Questions tagged [downsampling]
231 questions
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How to downsample a sequence x by an integer factor M with a single statement such as for loop or conditional statements
I have already learning to use downsample() function inside Matlab. However, I am wondering if it can be implemented using basic for loop or if statement. Can anyone help me?
P.S Below is the code I have worked out, I would like to know if there is…
WilliamW
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wave write function not working, what am I doing wrong?
I am trying to halve the existing sampling rate of a folder full of .wav files. This is the only way I have found to do it but it is not working. The read part works just fine up until f.close(), then the wave.write part causes the error.
import…
SHGrad
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Downsample the Time Series data of Accelerometer and Gyroscope
I have time series data for Physical Activities. The data was recorded at 50hz frequency. But now I want to down sample the data at 20hz because I want to train and predict model at 20hz.
Is there an efficient way in python to do that ? I've heard…
Arsalan Khan
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open3d voxel_size too small : down sampling not working for e57 binaries
I'm trying to downsample a point cloud. I have 2 data formats for different parts of my data.
The .bin files cause no problems, but when I'm trying to downsample the .e57 files I encounter a strange problem.
Here's what I do:
import numpy as…
Chris-Max-P
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How to repeat downSample in R?
I'm not sure what approach to take to this problem (I'm new to both R and statistical analysis). I have a highly imbalanced class in my data set:
PCL_Sum n
*
1 0 300
2 1 25
I realise that I could use…
Socsi2
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Picture size 0x0 is invalid: trying to downsample 4k raw video into 1080 using ffmpeg
ffmpeg -i CityAlley_3840x2160_50fps_8bit.yuv -vf scale=1920:1080 CityAlly.yuv
But I got the error:
ffmpeg version 4.2.4-1ubuntu0.1 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 9 (Ubuntu 9.3.0-10ubuntu2)
configuration:…
neetu sigger
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find overlap and downsample scatter plot
I have huge data that consist of points(x,y) and need to present in a scatter plot.
To find overlap and remove invisible differences between the same point, I wrote bellow code :
void DownSampler::makeDownSample(QVector keys,QVector…
SajadBlog
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How to "thin" a large CSV file to extract its salient features?
I need to downsample, or "thin", a large data set: 275 MB CSV file consisting of 10 Million data points. Each data point is a time,voltage pair formatted (for example) as follows:
3.387903904E-04,2.68E-02
or, 338.79 usec, 0.0268 volts
The data…
user5395338
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Need Help in resampling the dataset
I have a data set of dow_jones_index. I was asked to perform following activities:
downsample the data filtered in the above step day wise and perform
interpolation to forward fill the first two 'Nan' values.
return the first 10 samples of…
user12099710
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Resample audio in iOS
I have a wave file recorded in 48000 sample rate. I need to play the recorded audio file in BLE device configured with 44100 sample rate. When the BLE device is disconnected from iPhone, i need to resume the playback in iPhone speaker which is…
vinu
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Transforming a 3D numpy array to 2D and back
I am trying to use the imblearn random undersampler but I have the problem that my X_train is a 3D array and the undersampler needs a 2D array so I am getting the error:
Found array with dim 3. Estimator expected <= 2.
So I tried the solution…
Kirk1746
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What is the difference between bins when using groupby apply vs resample apply?
This is somewhat of a broad topic, but I will try to pare it to some specific questions.
I have noticed a difference between resample and groupby that I am curious to learn about. Here is some hourly time series data:
In[]:
import pandas as pd
dr…
Tom
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Bulk downsampling list of wave objects using seewave::resamp
I am trying to downsample a list of wave objects using seewave::resamp.
To get my list I have imported a .wav file and split it into 10 second clips following @Jota 's answer here
So to get my list of wave object I have done the following (this is…
TomCLewis
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Matrix assignement value error in opencv C++ with mat.at(i,j)
I am learning image processing with OpenCV in C++. To implement a basic down-sampling algorithm I need to work on the pixel level -to remove rows and columns. However, when I assign values with mat.at<>(i,j) other values are assign - things like…
joachim
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Downsample matrix from an image python
I need help to understand how to downsample a matrix from an image to a matrix of 10x10.
Libraries:
import sys
import cv2
import numpy
from PIL import Image
from numpy import array
I used PIL to get the image and used numpy to get the matrix array…
Khwaja Hussam Quasmi
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