Questions tagged [downsampling]
231 questions
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Why Open3D's VoxelDownSample behaves differently for legacy and tensor point clouds?
I noticed that VoxelDownSample behaves differently for legacy and tensor point clouds.
For legacy point clouds, all points that fall into single voxel are averaged. Howewer, for tensor point cloud all points seem to be centered in their voxels. It…
jellyf859
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1 answer
Conditional downsampling over a data frame
I am working on a data frame that looks like this:
Id feat1 value
c1 c22 51
c2 c12 83
c3 d31 42
c4 a19 110
c5 d44 56
. . .
. . .
. . .
The value column has a range [40,240]. I want to…
Kathan Vyas
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1 answer
Downsampling time series data in pandas
I have timeseries data that looks like this:
datetime generation
2022-01-31 00:00 1234
2022-01-31 00:15 4930
2022-01-31 00:30 2092
2022-01-31 00:45 20302
2022-01-31 01:00 483
2022-01-31 01:15 4924
2022-01-31…
Pixel
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Python: Resizing array by removing nth element
I have some dynamically created arrays that have varying lengths and I would like to resize them to the same 5000 element length by popping every n element.
Here is what I got so far:
import numpy as np
random_array =…
Martin Pedersen
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3 answers
Audio files down-sample
I am facing a problem while working with audio files. I am implementing an algorithm that deals with audio files, and the algorithm requires the input to be a 5 KHz mono audio file.
Most of the audio files I have are PCM 44.1 KHz 16-bit stereo, so…
Samer Makary
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Crossfilter for downsampling data in dc.js plot
I'm trying to downsample an array that has ~10,000,000 points based on the current zoom state.
The downsampling mechanism is through downsample module, using LTTB function; below is a simple example of how it's done crossfilter
const ARRAY_LENGTH =…
joshp
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Is there a way to set up downsampling option when fetching an image with SDWebImage?
This is how I set images to UIImageView from a web url:
import UIKit
extension UIImageView {
private var storage: Storageable {
Assembler.shared.resolve(Storageable.self)!
}
private var imageDownloader: ImageDownloaderable {
…
Bartłomiej Semańczyk
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python - downsampling with resample (D) skips days that don't have 00:00:00 data
i need to downsample a dataframe from hourly to daily. This is quite straightforward using pandas but I'm facing a problem that I'm failing to resolve.
Data frame looks like this:
datetime
prod
2018-03-13 19:00:00
38.700000
2018-03-13…
joelmoliv
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Time Series Downsampling/Upsampling
I am trying to downsample and upsample time series data on MonetDB.
Time series database systems (TSDS) usually have an option to make the downsampling and upsampling with an operator like SAMPLE BY (1h).
My time series data looks like the…
AbdelKh
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1 answer
Downsampling data frome 25hz to 10hz
I have some time series data sampled at 25hz (25 samples per second)
time_in_secconds data_vals
199.655 0.549038
199.696 0.83472
199.736 0.478569
199.776 0.114157
199.817 0.217603
199.858 0.701952
199.898 0.23409
199.938 …
atomsmasher
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how to Upsample and Downsample ECG signals in python or MATLAB?
I have an ECG signal having 500 Hz frequency and a signal having 257 HZ frequency. To process both signals i want both signals having frequency 300 Hz. So how to downsmaple the first ECG signal to 300 Hz and upsample the 2nd ECG signal to 300 Hz in…
Wiqi Khan
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1 answer
Downsample from 1second to 1minute is creating new rows using resample pandas
I am new to python programming. I have a timeseries dateset in seconds which starts at 9.15am and ends at 3.30pm each day. I am trying to downsample it to 1 min timeframe.
Example of original data set:
Px_NIFTY 20140130…
abs
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1 answer
When decoding a jpeg how would I reverse chrominance downsampling in matlab?
Hi trying to make a simple jpeg compressor which also decompresses the image. I use the following code to downsample the chrominance of an image for the first step of jpeg compression.
resampler = vision.ChromaResampler;
[Cb, Cr] =…
user11234959
1
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1 answer
Filter table rows Matlab by matching non-identical numbers as close as possible
This may have a simpler solution than my current approach, so any recommendations welcome!
I have a MATLAB table (38327x17) of char/double variables imported from .csv with readtable(), double converted from char. The double variable in col 2 is…
Coco Newton
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0 answers
Downsample to equalize the counts for pairs of factor levels?
Suppose you have a factor variable whose level labels come in pairs
(such as 'a1' and 'a2', 'b1' and 'b2', etc.), and these pairs have unequal n-sizes.
x <- factor(c(rep("a1", 10), rep("a2", 15),rep("b1", 5), rep("b2", 30),rep("c1", 33), rep("c2",…
xilliam
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