Questions tagged [python-bytearray]
38 questions
13
votes
1 answer
How to decode base64 String directly to binary audio format
Audio file is sent to us via API which is Base64 encoded PCM format. I need to convert it to PCM and then WAV for processing.
I was able to decode -> save to pcm -> read from pcm -> save as wav using the following code.
decoded_data =…
ddd
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11
votes
1 answer
Does slicing a bytes object create a whole new copy of data in Python?
Say I have very large bytes object (after loading binary file) and I want to read parts by parts and advance the starting position until it meets the end. I use slicing to accomplish this. I'm worried that python will create completely new copy each…
Tekz
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9
votes
3 answers
Is it possible to effectively initialize bytearray with non-zero value?
I need to have huge boolean array. All values should be initialized as "True":
arr = [True] * (10 ** 9)
But created as above it takes too much memory. So I decided to use bytearray for that:
arr = bytearray(10 ** 9) # initialized with zeroes
Is…
Mikhail M.
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7
votes
1 answer
How to implement readinto() method
I would like to implement a class which inherits from RawIOBase. I'm struggling to implement the readinto method. Basically, I don't know how to alter the content of the bytearray object passed as a parameter.
I've tried following (naive)…
Luke
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5
votes
1 answer
Python 3.73 inserting into bytearray = "object cannot be re-sized"
I'm working with a bytearray from file data. I'm opening it as 'r+b', so can change as binary.
In the Python 3.7 docs, it explains that a RegEx's finditer() can use m.start() and m.end() to identify the start and end of a match.
In the question…
rdtsc
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5
votes
1 answer
Append string to bytearray
I have a byte array, arr and a hexadecimal number a:
arr = bytearray()
a = 'FE'
How can I append this number to bytearray to have the same value, FE? I tried with print(int(a, 16)), but it seems to be a bad idea (it prints 254 instead of FE).
yak
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3
votes
2 answers
TypeError: 'bytearray' object cannot be interpreted as an integer
I want to send audio data over HTTP, but I don't understand why I'm getting this exception:
Exception happened during processing of request from ('127.0.0.1', 59976)
Traceback (most recent call last):
File "/usr/lib/python3.6/socketserver.py",…
valioiv
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2
votes
2 answers
Numpy array: get the raw bytes without copying
I am trying to concatenate the bytes of multiple Numpy arrays into a single bytearray to send it in an HTTP post request.
The most efficient way of doing this, that I can think of, is to create a sufficiently large bytearray object and then write…
Bashir Abdelwahed
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2
votes
2 answers
Python string contains byte array
I've experimented with the Python module named array a bit. It has got a way to encode arrays to strings.
>>>from array import…
Uncle Dino
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1
vote
1 answer
Compare every 3rd value inside a python dictionary and slice them
I have the following python dictionary with bytearray as values
test_bytearray_dict=
{'test_array0': bytearray(b'0000000000000000'),
'test_array1': bytearray(b'0000000001000000'),
'test_array2': bytearray(b'0000000002000000'),
'test_array3': …
learn_to_code
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1
vote
0 answers
Python decode bytearray
I need send some data over serialport, but I have problem with bytearray
I wrote simple script, like this:
msg = bytearray([255,1,134,0,0,0,0,121])
print(msg)
But output from this looks like this:
python3…
sosnus
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- 10
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1
vote
1 answer
python string decode displayed as byte array in list context
Why is this string printing as a byte array in the context of a list, printing as expected in a print statement, and the type is of string, not bytearray?
stringList = []
# Comparing a string, and a string decoded from a byte array
theString =…
Joe
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1
vote
1 answer
How to store PagingState in Cassandra Python driver?
I'm implementing a REST API which behind the scenes queries Cassandra (via Python driver) and returns the result. Now the items to be queried will be huge so I want to have pagination capability.
The ResultSet returned by execute() method has a…
Sivaprasanna Sethuraman
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1
vote
1 answer
Behavior of byte arrays indexing in python 3
Run across this:
import sys; print('Python %s on %s' % (sys.version, sys.platform))
Python 3.7.6 (tags/v3.7.6:43364a7ae0, Dec 19 2019, 00:42:30) [MSC v.1916 64 bit (AMD64)] on win32
b'\n' == b'\n'
True # well obviously
b'\n'[-1] == b'\n'
False #…
Mr_and_Mrs_D
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1
vote
1 answer
Faster bytearray list comprehension / conversion?
I have a bytearray of 2^18 (262144) bytes.
The goal is to convert it to a numpy array of complex values.
Packing within the bytearray is:
[0:1] Imaginary_0 16bit
[2:3] Real_0 16bit
[4:5] Imaginary_1 16bit
[6:7] Real_1 16bit
........
[262140:262141]…
Borisw37
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