This file includes image formate and video foramte with basic knowledge of codec.

1. •Image and Video
•formates
•Presented By:
• Prerak

2. •Video Basics

3. •Codec•
•
–A codec is an algorithm, which can be thought of
as a list of instructions that identifies the method
used to compress data into fewer bytes.
–By following these instructions, applications such
as encoders and players can reliably compress and
decompress data. In the case of digital media
content, codecs are used to decrease the content's
file size and bit rate (the amount of data per second
that is required to render audio and video content).
–With smaller file sizes and lower bit rates, digital
media content can be stored and streamed over a
network more quickly and easily.

4. •Introduction to Video,Persistence of Vision
The persistence of vision theory states that the
human eye holds a still image for a fraction of a
second, remaining on the retina long enough to blend
with the next image.
Film displays 24 still images each second (frames per
second or fps).

5. •How video compression works?
•Video compression works on square shaped group of
neighboring pixels called macroblocks.
•The group of pixels in different frames are compared
and only difference between them is sent so
redundancy is reduced and size is also reduced.
•So if there is much more motion in the movie then
compression doesn’t work efficiently and size is not
much reduced. Ex: Fire scenes, explosions
•So variable bitrate is increased to maintain the quality.

6. •MPEG
•What is MPEG?
•MPEG stands for the Motion Picture Experts
Group,which is part of the International Organization
for Standardization(ISO) and International
Electrotechnical Commission(IEC).
•However, MPEG is charged with creating and
• publishing standards for various technology.

7. •Video compression formates
•ISO/IEC:
•MPEG-1 MPEG-2 MPEG-4 ASP MPEG-4/AVC
•ITU-T:
•H.261 H.262 H.263 H.264
•Others:
•AVS Bink Dirac Indeo MJPEG RealVideo ·
Theora VC-1 VP6 VP7 WMV
•

8. •MPEG-1
•MPEG-1 video is used by the Video CD (VCD) format
and less commonly by the DVD-Video format.
•The quality at standard VCD resolution and bitrate is
near the quality and performance of a VHS tape.
•MPEG-1, Audio Layer 3 is the popular audio format
known as MP3.

9. •MPEG-2
•MPEG-2 is the core of most digital television and DVD
formats.
•It is widely used around the world to specify the
format of the digital television signals that are
broadcast by terrestrial (over-the-air), cable, and direct
broadcast satellite TV systems.
•It also specifies the format of movies and other
programs that are distributed on DVD and similar
disks.
•The standard allows text and other data, e.g., a
program guide for TV viewers

10. •MPEG-4
•MPEG-4 is the new worldwide standard for interactive
multimedia creation, delivery, and playback for the
Internet.
•What MPEG-1 and its delivery of full-motion , full-
screen
•video meant to the CD-ROM industry
•MPEG-2 meant to the development of DVD,
•MPEG-4 will mean to the Internet.

11. •MPEG-4•
•MPEG-4 AVC , H.264 :
• Apple QuickTime , IPOD , PSP
• MPEG-4 Part 2 , MPEG-4 ASP:
• DivX , Xvid

12. •WMV
•WMV is a generic name for the set of video codec
technologies developed by Microsoft. It is part of the
Microsoft Windows Media framework.

13. •Video File ( Container_format )
•MPEG-4 AVC ???
•H.264 ???
•DivX ????

14. •Different Container
•Standar
d owner
•Subtitles •Video formats supported •Audio formats supported
•3GP ,
3G2
•3GPP •3GPP Timed
Text
•MPEG-4, H.263 and
H.264/MPEG-4 AVC
•AMR-NB/WB, AMR-WB+ and
(HE)-AAC
•ASF •Microso
ft
•Yes •Almost anything through VFW
or DMO, H.264/AVC is
problematic
•Almost anything through ACM
or DMO, Vorbis is problematic
•AVI •Microso
ft
•Yes, via third
party
modifications
•Almost anything through
VFW, H.264/AVC is problematic
due to the limited b-frame
support[4]
•Almost anything through ACM,
Vorbis is problematic [5]
•DIVX •DivX •Yes •DivX video encoded to meet
DivX Profiles
•MP3, PCM, AC-3
•EVO •MPEG • ? •MPEG-2 Part 2, H.264/MPEG-
4 AVC, VC-1
•AC-3, E-AC-3, Dolby TrueHD,
Linear PCM, DTS, DTS-HD,
MPEG-2 Part 3

