampwidth==2: # 16-bit PCM
format_ = 'h'
data = np.frombuffer(raw_data,dtype=np.int16)
elif params.sampwidth==3: # 24-bit PCM
format_ = 'i'
print(len(raw_data))
data = np.frombuffer(raw_data,dtype=np.int32)
data = data.reshape(-1,params.nchannels) # reshape into channels
if args.auto_threshold:
silence_threshold = auto_threshold()
else:
scale_factor = (256**params.sampwidth)/2. # scale to [-1:1)
silence_threshold *= scale_factor
data = 1.0*data # convert to np.float64
end = time.time()
if args.time_it: print(f"complete (took {np.round(end-start,6)} seconds)")
silence_duration_samples = args.silence_dur / Ts
if args.verbose: print(f"Input File Duration = {np.round(data.shape[0]*Ts,6)}\n")
combined_channel_silences = None
def detect_silence_in_channels():
global combined_channel_silences
if len(data.shape) > 1:
if args.mode=="any":
combined_channel_silences = np.min(np.abs(data),axis=1) <= silence_threshold
else:
combined_channel_silences = np.max(np.abs(data),axis=1) <= silence_threshold
else:
combined_channel_silences = np.abs(data) <= silence_threshold
combined_channel_silences = np.pad(combined_channel_silences, pad_width=1,mode='constant',constant_values=0)
def get_silence_locations():
global combined_channel_silences
starts = combined_channel_silences[1:] & ~combined_channel_silences[0:-1]
ends = ~combined_channel_silences[1:] & combined_channel_silences[0:-1]
start_locs = np.nonzero(starts)[0]
end_locs = np.nonzero(ends)[0]
durations = end_locs - start_locs
long_durations = (durations > silence_duration_samples)
long_duration_indexes = np.nonzero(long_durations)[0]
if len(long_duration_indexes) > 1:
non_silence_gaps = start_locs[long_duration_indexes[1:]] - end_locs[long_duration_indexes[:-1]]
short_non_silence_gap_locs = np.nonzero(non_silence_gaps <= (args.non_silence_dur/Ts))[0]
for loc in short_non_silence_gap_locs:
if args.verbose and args.show_silence:
ns_gap_start = end_locs[long_duration_indexes[loc]] * Ts
ns_gap_end = start_locs[long_duration_indexes[loc+1]] * Ts
ns_gap_dur = ns_gap_end - ns_gap_start
print(f"Removing non-silence gap at {np.round(ns_gap_start,6)} seconds with duration {np.round(ns_gap_dur,6)} seconds")
end_locs[long_duration_indexes[loc]] = end_locs[long_duration_indexes[loc+1]]
long_duration_indexes = np.delete(long_duration_indexes, short_non_silence_gap_locs + 1)
if args.show_silence:
if len(long_duration_indexes)==0:
if args.verbose: print("No periods of silence found")
else:
if args.verbose: print("Periods of silence shown below")
fmt_str = "%-12s %-12s %-12s"
print(fmt_str % ("start","end","duration"))
for idx in long_duration_indexes:
start = start_locs[idx]
end = end_locs[idx]
duration = end - start
print(fmt_str % (np.round(start*Ts,6),np.round(end*Ts,6),np.round(duration*Ts,6)))
if args.verbose: print("")
return start_locs[long_duration_indexes], end_locs[long_duration_indexes]
def trim_data(start_locs,end_locs):
global data
if len(start_locs)==0: return
keep_at_start = int(silence_duration_samples / 2)
keep_at_end = int(silence_duration_samples - keep_at_start)
start_locs = start_locs + keep_at_start
end_locs = end_locs - keep_at_end
delete_locs = np.concatenate([np.arange(start_locs[idx],end_locs[idx]) for idx in range(len(start_locs))])
data = np.delete(data, delete_locs, axis=0)
def output_data(start_locs,end_locs):
global data
if args.verbose: print(f"Output File Duration = {np.round(data.shape[0]*Ts,6)}\n")
if args.time_it: print(f"Writing out data to {args.output}... ",end="",flush=True)
if using_scipy:
wavfile.write(args.output, sample_rate, data)
else:
packed_buf = data.astype(format_).tobytes()
with wave.open(args.output,"wb") as wavout:
wavout.setparams(params) # same params as input
wavout.writeframes(packed_buf)
start = time.time()
if not args.verbose and args.time_it: print("Detecting silence... ",end="",flush=True)
detect_silence_in_channels()
(start_locs,end_locs) = get_silence_locations()
end = time.time()
if not args.verbose and args.time_it: print(f"complete (took {np.round(end-start,6)} seconds)")
if args.detect_only:
