TRANSFORM CODING Presented By : Nancy B.C.A. Final
CONTENTS • What is Transform Coding ? • Why it is needed ? • How it is carried out ? • Features
TRANSFORM CODING = TRANSFORMATION + CODING
TRANSFORMATION Converting a bundle of data into an alternate form, which is more convenient for some purpose.
CODING Coding means a process which is carried out to get some specific output.
The purpose of Transformation coding is to convert the data (images/videos) into a form where they could be easily compressed.
Bits in array of pixels A B C D
Original Format Pixels Bits used to store them A 8 B 8 C 8 D 8 Total 32
In Transformation process Transform Inverse Transform X0 = A A = X0 X1 = B - A B = X1 + X0 X2 = C - A C = X2 + X0 X3 = D - A D = X3 + X0
After Transformation Pixels Bits used to store them A = X0 8 B = X1 + X0 4 C = X2 + X0 4 D = X3 + X0 4 Total 20
FEATURES • It’s a LOSSY COMPRESSION technique. • Generally used for converting natural data such as audio signals and photographic images. • Removes REDUNDANCY from the data. • Lowers the BANDWIDTH of data. • Forms an image with fewer colors. • JPEG(Joint Photography Experts Group) is an example of Transform Coding.
THANK YOU

Transform coding