15. •Different Container
•Standard owner •Subtitles •Video formats
supported
•Audio formats
supported
•MKV , MKA •public domain •Yes, anything, including
embedded fonts
•Yes, anything •Yes, anything
•MCF •BSD-style license
for specs, GNU for
tools
•? •Anything •Anything
•MPEG •MPEG •Only in VOB files on
DVDs
•MPEG-1, MPEG-2 •MPEG-1 Layers I,
II, III (mp3), AC-3,
LPCM, DTS
•MPG •MPEG •possible via ETSI EN 300
743
•MPEG-1, MPEG-2,
MPEG-4 ASP,
H.264/MPEG-4 AVC
•MPEG-1 Layers I,
II, III (mp3), AC-3,
LPCM, DTS, AAC
•MOV •Apple •Yes •Anything through
QuickTime codec
manager
•Anything through
Sound Manager or
CoreAudio
•MP4 •MPEG •ttxt, VobSubs with privat
objectTypeIndication not
usable with the
sceneDescription (started
by Nero), BIFS
•MPEG-1, MPEG-2,
H.263, MPEG-4
ASP, H.264/MPEG-4
AVC
•MPEG-1 Layers I,
II, III (MP3),
MPEG-2/4 (HE)-
AAC, Vorbis (with
privat
objectTypeIndicatio
n), Apple Lossless

16. •Different Container
•Standard
owner
•Subtitles •Video formats supported •Audio formats
supported
•NUT •NUT
Project/GPL
•Yes •Virtually anything •Virtually anything
•OGG/OG
M
•Xiph.org •Ogg Writ, SRT and
MicroDVD with
OGMtools.
•Theora, almost anything
through VFW, H.264/AVC
doesn't work
•Vorbis, almost
anything through
ACM
•RMVB •RealNetworks •Yes •RealVideo 8, 9, 10 •(HE)-AAC, Cook
Codec, Vorbis,
RealAudio Lossless
•VOB •MPEG •VobSub •MPEG-2 Part 2 •AC-3, Linear PCM,
DTS, MPEG-2 Part
3, MPEG-1 Layer II

17. •Image Basics

18. •A digital image is a numeric representation of a two
dimensional image.
•Most software developers created a new custom file
format for each application they develop.
•Using Standardized file formats increases the ease with
which images can be exchanged and be readable by other
software .

19. •1-Tagged Image Format File (TIFF):•
•
–A TIFF file can contain a number of images with
different properties.
–
–A TIFF specification provide a range of different
compression methods;( LZW, ZIP, CCITT &
JPEG) and color spaces which make it easy to
store a number of variations of an image in different
sizes & representations together in a single TIFF
file.
–
–The flexibility of a TIFF has made it universal
exchange format used in archiving documents ,

20. •Merits of TIFF format:•
•
–The great advantage of saving files in the same
TIFF format is that no information is lost.
–
– Useful for transporting image files from one
application to another or from one computer to
another as they are designed to be independent of
any particular hardware or software.
–
– The strength of TIFF format lies in its
architecture , which enables new image types &
information blocks to be created by defining new
“tags” .

21. •Demerits of TIFF format:•
•
–TIFF files encounter errors when loading. In
flexibility also lies the weakness of this format
where proprietary tags are not always supported.
–
– The drawback of TIFF files is that the file size is
large. They take up a lot of space when stored and
take a long time to open in an application.
–
– Difficult to store. They are not useful as
embedded image files in a webpage as they take
much too long to download.

22. •2- Graphics Interchange Format (GIF) :•
•
–Widely popular format; due to its early support
for indexed color at multiple bit depths, LZW
compression, interlaced image loading.
–
– Designed for color & grayscale images with
maximum 8bit depth (i.e. doesn’t support true
color images). GIF files are designed to
efficiently encode flat images consisting of large
areas of the same color.
–
–Supports color palletes in the range of (2-256);
enabling pixels to be encoded using fewer bits.