if args.verbose: print("Not trimming, because 'detect only' flag was set")
else:
if args.time_it: print("Trimming data... ",end="",flush=True)
start = time.time()
trim_data(start_locs,end_locs)
end = time.time()
if args.time_it: print(f"complete (took {np.round(end-start,6)} seconds)")
start = time.time()
output_data(start_locs, end_locs)
end = time.time()
if args.time_it: print(f"complete (took {np.round(end-start,6)} seconds)")
If you want a script that assumes 16-bit PCM and without all the extra print statements and what not:
import numpy as np
from scipy.io import wavfile
# Params
(infile,outfile,threshold_db,silence_dur,non_silence_dur,mode) = ("test_stereo.wav","result.wav",-25,0.5,0.1,"all")
silence_threshold = np.round(10**(threshold_db/20.),6) * 32768 # Convert from dB to linear units and scale, assuming 16-bit PCM input
# Read data
Fs, data = wavfile.read(infile)
silence_duration_samples = silence_dur * Fs
if len(data.shape)==1: data = np.expand_dims(data,axis=1)
# Find silence
find_func = np.min if mode=="any" else np.max
combined_channel_silences = find_func(np.abs(data),axis=1) <= silence_threshold
combined_channel_silences = np.pad(combined_channel_silences, pad_width=1,mode='constant',constant_values=0)
# Get start and stop locations
starts = combined_channel_silences[1:] & ~combined_channel_silences[0:-1]
ends = ~combined_channel_silences[1:] & combined_channel_silences[0:-1]
start_locs = np.nonzero(starts)[0]
end_locs = np.nonzero(ends)[0]
durations = end_locs - start_locs
long_durations = (durations > silence_duration_samples)
long_duration_indexes = np.nonzero(long_durations)[0]
# Cut out short non-silence between silence
if len(long_duration_indexes) > 1:
non_silence_gaps = start_locs[long_duration_indexes[1:]] - end_locs[long_duration_indexes[:-1]]
short_non_silence_gap_locs = np.nonzero(non_silence_gaps <= (non_silence_dur * Fs))[0]
for loc in short_non_silence_gap_locs:
end_locs[long_duration_indexes[loc]] = end_locs[long_duration_indexes[loc+1]]
long_duration_indexes = np.delete(long_duration_indexes, short_non_silence_gap_locs + 1)
(start_locs,end_locs) = (start_locs[long_duration_indexes], end_locs[long_duration_indexes])
# Trim data
if len(long_duration_indexes) > 1:
if len(start_locs) > 0:
keep_at_start = int(silence_duration_samples / 2)
keep_at_end = int(silence_duration_samples - keep_at_start)
start_locs = start_locs + keep_at_start
end_locs = end_locs - keep_at_end
delete_locs = np.concatenate([np.arange(start_locs[idx],end_locs[idx]) for idx in range(len(start_locs))])
data = np.delete(data, delete_locs, axis=0)
# Output data
wavfile.write(outfile, Fs, data)

AttributeError: 'NoneType' object has no attribute 'get_width'

This is simple script on Ascii art generator from image , I get this error :
I run it in cmd line , and I am using windows 7 operating system
Traceback (most recent call last):
File "C:\Python33\mbwiga.py", line 251, in <module>
converter.convertImage(sys.argv[-1])
File "C:\Python33\mbwiga.py", line 228, in convertImage
self.getBlobs()
File "C:\Python33\mbwiga.py", line 190, in getBlobs
width, height = self.cat.get_width(), self.cat.get_height()
AttributeError: 'NoneType' object has no attribute 'get_width'
what am I messing here..?? can some one help..?
Here is full source code some one asked :
import sys
import pygame
NAME = sys.argv[0]
VERSION = "0.1.0" # The current version number.
HELP = """ {0} : An ASCII art generator. Version {1}
Usage:
{0} [-b BLOB_SIZE] [-p FONT_WIDTH:HEIGHT] [-c] image_filename
Commands:
-b | --blob Change the blob size used for grouping pixels. This is the width of the blob; the height is calculated by multiplying the blob size by the aspect ratio.
-p | --pixel-aspect Change the font character aspect ratio. By default this is 11:5, which seems to look nice. Change it based on the size of your font. Argument is specified in the format "WIDTH:HEIGHT". The colon is important.
-c | --colour Use colour codes in the output. {0} uses VT100 codes by default, limiting it to 8 colours, but this might be changed later.
