G0Q55A – Multimedia: modelleren en programmeren 2007/2008 Martin Wolpers & Erik Duval 09 November

 Group presentation groups  Some secrets of images  Java & Java Media Framework  Java Assignment G0Q55A – Multimedia: modelleren en programmeren 2007/20082

 Group 5 Group 5  Jan Sebrechts  Sébastien Devynck  Pieter Gevers  Kim Gressens  Iwein Vranckx  Group 6 Group 6  Jelle Wardenier  Laurens Serneels  Stijn Adriaensens  Tim Boven G0Q55A – Multimedia: modelleren en programmeren 2007/20083

4  Digital images vs. Analog images  Here  Digital representations of images  No video!  No recording!  No capturing! Presentation based on Fundamentals of Multimedia, Li&Drew, Prentice Hall 2003

G0Q55A – Multimedia: modelleren en programmeren 2007/20085  Color models (RGB vs. CYM)  Gray Images  1-bit  Gray scale  Color images (GIF)  Color images compression (JPG)

G0Q55A – Multimedia: modelleren en programmeren 2007/20086  RGB: Red – Green – Blue  For monitors: colors add  CMY: Cyan – Magenta – Yellow  For printing: colors subtract

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8 C1R M =1 -G Y1B R1C G =1 -M B1Y

G0Q55A – Multimedia: modelleren en programmeren 2007/20089  Color ~ (Voltage of color electron gun) gamma => not enough light with low voltages

G0Q55A – Multimedia: modelleren en programmeren 2007/  1-bit: white or black  640x480~37,5 kByte  Pixel??

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G0Q55A – Multimedia: modelleren en programmeren 2007/ Graphic from

G0Q55A – Multimedia: modelleren en programmeren 2007/  1 pixel = 1 gray value  1 gray value = 1 byte  Bitmap = cube with dimension image size x 8 bit  Size 640x480x1Byte = 300kByte  E.g. bmp

G0Q55A – Multimedia: modelleren en programmeren 2007/  Transform 1 pixel to larger pattern  Used for 1-bit printers  Example  2x2 dither matrix: transform [0..255] -> [0..4]  0:0 1: [1..63], 2:[ ], 3:[ ], 4:[ ]  Better ideas?  Size: 4x 640x480x1Byte

G0Q55A – Multimedia: modelleren en programmeren 2007/  24-bit color images  3 channels, 1 Byte per channel  256x256x256 colors (~16M) (more later)  Size: 640x480x24bit ~ 900kByte  32-bit color images  24-bit images + special effects channel (1 Byte)  8-bit color images  No direct color information  Color look-up index

G0Q55A – Multimedia: modelleren en programmeren 2007/ kByte300kByte

G0Q55A – Multimedia: modelleren en programmeren 2007/  1byte index into color palette (256 colors)  Size: 1bytex640x480 ~ 300kByte

G0Q55A – Multimedia: modelleren en programmeren 2007/ Bitmaps and Container  TIFF  WMF  8-bit GIF  PNG  JPEG  EXIF Vector formats  PS and PDF  SVG

G0Q55A – Multimedia: modelleren en programmeren 2007/  TIFF : stands for Tagged Image File Format.  Attachment of additional information (referred to as “tags”)  Flexibility  Most important tag format signifier: type of compression etc.  TIFF can store many different types of image 1-bit, grayscale, 8-bit color, 24-bit RGB, etc.  TIFF is lossless format but JPEG compression possible

G0Q55A – Multimedia: modelleren en programmeren 2007/  Microsoft Windows: WMF native vector file format:  Consist of a collection of GDI (Graphics Device Interface) function calls, also native to the Window environment.  “played” a file (typically using the Windows PlayMetaFile() function) == render graphics  Device-independent and unlimited in size.

G0Q55A – Multimedia: modelleren en programmeren 2007/  Graphics Interchange Format  GIF87a (original)  GIF89a (extension for simple animations)  8-bit color images  Interlacing

G0Q55A – Multimedia: modelleren en programmeren 2007/ GIF Signatur Screen Descriptor Global Color Map Image Descriptor Local Color Map Raster Area GIF Terminator Repeat n times

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G0Q55A – Multimedia: modelleren en programmeren 2007/ Length: 2^(Pixel+1)

G0Q55A – Multimedia: modelleren en programmeren 2007/  PNG format : standing for Portable Network Graphics  → meant to supersede the GIF standard, and extends it in important ways.  Special features of PNG files include:  Support for up to 48 bits of color information — a large increase.  contain gamma-correction and alpha-channel information  Progressive display (2-dimensional fashion in seven passes through each 8 × 8 block)

G0Q55A – Multimedia: modelleren en programmeren 2007/  JPEG  Image compression standard (Joint Photographic Experts Group) 1992  JPEG is a lossy image compression method  transform coding method using the DCT ( Discrete Cosine Transform ).  An image = F(i, j) in the spatial domain.  2D DCT yields a frequency response which is a function F ( u, v ) in the spatial frequency domain

G0Q55A – Multimedia: modelleren en programmeren 2007/  Observation 1  Intensity does not change widely in small areas  Observation 2  High spatial frequency less noticed by humans  Observation 3  Visual acuity (accuracy in distinguishing closely spaced lines) is much greater for gray (“black and white”) than for color.

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G0Q55A – Multimedia: modelleren en programmeren 2007/ Original20%5%

G0Q55A – Multimedia: modelleren en programmeren 2007/  EXIF (Exchange Image File) used for digital cameras:  Compressed EXIF files use the baseline JPEG format.  Tags (many more than in TIFF) facilitate higher quality printing, more information  about the camera  picture-taking conditions (flash, exposure, light source, white balance, type of scene, etc.)  Specification of file format for audio that accompanies digital images.

G0Q55A – Multimedia: modelleren en programmeren 2007/  Images made up of simple mathematically describable geometrical forms  E.g. lines, polygons, circles, bezier curves, etc.  Combined and transformed to form complex objects  File formats  PS and PDF  SVG: xml based, WWW consortium  WMF: windows  Text, too: True Type fonts

G0Q55A – Multimedia: modelleren en programmeren 2007/  Layout and Content are true-copy enabled!  Postscript – language for typesetting  Vector-based picture language  Postscript includes text as well as vector/structured graphics.  GL bit-mapped images included in output  Encapsulated Postscript (eps) files add additional information for inclusion  no compression (stored as ASCII)  Portable Document format (PDF)  LZW compression  Without images (compression ratio, 2:1 or 3:1)

G0Q55A – Multimedia: modelleren en programmeren 2007/ Graphic from

G0Q55A – Multimedia: modelleren en programmeren 2007/  Filters frames/fip-Morpholo.html frames/fip-Morpholo.html  Image processing at TU Delft frames/fip.html frames/fip.html

Java Tutorial  Java Media Framework  G0Q55A – Multimedia: modelleren en programmeren 2007/200835

Implementation of your CO2 calculator in Java Follow strictly (!!)  Your Storyboard  Your Flow Chart /State Diagram  Your Layout  Your Timeline Running Applet (!) including source code documentation Deadline: G0Q55A – Multimedia: modelleren en programmeren 2007/200836

 Applet works; name restrictions  Programming Syle: readalbe, structured, layout, naming,...  Document differences to flash, smil, etc. wnd why!  Say who did what for how long  Used tools G0Q55A – Multimedia: modelleren en programmeren 2007/200837