J

#### Jens Mander

- Jan 1, 1970

- 0

my name is Jens and I am student of the Technical University Berlin. Through

my course of study in microelectronics VHDL design is becoming my favorite

hobby. My other interests are signal processing and compression in general.

Lately I purchased an FPGA Evalution board second-hand (guess where?) and I

am now starting my first "private" implementations. Just to give you a short

intro... ;-)

I am interested in implementing compression algorithms using VHDL on an

FPGA. I want to build a data transmission system that compresses portions of

the incoming data (not the whole data but "frames" of like 800 bytes)

on-the-fly. In my search for a fast (i.e. real-time capable at a "desired"

data rate of - let's say - 300 MHZ?) "universal" compression scheme I came

across the following stepping stones:

- is there any free example code for compression algorithms available in

VHDL to get an overview and a first impression of implementation complexity?

- what would you think are the most promising algorithms for my purpose

(i.e. when statistics and semantics of the input data are unknown), first of

all I thought of delta encoding, sorted RLE, LZ, ....?

- as the input data is unknown the álgorithm must be lossless, reducing

redundancy (if possible), not irrelevancy. what are the theoretical limits

of "universal" compression, not emphazizing one particular statistical

property (like similar by values in succession)?

- what is meant by the keyword "systolic implementations" and "pipeling" in

that particular context? I came across that very often lately

- what if my code gains different compression ratios for consecutive data

portions? surely a FIFO can decouple input and output rate but eventually

the FIFO will underflow?

Thanks for you help + support in advance, any comments, hints and help is

appreciated!

Bye Jens

P.S.: I'm looking for the standard works "Sayood, Khalid: Introduction to

data compression, Academic Press, 199x or 200x" and/or ". Salomon: Data

Compression, Springer-Verlag, New York, 200x". Are there any sources of an

electronic copy (ps, pfd, etc.) or transcriptions?