Understanding Audio Quality: Bit Rate, Sample Rate

Audio Quality is the accuracy and enjoyability of the audio which the user can listen from an electronic device. Audio quality depends upon the bit rate, sample rate, file format and encoded method. It also depends on the ability of the encoder to get the important bits right.

Bit Rate refers to the audio quality of the stream. It is measured in Kilobitspersec(kbps or k).  Bit rate is no of bits (data) encoded per second or the no. of bits transmitted or received per second. Higher the bit rate with more sampling rate, requires high bandwidth and produces good audio quality. Low bit rates refer to smaller file size and less bandwidth with a drop in audio quality. For good quality music usually 64-128kbps(96kbps+ recommended) bit rate is preferred.

Sample Rate is the number of samples per unit time. A sample is a measurement of signal amplitude and it contains the information of the amplitude value of the signal waveform over a period of time. The sample rate is also called as sample frequency, higher the sample frequency obtains a signal which is similar to original analog signal for good audio quality. The file size depends upon the sample frequency. The bit depth refers to no. of bits in each sample, determines the maximum signal to noise ratio. The bit depth may be 16-bit, 24-bit, 32-bit, for audio  CD 16-bit is preferred. The sample rate is measured in hertz(Hz). According to Nyquist Sampling theorem the sampling frequency to produce the exact original waveform should be double the original frequency of the signal. The human hearing bandwidth is 20Hz-20kHz, the audio sampled can be at the rate above 40kHz.(Usually 44.1KHz is preferred).

Bandwidth is the speed that you can send data or receive the data.It depends upon the bit rate at which the data is send or received.For more bit rate the bandwidth consumed is more for which the cost to  broadcaster will increase. As the bit rate increases the amount of data streamed per second increases at a good sampling rate  to produce the replica of analog signal with more bit depth(16 for audio) thus increasing the bandwidth and file size to produce the best audio quality. Some of the bit rate and sample rate preferred are given below: For MP3format the Mp3 streaming bit rates and sample rate for stereo may range from 96-320 kbps/44.1-48KHz, the preferred bit rates are 128Kbps/44.1KHz, 96Kbps/44.1KHz. The audio quality depends on the encoded format, it is difficult to determine which encoded format at chosen bit rate sounds good. For example the bit rate at 128kbps Mp3 format sounds the same quality as AAC format at 96kbps/44.1KHz(apple lossy compressed format for itunes).

Bit Rate calculation(Uncompressed Format) bit rate=bitspersample(16-bit or 24-bit)*samplespersec(44.1KHz-48KHz)*no.of channels. Example 16-bit 48Khz strereo contains bitrate of 1.5Mb/sec. File size calculation For Uncompressed Format file size=((bitspersample(16-bit or 24-bit)*samplespersec(44.1KHz-48KHz)*no.of channels*duration(no.of sec the music played))/8. Example 16-bit 44.1Khz stereo for 60 min the file size is 630MB. For Compressed Format File size=((bit rate in kbps)*(length of the audio in sec))/8 Example 16 bit 44.1Khz stereo for 60min at 128Kbps the file size is 10.8MB For live streaming the bandwidth required can be calculated using the formula: bandwidth=listeners*bit rate*length(audio length per day)*no. of days. The bandwidth required for  bit rate of 128Kbps is 57.6MB/hr. Table Representing the bandwidth for various Bitrates The length of the file is taken as  60min(180 sec)

 

Bit Rate Bit Size(bit) Channel Sample Rate File Size(Uncompressed) BandWidth Consumed No. of hrs for 1GB Audio
24kbps 16 Stereo 44.1KHz 630MB 10.8MB/hr 92
56kbps 16 Stereo 44.1KHz 630MB 25.2MB/hr 39
56kbps 24 Stereo 44.1KHz 948MB 25.2MB/hr 39
96kbps 16 Stereo 44.1KHz 630MB 43.2MB/hr 23
128kbps 24 Stereo 44.1KHz 948MB 57.6MB/hr 17
128kbps 16 Stereo 44.1KHz 691MB 57.6MB/hr 17
128kbps 16 Mono 48KHz 342MB 57.6MB/hr 17
128kbps 16 Stereo 22KHz 316MB 57.6MB/hr 17
196kbps 16 Stereo 44.1KHz 630MB 88.2MB/hr 11
196kbps 16 Mono 44.1KHz 342MB 88.2MB/hr 11

To Know more about our Django CRM(Customer Relationship Management) Open Source Package. Check code

Posted On 23 January 2011 By MicroPyramid


Need any Help in your Project?Let's Talk

Latest Comments
Unit testing with selenium-python

Unit testing with selenium-python. Unit test case example to test the front-end

Continue Reading...
Tips to choose the best custom software development company

Choosing the best company for your software development needs is the most important step. This blog explains you tips to outsource custom software development services.

Continue Reading...
WSGI explanation with simple APP

The main goal of WSGI is to facilitate easy interconnection of servers and web frameworks/applications. WSGI defines a standerd API for web servers(uWSGI, Twisted, Gunicorn) …

Continue Reading...
Understanding self and __init__ method in python Class.

Understand self and __init__ method in python Class?
Before understanding the "self" and "__init__" methods in python class, it's very helpful if we have the idea …

Continue Reading...
List of python class special methods or magic methods

python class special methods or magic methods. magic methods allow us to override or add the default functionality of python objects. One of the biggest …

Continue Reading...
Building and Parsing XML Document using Python

Creating XML document with required elements, Then Parsing it using Python to generate a serialized form of its contents.

