# What does downsample mean in Matlab?

## What does downsample mean in Matlab?

y = downsample( x , n ) decreases the sample rate of x by keeping the first sample and then every n th sample after the first. If x is a matrix, the function treats each column as a separate sequence. y = downsample( x , n , phase ) specifies the number of samples by which to offset the downsampled sequence.

### How do you downsample a signal?

Downsampling by an integer factor. Rate reduction by an integer factor M can be explained as a two-step process, with an equivalent implementation that is more efficient: Reduce high-frequency signal components with a digital lowpass filter. Decimate the filtered signal by M; that is, keep only every Mth sample.

#### What does it mean to downsample data?

Downsampling is the process of reducing the sampling rate of a signal. Downsample reduces the sampling rate of the input AOs by an integer factor by picking up one out of N samples. Note that no anti-aliasing filter is applied to the original data.

**What is meant by downsampling?**

(1) To make a digital audio signal smaller by lowering its sampling rate or sample size (bits per sample). Downsampling is done to decrease the bit rate when transmitting over a limited bandwidth or to convert to a more limited audio format.

**Why do we need downsampling?**

Downsampling (i.e., taking a random sample without replacement) from the negative cases reduces the dataset to a more manageable size.

## How do you downsample data?

Downsampling. The idea of downsampling is remove samples from the signal, whilst maintaining its length with respect to time. For example, a time signal of 10 seconds length, with a sample rate of 1024Hz or samples per second will have 10 x 1024 or 10240 samples.

### Why is downsampling needed?

Downsampling enables you to create even smaller models since the machine learning algorithm doesn’t require as many training data points. For embedded AI, memory usage is vital; creating a smaller but still highly accurate model allows you to save space for other application code and processes on the device.

#### When should you downsample data?

Downsampling is also helpful for model reusability between devices whose sensors record at different sampling rates. For example, I could record audio samples on my mobile phone at 16kHz and train a model using that data, but deploy to an embedded device like the Micro:bit with a microphone frequency of 11kHz.

**How is downsampling done?**

**Why is Downsampling needed?**