This document provides an overview of audio compression technologies. It discusses what audio is, why compression is needed, and the main types of audio compression: lossy and lossless. It describes some standard codecs for each type including MP3, AAC, FLAC. It explains the MPEG audio encoding and decoding process, and notes that AAC is the successor to MP3. In summary, the document covers audio fundamentals and provides details on common audio compression standards and techniques.
Audio Compression Techniques
a type of lossy or lossless compression in which the amount of data in a recorded waveform is reduced to differing extents for transmission respectively with or without some loss of quality, used in CD and MP3 encoding, Internet radio.
Dynamic range compression, also called audio level compression, in which the dynamic range, the difference between loud and quiet, of an audio waveform is reduced
Linear Predictive Coding (LPC) is one of the most powerful speech analysis techniques, and one of the most useful methods for encoding good quality speech at a low bit rate. It provides extremely accurate estimates of speech parameters, and is relatively efficient for computation.
Audio Compression Techniques
a type of lossy or lossless compression in which the amount of data in a recorded waveform is reduced to differing extents for transmission respectively with or without some loss of quality, used in CD and MP3 encoding, Internet radio.
Dynamic range compression, also called audio level compression, in which the dynamic range, the difference between loud and quiet, of an audio waveform is reduced
Linear Predictive Coding (LPC) is one of the most powerful speech analysis techniques, and one of the most useful methods for encoding good quality speech at a low bit rate. It provides extremely accurate estimates of speech parameters, and is relatively efficient for computation.
What is Video Compression?, Introduction of Video Compression. Motivation, Working Methodology of Video Compression., Example, Applications, Needs of Video Compression, Advantages & Disadvantages
What is Video Compression?, Introduction of Video Compression. Motivation, Working Methodology of Video Compression., Example, Applications, Needs of Video Compression, Advantages & Disadvantages
Audio is an electrical or other representation of sound.
An audio file format is a file format for storing digital audio data on a computer system.
It can be a raw bitstream, but it is usually a container format or an audio data format with a defined storage layer.
Codec stands for enCOder/DECoder or COmpressor/DECompressor. It is a software or hardware that compresses and decompresses audio and video data streams.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
2. Introduction
What Is Audio?
Why Compression is needed?
Audio Compression.
Types Of Audio Compression.
Standard codecs for audio compression.
Categories of Audio Files
MPEG Audio Encoding Steps
MPEG Audio decoding
Successor of MP3
3. High quality audio coding based on perceptual models has
found its way to widespread application in broadcasting and
Internet audio (e.g. mp3).
Algorithms defined by the MPEG group (MPEG-1 Audio, e.g.
MPEG Layer-3 (mp3), MPEG-2 Advanced Audio Coding,
MPEG-4 Audio including its different functionalities) still
define the state of the art.
4. Audio is an electrical or other
representation of sound.
An audio file format is a file
format for storing digital audio
data on a computer system.
5. • Compression is the reduction in size of data in order to
save space or transmission time.
• Compression can be used to:
Reduce File Size
Save disk space
Reduce transmission time
• Compression is performed by a program that uses an
algorithm to determine how to compress or decompress
data.
6. • Audio compression is a form of data compression designed
to reduce the size of audio files.
• There is a conditions on this definition :
the audio file must still be playable after
compression, without decompressing it to original size
when you want to play it (for example with WinRAR).
If the file is compressed 'too much' there will be loss
of quality.
The compression is done with a thing called a codec.
This is an aggregation of the words: compressor and
decompressor.
This codec is a special algorithm to reduce the size.
7.
8. There are mainly two types of audio compression show
below:
1)Lossy Compression(MP3)
2)Lossless Compression(Winzip)
9. • A compression technique that does not decompress data
back to 100% of the original.
• Lossy methods provide high degrees of compression
and result in smaller compressed files, but there is a
certain amount of visual loss when restored.
• Example:MP3
10. • A compression technique that decompresses
data back to its original form without any loss.
• The decompressed file and the original are
identical. For example, the ZIP archiving
technology (WinZip...) is the most widely used
lossless method.
11. • Lossless audio files typically require more storage
space than Lossy encoded ones.
• However this type of format is often favored by users
wanting to backup original audio CDs.
• A perfect copy can be restored in the event of loss or
damage to the CD. FLAC, Apple Lossless (ALAC) and
WMA Lossless are examples of lossless compression
formats.
12. For lossy compression:
• Nero AAC Codec (Nero “advanced audio coding”
codec): It was developed and distributed by Nero AG.
