2. BMS2062: IT&T in BioInfo Lecture 2. Digitised images and image compression Kathy Lynch School of Information Management and Systems, Monash University

3. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University2 Digital images “A picture says more than a thousand words”. Does it?

4. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University3 What are digital images?  What are images –TypesTypes –OrientationOrientation –File formatsFile formats –Colour depthColour depth –ResolutionResolution –File sizeFile size  More on images –Obtaining –manipulating

5. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University4 Graphic types  Line art / drawings / clip art  Photographs and photo-realistic images  Animations and simulations  Image Maps

6. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University5 Line art/drawings/clip art/icons

7. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University6 Photographs and photo-realistic images A computer-generated model of Reverse transcriptase and ribonuclese H. (Presscott et al pg376) A photograph of Bacterial colonies on Agar (Presscott et al pg110)

8. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University7 Animations and Simulations  Use of multiple images

9. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University8 Image maps

10. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University9 Orientation  Portrait  Landscape

11. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University10 Colour depth (and palette)  1 bit - 2 colours  4 bit – 16 colours  8 bit – 256 colours  16 bit – 65 thousand  24 bit – 16 million

12. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University11 File formats.bmp (<= 16million colours or 24 bit colour, no compression).jpg (<= 16million colours or 24 bit colour, highly compressed).gif (<= 256 colour or 8 bit colour, moderately compressed)

13. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University12 File size Effected by –width and height of image in the file –colour depth –file format - compression  136KB, 12KB, 11KB

14. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University13 Resolution  Pixels  Screen size - 640 x 480, 800 x 600, 1024 x 768  Often you need to determine the size before you create all your images.  Images lose quality each time they are edited.

15. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University14

16. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University15 Obtaining graphics  Off-the shelf (CDROM or Web page)  Off a Web page  Create your own  Screen shots / dumps or capture  Scan  Digital photography

17. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University16 Off the shelf  Commercial CDROMS  Web http://www.clipart.com; http://www.corbis.com; http://www.arttoday.com; http://www.auslig.gov.au

18. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University17 Off the Web  Right mouse click (Windows) or hold the mouse button down (Mac), then ‘Save Image as’

19. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University18 Create your own Sophisticated software programs

20. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University19 Screen shots or capture  Specialist programs: – Snag It, PaintShopPro  Print screen: –alt/PrntScrn, Ctrl/PrntScrn

21. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University20 Scan anything  photographs or drawings  agar plate  microscopic slides  x-rays  35mm slides  organic objects (eg a leaf and magnifiying glass )  inorganic objects

22. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University21 Digital Photography  Digital cameras – still and video  Single frame from a video

23. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University22 Manipulating images  Tidying up – rubbing out, cropping  Adding text  Colouring in  Resizing (resample)  Changing file format

24. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University23 Manipulating images

25. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University24 Limitations and problems  Mixing everything (fonts, orientation, format, colour depth)  Degradation of images as recompressed or re-edited  Steep learning curve to master some tools  Varying end-user computer configuration

26. BMS2062, Semester 2, 2000. Kathy Lynch, SIMS Monash University25 References  PaintShop download (15MB) http://www.jasc.com/download.html http://www.jasc.com/download.html Earlier version311 is also available (2MB) ftp://www.education.monash.edu.au/pub.wind ows/psp.zip (will need to unzip) ftp://www.education.monash.edu.au/pub.wind ows/psp.zip  Clip art http://www.clipart.com/http://www.clipart.com/