-h | --help Shows this help.""""
.format(NAME, VERSION)
NO_IMAGE = \
""" Usage: %s [-b BLOB_SIZE] [-p FONT_WIDTH:HEIGHT] image_filename """ % (NAME)
import math
CAN_HAS_PYGAME = False
try:
import pygame
except ImportError:
sys.stderr.write("Can't use Pygame's image handling! Unable to proceed, sorry D:\n")
exit(-1)
VT100_COLOURS = {"000": "[0;30;40m",
"001": "[0;30;41m",
"010": "[0;30;42m",
"011": "[0;30;43m",
"100": "[0;30;44m",
"101": "[0;30;45m",
"110": "[0;30;46m",
"111": "[0;30;47m",
"blank": "[0m"}
VT100_COLOURS_I = {"000": "[0;40;30m",
"001": "[0;40;31m",
"010": "[0;40;32m",
"011": "[0;40;33m",
"100": "[0;40;34m",
"101": "[0;40;35m",
"110": "[0;40;36m",
"111": "[0;40;37m",
"blank": "[0m"}
# Convenient debug function.
DO_DEBUG = True
def debug(*args):
if not DO_DEBUG: return # Abort early, (but not often).
strrep = ""
for ii in args:
strrep += str(ii)
sys.stderr.write(strrep + "\n") # Write it to stderr. Niiicce.
# System init.
def init():
""" Start the necessary subsystems. """
pygame.init() # This is the only one at the moment...
# Get a section of the surface.
def getSubsurface(surf, x, y, w, h):
try:
return surf.subsurface(pygame.Rect(x, y, w, h))
except ValueError as er:
return getSubsurface(surf, x, y, w - 2, h - 2)
# The main class.
class AAGen:
""" A class to turn pictures into ASCII "art". """
def __init__(self):
""" Set things up for a default conversion. """
# Various blob settings.
self.aspectRatio = 11.0 / 5.0 # The default on my terminal.
self.blobW = 12 # The width. Also, the baseline for aspect ratio.
self.blobH = self.aspectRatio * self.blobW # The height.
self.blobList = []
self.cat = None # The currently open file.
self.chars = """##%H(ks+i,. """ # The characters to use.
self.colour = False # Do we use colour?
def processArgs(self):
""" Process the command line arguments, and remove any pertinent ones. """
cc = 0
for ii in sys.argv[1:]:
cc += 1
if ii == "-b" or ii == "--blob":
self.setBlob(int(sys.argv[cc + 1]))
elif ii == "-p" or ii == "--pixel-aspect":
jj = sys.argv[cc + 1]
self.setAspect(float(jj.split(":")[1]) / float(jj.split(":")[0]))
elif ii == "-c" or ii == "--colour":
self.colour = True
elif ii == "-h" or ii == "--help":
print(HELP)
exit(0)
if len(sys.argv) == 1:
print(NO_IMAGE)
exit(0)
def setBlob(self, blobW):
""" Set the blob size. """
self.blobW = blobW
self.blobH = int(math.ceil(self.aspectRatio * self.blobW))
def setAspect(self, aspect):
""" Set the aspect ratio. Also adjust the blob height. """
self.aspectRatio = aspect
self.blobH = int(math.ceil(self.blobW * self.aspectRatio))
def loadImg(self, fname):
""" Loads an image into the store. """
try:
tmpSurf = pygame.image.load(fname)
except:
print("Either this is an unsupported format, or we had problems loading the file.")
return None
self.cat = tmpSurf.convert(32)
if self.cat == None:
sys.stderr.write("Problem loading the image %s. Can't convert it!\n"
% fname)
return None
def makeBlob(self, section):
""" Blob a section into a single ASCII character."""
pxArr = pygame.surfarray.pixels3d(section)
colour = [0, 0, 0]
size = 0 # The number of pixels.
# Get the density/colours.
for i in pxArr:
for j in i:
size += 1
# Add to the colour.
colour[0] += j[0]
colour[1] += j[1]
colour[2] += j[2]
# Get just the greyscale.
grey = apply(lambda x, y, z: (x + y + z) / 3 / size,
colour)
if self.colour:
# Get the 3 bit colour.
threshold = 128
nearest = ""
nearest += "1" if (colour[0] / size > threshold) else "0"
nearest += "1" if (colour[1] / size > threshold) else "0"
nearest += "1" if (colour[2] / size > threshold) else "0"
return VT100_COLOURS[nearest], grey
return grey
# We just use a nasty mean function to find the average value.
# total = 0
# for pix in pxArr.flat:
# total += pix # flat is the array as a single-dimension one.
# return total / pxArr.size # This is a bad way to do it, it loses huge amounts of precision with large blob size. However, with ASCII art...