Continue Reading...
Working with python collections Counter

Python collections - Counter is to count the frequency of character, OrderedDict is to track the order of the contents in which they are added …

Continue Reading...
Python to Debian package: Simple, Easy and Fast

Packaging python script to debian follows strict instructions, using the following instructions, most of the steps can be skipped hence making it easy and fast.
If …

Continue Reading...
Sending SMS, MMS using Twilio.

A simple Tutorial on sending SMS and MMS in python using Twilio. In this tutorial you will learn how to send SMS, MMS and checking …

Continue Reading...
Customize and Embed Vimeo Videos using Python Requests.

Using python requests and vimeo endpoints it becomes very easy and simple to upload our videos and customize them.

Vimeo Access token:
1. Create an …

Continue Reading...
Getting Started with the IPython Notebook

IPython is a set of tools developed to make it easier for the programmers to work with Python and data. IPython provides extensions to the …

Continue Reading...
Python Arrow To Show Human Friendly Time

Arrow is a python library and command-line tool to genrerate, manipulate dates, times, timestamps.
use of arrow:
With the use of arrow, we can also create, manipulate, …

Continue Reading...
Working with python collections part 1

Python Collections - named tuple is to access by the names specified and deque is to append and pop the elements from both sides of …

Continue Reading...
Building Documentation with readthedocs

In this blog, I'm going to explain you how to write the Sphinx docs using reStructuredText to host in the Read the Docs.

Installing Sphinx

Continue Reading...
Create excel file, Insert image, Draw Bar Graphs in excel files in python using xlsxwriter

Xlsxwriter is a python module through which we can write data to Excel 2007+ XLSX file format. In this blog post we learn to write …

Continue Reading...
Integrate Twitter Social API into Django App

Integrating Twitter sign in (OAuth) in Django App, which includes
1. Capturing username via Twitter Login
2. Updating authenticated user current status on twitter(tweets).

Continue Reading...
How to implement Case Insensitive CSV DictReader in python

In general use cases we upload the CSV files to the system to store huge amount of data by uploading single file. For example in …

Continue Reading...
Python using yield and generators.

Generators are memory efficient. They allow us to code with minimum intermediate arguments, less data structures. Generators are of two types, generator expressions and generator …

Continue Reading...
Introduction to Object Oriented Programming with Python 3

Introduction to Object Oriented Programming with Python

Continue Reading...
Python Coding Techniques and Programming Practices

Coding techniques and programming practices are one of the features of a professional programmer. While writing code to solve a problem programmer should make simple …

Continue Reading...
FABRIC – LEARNING PART 2

Using Fabric, we can develop interactive script for ec2 region, ec2 flavour amazon web services. For this, you need aws account, security group, key pair, …

Continue Reading...
Generating PDF Files in Python using xhtml2pdf

There are many ways for generating PDF in python. In this post I will be presenting PDF files generation with xhtml2pdf.

xhtml2pdf: xhtml2pdf is a …

Continue Reading...
Using Python xlwt generating CSV writer and Excel files

In most of the cases, you need to export the data from your database to different formats. In this post I will show you how …

Continue Reading...
How to access development server publicly using Localtunnel

We do need to expose our local server to hit call-back URLs while programming with other APIs. There is a tool called local tunnel from …

Continue Reading...
How to generate PDF Files from HTML In Python using PDFKIT

There are many approches for generating PDF in python. pdfkit is one of the better approache as, it renders HTML into PDF with various image …

Continue Reading...
Converting Audio and Video files using FFMPEG Tool

FFMPEG is a command-line tool that converts audio or video to required formats, which handle multimedia data. It can also capture and encode in real-time.

Continue Reading...
Python Web Scraping with Beautiful soup

Download all One Piece animation series episodes by scraping site using BeautifulSoup python library.

Continue Reading...
Publishing Python Modules with PIP via PyPi

We'll install so many packages in our day to day python development. Now in this blog post, we'll try to know how to create our …

Continue Reading...
Programming with python: Decorators

Python decorators supports aspect-oriented programming. It is used to add or modify code in functions or classes. Using decorators will provide security, tracing, looking ..etc …

Continue Reading...
Vim for Python Web Development

Having a good environment setup is important for effective, fast and easy coding. We have different IDE's like eclipse, pycharm, sublime etc.. which are powerful …

Continue Reading...
Understanding Python Properties

Python Properties is a class for managing class attributes in Python. Property( ) is a built-in function that creates and returns a property object

Syntax:
attribute_name …

Continue Reading...
QRCode generation in python

A Quick Response code(QRCode) is a two-dimensional pictographic code used for its fast readability and comparatively large storage capacity. The code consists of black modules …

Continue Reading...
Understanding Audio Quality: Bit Rate, Sample Rate

Audio Quality is the accuracy and enjoyability of the audio which the user can listen from an electronic device. Audio quality depends upon the bit …

Continue Reading...
Programming with python Descriptors (_get_, _set_, _delete_) - MicroPyramid

Python descriptors are object attributes that are only invoked for new style of classes. Python descriptors comes under the category of meta programming(code that manipulates …

Continue Reading...
Debugging in Python

When something goes wrong with your code instead of using standard debugging techniques such as print statements use debugging tools. I found two great tools …

Continue Reading...
Python development environment on windows

Python is an interpreted, object-oriented, high-level programming language with dynamic semantics. Python's simple, easy to learn syntax emphasizes readability and therefore reduces the cost of …

Continue Reading...

Subscribe To our news letter

Subscribe and Stay Updated about our Webinars, news and articles on Django, Python, Machine Learning, Amazon Web Services, DevOps, Salesforce, ReactJS, AngularJS, React Native.
* We don't provide your email contact details to any third parties