Thesis (MScEng)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Data volumes produced by the next generation of earth observation sensors have increased
greatly in recent years. Sensors are generating more data than can be easily stored
onboard satellites and transmitted to the ground-stations.
There are two strategies for solving this problem. The first is to process all images
onboard the satellite, and only extract the useful or valuable information. The second is
to use a compression algorithm to reduce the data volume.
This thesis looks at both strategies and then focusses on an evaluation of the Embedded
Zerotree Wavelet (EZW) algorithm, a wavelet-based lossy image compression algorithm,
as a solution to reduce the data volumes. Possible hardware implementation strategies
for this algorithm are also explored. Finally, a suggested implementation of the EZW
algorithm is compared with the FlexWave-II system and with JPEG2000. / AFRIKAANSE OPSOMMING: Die data volumes wat deur die nuwe generasie van aardobservasiesensore geproduseer
word, het dramaties vergroot in die laaste paar jaar. Daar word nou meer data geproduseer
as wat aanboord van die satelliet gestoor kan word en meer as wat in die beperkte
kommunikasietyd aan die grondstasie gestuur kan word.
Daar is twee strategiee om hierdie probleem aan te spreek. Eerstens kan beelde aanboord
die satelliet verwerk word om die belangrikste of waardevolste inligting uit te haal en
die res van die data word dan geskrap. Die alternatief is om 'n beeldkompressie-algoritme
te gebruik om die data te verminder.
Hierdie tesis ondersoek hierdie strategieë en fokus dan op 'n evaluasie van die "Embedded
Zerotree Wavelet" -algoritme. Die EZW-algoritme is 'n verlieserige, golfie-gebaseerde
beeldkompressie-algoritme. Moontlike hardeware-implementeringsopsies word ondersoek
en die resultate van een voorgestelde opsie word vergelyk met die FlexWave-II stelsel
asook die nuwe JPEG2000-standaard.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/53264 |
| Date | 12 1900 |
| Creators | Kriegler, Eduard |
| Contributors | Mostert, S., Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 158 p. : ill. |
| Rights | Stellenbosch University |
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