digital image processing
- 2. ERROR FREE COMPRESSION
Error free compression is the only acceptable means of data
reduction.
One such application is the archival of medical or business
documents.
Need for error free compression is motivated by the intended
use or nature of the images under consideration.
- 3. There types in error free compression
Variable-length coding
Huffman coding
Arithmetic coding
Variable-length coding
Error-free image compression is to reduce
only coding redundancy.
coding redundancy normally is present in
any natural binary encoding of the gray level in an image.
- 4. HUFFMAN CODING
Coding the symbol of an information source individually.
Huffman coding yields the smallest possible number of
code symbols per sources symbol.
The constraint that the source symbol be coded one at a
time.
- 6. ARITHMETIC CODING
Arithmetic coding generates non-block codes.
A one-to-one correspondence between source symbols and
code words does not exist
Sequence of source symbols is assigned a single arithmetic
code word.
- 8. LOSSY COMPRESSION
Lossy compression encoding is based on the concept of
compromising the accuracy
The reconstructed image in exchange for increased
compression.
The resulting distortion can be tolerated
The increase in compression can be significant.
- 9. LOSSY PREDICTIVE CODING
Add a quantizer to the model introduced examine the
resulting trade-off between reconstruction accuracy and
compression performance.
Lossy predictive coding model
A)encoder
B)decoder
- 11. DELTA MODULATION
Delta modulation(DM) is a simple but well-known form of
lossy predictive coding in which the predictor and quantizer
are defined
- 14. TRANSFORM CODING
Transform coding a reversible, linear transform is used to
map the image into a set of transform coefficients.
Which are then quantized and coded.
- 16. Performs four relatively straightforward operations
DECOMPOSITION
TRANSFORMATION
QUANTIZATION
CODING
An NXN input of image first is subdivided into subimages
of size nXn.
Which are then transformed to generate(N/n)2 sub image
transform arrays.