• FAAC(Freeware Advanced Audio Coder):is an audio
compression computer program that creates AAC sound
files from other formats , it is the recommended format
for the company's iPod music player.
13. For lossless compression
• LPAC (Lossless predictive audio compression):is an
improved lossless audio compression algorithm developed
by Tilman Liebchen, Marcus Purat and Peter Noll.
• ALAC (Apple Lossless Audio Codec):is an audio coding
format, and its reference audio codec implementation,
developed by Apple.
• FLAC(Free Lossless Audio Codec): can typically reduce
the original size of audio file to 50–60%, and decompressed
it to an identical copy of the original audio data, developed
by Josh Coalson.
• WMA Lossless (Windows Media Audio Lossless):
developed by Microsoft
14. Moving Picture Experts Group
Aim to create standards relating to synchronized
audio and video compression
MPEG-1
MPEG-2
15. Quite good
high bit-rate is
available
Digital audio tap
Complex
Digital Audio
Broadcasting
most complex
audio transmission
over ISDN lines
16. There are 3 categories in which certain Audio files
belong to:-
1) Uncompressed:
Ex) .Wav
2) Lossless:
Ex) .WMA
3) Lossy:
Ex) .Mp3
17.
18.
19.
20.
21.
22.
23.
24. ◦ Hearing threshold level – a function of frequency
◦ Any frequency components below the threshold will
not be perceived by human ear
25. A frequency component can be partly or fully masked by
another component that is close to it in frequency
A lower tone can effectively mask higher tone
This shifts the hearing threshold
26. ◦ A quieter sound can be masked by a louder
sound if they are temporally close Sounds that
occur both (shortly) before and after volume
increase can be masked
27.
28. Power-law: larger values have less accuracy
quantization: uniform or non-uniform quantization.
coding: quantized spectral components are transmitted
either directly, or as entropy coded words (Huffman
coding)
For better data compression, variable- length Huffman
codes are used to encode the quantized samples.
Resultant bitstream is now reduced, because of coarser
quantisation, but can be further reduced by the use of
Huffman coding.
29. formats encoded quantized samples into an
encoded bit stream – final form in which the
compressed signal is transmitted.
Header (First 4 bytes of a frame)
◦ Contains: Frame Sync, MPEG Layer, Sampling Frequency,
Number of Channels, CRC, etc.
◦ Variable bit rate mp3’s switch bitrate between frames
30. Decoder side relatively easier. The gain, scale
factor, quantization steps recovered and used for
reconstruct the filter bank responses
Filter bank responses are combined to reconstruct
the decoded audio signal
31. Advanced Audio Coding (AAC) – now part of MPEG-
4 Audio
Inclusion of 48 full-bandwidth audio channels
Default audio format for iPhone, iPad, Nintendo,
PlayStation, Nokia, Android, BlackBerry
Introduced 1997 as MPEG-2 Part 7
In 1999 – updated and included in MPEG-4
standard for lossy digital audio compression. Designed
to be the successor of the MP3 format, AAC generally
achieves better sound quality than MP3 at similar bit
rates.
32. Opus is a lossy audio coding format developed by the
Internet Engineering Task Force (IETF) that is
particularly suitable for interactive real-time
applications over the Internet.
Opus incorporates technology from two other audio
coding formats: the speech-oriented SILK and the low
latency CELT.
33. The MDCT was proposed by Princen, Johnson, and
Bradley[1] in 1987, following earlier (1986) work by
Princen and Bradley[2] to develop the MDCT’s
underlying principle of time-domain aliasing
cancellation (TDAC), described below.
In MP3, the MDCT is not applied to the audio signal
directly, but rather to the output of a 32-band polyphase
quadrature filter (PQF) bank. The output of this MDCT
is post processed by an alias reduction formula to
reduce the typical aliasing of the PQF filter bank.
34. Such a combination of a filter bank with an MDCT is
called a hybrid filter bank or a sub band MDCT. AAC,
on the other hand, normally uses a pure MDCT; only
the (rarely used) MPEG-4 AAC-SSR variant (by Sony)
uses a four band PQF bank followed by an MDCT.
Similar to MP3, ATRAC uses stacked quadrature
mirror filters (QMF) followed by an MDCT.
35. ISO/IEC
• MPEG-1 Layer III (MP3)
• MPEG-1 Layer II
• MPEG-1 Layer I
• AAC
• MPEG-4 ALS
• MPEG-4 SLS
• MPEG-D USAC