Introduction to data (including text) compression
Classes of data compression algorithms
Generally speakingm there are
2 classes
of
data compression
algorithms:
Lossless
data compression
:
When we
uncompress
the
compressed data
, we will obtain an
exact
copy
of the
original data
Examples
of usage of
lossless
data compression
:
Compress
text/binary data files
for
archival purpose
Lossy
data compression
:
When we
uncompress
the
compressed data
, we
do
not
obtain an
exact
copy
of the
original data
Rather
: we obtain an
approxiamte
copy
only .....
Examples
of usage of
lossless
data compression
:
Audio
compression
(
MP3
)
Video
compression
(
MP4
)
Lossless data compression
Lossless data compression
techniques will usually:
gather
information
on the
input file
what is the
most
frequent
pattern (
entrophy
coder
where
can I find some
pattern
in the text (
dictionary
code
)
Then
use
the gathered
information
to
encode
the
input data file
Studying data compression
Data compression
is a
huge area
(data compression is closely related to
information theory
and I am
not
a speciality in that area)
I will basically follow
Goodrich
's treatise in
data compression
and will add some
background
information on the topic to set the context.....