def getBlobs(self):
""" Get a list of blob locations. """
self.blobList = [] # Null it out.
width, height = self.cat.get_width(), self.cat.get_height()
# If the image is the wrong size for blobs, add extra space.
if height % self.blobH != 0 or width % self.blobW != 0:
oldimg = self.cat
newW = width - (width % self.blobW) + self.blobW
newH = height - (height % self.blobH) + self.blobH
self.cat = pygame.Surface((newW, newH))
self.cat.fill((255, 255, 255))
self.cat.blit(oldimg, pygame.Rect(0, 0, newW, newH))
# Loop over subsections.
for row in range(0, height, int(self.blobH)):
rowItem = []
for column in range(0, width, self.blobW):
# Construct a Rect to use.
src = pygame.Rect(column, row, self.blobW, self.blobH)
# Now, append the reference.
rowItem.append(self.cat.subsurface(src))
self.blobList.append(rowItem)
return self.blobList
def getCharacter(self, value, colour = False):
""" Get the correct character for a pixel value. """
col = value[0] if colour else ""
value = value[1] if colour else value
if not 0 <= value <= 256:
sys.stderr.write("Incorrect pixel data provided! (given %d)\n"
% value)
return "E"
char = self.chars[int(math.ceil(value / len(self.chars))) % len(self.chars)]
return char + col
def convertImage(self, fname):
""" Convert an image, and print it. """
self.loadImg(fname)
self.getBlobs()
pval = "" # The output value.
# Loop and add characters.
for ii in converter.blobList:
for jj in ii:
ch = self.makeBlob(jj)
pval += self.getCharacter(ch, self.colour) # Get the character.
# Reset the colour at the end of the line.
if self.colour: pval += VT100_COLOURS["blank"]
pval += "\n" # Split it up by line.
pval = pval[:-1] # Cut out the final newline.
print(pval) # Print it.
# Main program execution.
if __name__ == "__main__":
init()
converter = AAGen()
converter.processArgs()
converter.convertImage(sys.argv[-1])
sys.exit(1)
The problem is hidden somewhere in the loadImg. The error says that self.cat is None. The self.cat could get the None when initialised at the line 97, or it was assigned the result of tmpSurf.convert(32) and the result of that call is None. In the first case, you should observe the message Either this is an unsupported format..., in the later case you should see the message Problem loading the image... as you are testing self.cat against None:
def loadImg(self, fname):
""" Loads an image into the store. """
try:
tmpSurf = pygame.image.load(fname)
except:
print("Either this is an unsupported format, or we had problems loading the file.")
return None
self.cat = tmpSurf.convert(32)
if self.cat == None:
sys.stderr.write("Problem loading the image %s. Can't convert it!\n"
% fname)
return None
By the way, return None is exactly the same as return without argument. Also, the last return None can be completely removed because any function implicitly returns None when the end of the body is reached.
For testing to None, the is operator is recommended -- i.e. if self.cat is None:.
Update based on the comment from May 31.
If you want to make a step further, you should really learn Python a bit. Have a look at the end of the original script (indentation fixed):
# Main program execution.
if __name__ == "__main__":
init() # pygame is initialized here
converter = AAGen() # you need the converter object
converter.processArgs() # the command-line arguments are
# converted to the object attributes
converter.convertImage(sys.argv[-1]) # here the conversion happens
sys.exit(1) # this is unneccessary for the conversion
If the original script is saved in the mbwiga.py, then you can or call it as a script, or you can use it as a module. In the later case, the body below the if __name__ == "__main__": is not executed, and you have to do it in the caller script on your own. Say you have test.py that tries to do that. Say it is located at the same directory. It must import the mbwiga. Then the mbwiga. becomes the prefix of the functionality from inside the module. Your code may look like this:
import mbwiga
mbwiga.init() # pygame is initialized here
converter = mbwiga.AAGen() # you need the converter object
# Now the converter is your own object name. It does not take the mbwiga. prefix.
# The original converter.processArgs() took the argumens from the command-line
# when mbwiga.py was called as a script. If you want to use some of the arguments
# you can set the converter object's attributes the way that is shown
# in the .processArgs() method definition. Or you can call it the same way to
# extract the information from the command line passed when you called the test.py
#
converter.processArgs()
# Now the conversion
converter.convertImage('myImageFilename.xxx') # here the conversion happens

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