190 likes | 301 Views
Screen Images. dots call pixels each pixel is a colour. colours = bit sequences. more bits per pixel allow more colours. bit depth / colour depth. Bit Mapped Graphics. record colour to light each pixel. 8 bit : 256 colours, or shades of grey.
E N D
Screen Images • dots call pixels • each pixel is a colour. • colours = bit sequences. • more bits per pixel allow more colours. • bit depth / colour depth.
Bit Mapped Graphics • record colour to light each pixel. • 8 bit : 256 colours, or shades of grey. • 24 or 32 bits for photorealistic colour (millions for colours). • also called raster graphics. • bmp, tiff, jpg, gif, png. • Images from scanners, digital cameras.
Resolution • dots per inch. • 96 dpi looks good on the monitor. • printed images need more detail (higher resolution). • jaggies – low resolution. • 300 dpi : high quality printed image. • take up a lot of memory, can’t display every pixel at normal magnification.
Paint Programs • model an artists tools. • more sophisticated = more tools. • palette : selection of tools available. • not limited like the physical world.
Bit Mapped Graphics • created by paint programs, capture them using a digital camera or scanner. • photo-editing software to edit the images : • good : change lighting, reduce red-eye, cut people out. • bad : create images that aren’t true, but are incriminating.
Managing Photos • photo management software : iPhoto! PictureIt. • software often comes with your digital camera. • indexing and achieving digital images. • digital prints.
Object Oriented Graphics • clip art, line drawings, diagrams. • infinitively scalable. • not as much memory or storage. • can’t capture photo realistic detail. • instructions to draw the image. • postscript language, pdf files. • true-type fonts.
Data Compression • files can be large. • storage & network bandwidth. • lossy & loseless compression. • dictionary, more compact representation.
3D Modeling • virtual objects • rotate & explore • movies, commercials, simulated environments.
CAD / CAM CAD - Computer Aided Design • designers, engineers, architects. • designing products using a computer. • used to be just drafting tools, now include modeling tools : incorporate object properties like weight/mass or centre of gravity in the model.
CAD / CAM Computer Aided Manufacturing • computer guides the manufacturing. • program to create the product generated from the model.
Presentation Software • features to aid in lectures, talks, presentations, sales pitches, etc. • templates – layout & design to get you started. • bulleted lists, graphics, multimedia aspects (sounds, animations). • output – LCD projector, computer display, web, handouts, etc.
Animation • still frames shown in rapid succession: • animated GIFs • tweening / key frames. • algorithms for texture, lighting, etc. • vector graphics animation: • use objects like puppets • record events & interactions. • Macromedia Flash