23. •Merits of GIF format:•
•
•The limited color range has the advantage that GIF
files will be smaller in size.
•
• Easy to store and display: When saving an
image as GIF, you can specify how the image appears
as it is downloaded. Select “Interlaced” to display the
image gradually in increasing detail as it is
downloaded.
•
• GIF format has the ability to encode simple
animations by storing a number of images in a single
file for later sequential display. Also can be made into
a transparent image.

24. •Demerits of GIF format:•
• The limitation of an 8-bit palette, or 256 colors
makes the GIF format suitable for storing graphics with
relatively few colors such as simple diagrams,
shapes, logos & cartoon style images and ineffective
for detailed images or dithered images.
•
• Loss of color variation. GIF is not suitable
for subtle color variations retained in your image. Gif
formats are very useful for storing grey scale images
which are limited to 256 tones of grey, so that no
information is lost .

25. •3-Portable Network Graphics (PNG):•
•
•A universal image format designed especially for the
use of the internet. PNG format was designed to be an
alternative to the GIF format .
•
•PNG files support 3 types of images:
•1) true color (with up to 3*16 bits/pixel)
•2) grayscale (with up to 16bit/pixel)
•3) indexed (with up to 256 colors).
•
•PNG includes an alpha channel for transparency
with a maximum width of 16bit.

26. •Merits of PNG format:•
•
–Unlike GIF, the PNG format is able to retain full
16,000,000 colors. Still the format support one
image per file but it allows images of up to 2^30 *
2^30 pixels.
–
–The PNG format uses a lossless compression
method .
–
–

27. •Demerits of PNG format:
•
•
• Relative large file size ensures PNG format
may be less suitable for Web or other online service.

28. •4-Joint Photographic Experts Group (JPEG):
•
• It’s a standard defines a compression method
used to display continuous tone images (such as
photographs) with a goal of achieving an average data
reduction of 1:16.
•
• The level of JPEG compression will
determine how much information is lost (this can
be set in most programs that offer jpeg compression).
•
• Jpeg files can be saved with the following
options: "standard", "baseline optimized" and
"progressive".

29. •Algorithm Core of RGB image:•
•
•1) color conversion & down sampling: color
transformation from RGB into the Y Cb Cr space is
used to separate the actual color components from the
brightness Y component.

30. •Algorithm Core of RGB image:
•2) Cosine transform & quantization in frequency
space: The image is divided up to a regular grid of 8
blocks. The frequency spectrum is computed for each
independent block using the discrete cosine
transformation. Next the spectral coefficients of each
block is quantized using quantization table; size of this
table determines the compression ratio.
•
•3) Lossless compression: The quantized spectral
components data stream is again compressed using
lossless method (arithmetic or Huffman) in order to
remove the last redundancy in the data stream.

31. •Merits and Demerits of JPEG formats:
•
• Merits:
Retains up to 16,000,000 colors.
The ability to compress more or less to find a
compromise between file size and image
quality.
Demerits:
Loses information on pixel frequency values
because they may be averaged to the values of
those pixels in its immediately surroundings.
File size larger than gif because of color
information.


32. • JPEG file formats:•
•
•JFIF: What is normally referred to as JPEG is an
instance of “JPEG File Interchange Format”(JFIF) .It
specifies a file format based on the JPEG standard
by defining the remaining necessary elements of the
file format.
•
•EXIF: The exchangeable image file format, Is a
variant of (JFIF) designed for storing image data
originating on digital cameras. It is the practically used
file format by all manufacturers as the standard
format for storing digital images on memory cards.
•

33. •Example
•Original
•1.5 MB
•Lossy
Compression
•92 KB

34. •File Type Comparison

35. •Overview
•Extension •Colour •Compression •Common Uses
•JPG, JPEG •24-bit •Lossy •Photos, web pics
•GIF •8-bit •Lossless •Web graphics – buttons,
icons, etc
•PNG •up to 24-bit •Lossless •Web – replacement for
GIF
•TIF, TIFF •24-bit •Lossless •Professional
•Photos etc

36. •Thank you...