1. Chapter 8
Digital Media

2. Digital Sound Digital Audio Basics Portable Audio Players MIDI Music
Speech Recognition and Synthesis
Chapter 8: Digital Media

3. Digital Audio Basics Sampling a sound wave Chapter 8: Digital Media
Figure 8-1
Chapter 8: Digital Media

4. Digital Audio Basics
Sampling rate refers to number of times per second that a sound is measured
Figure 8-2
Chapter 8: Digital Media

5. Digital Audio Basics
Sound cards are responsible for transforming bits stored in an audio file into music, sound effects, and narrations
Digital signal processor
Figure 8-3
Chapter 8: Digital Media

6. Digital Audio Basics
The most popular digital audio formats include AAC, AIFF, MP3, RealAudio, Wave, and WMA
Audio or media player software allows you to record and play digital audio files
You can embed digital audio files into a Web page
Chapter 8: Digital Media

7. Portable Audio Players
Pocket-sized, battery-powered device that stores digital music
Zune
Digital music is available from a wide variety of sources
Formats include AAC, MP3, WAV, and AIFF
Figure 8-5
Chapter 8: Digital Media

8. MIDI Music
MIDI (Musical Instrument Digital Interface) specifies a standard way to store music data for synthesizers, electronic MIDI instruments, and computers
MIDI-capable sound cards contain a wavetable
Set of prerecorded musical instrument sounds
Does not produce high-quality vocals
Does not have full resonance of “real” sound
Chapter 8: Digital Media

9. MIDI Music
MIDI music tends not to have the full resonance of digital audio.
Figure 8-7
Chapter 8: Digital Media

10. MIDI Music Music composition software
provides tools for entering notes, specifying instruments, printing sheet music, and saving compositions in formats
such as MIDI.
Figure 8-8
Chapter 8: Digital Media

11. Speech Recognition and Synthesis
Speech synthesis is the process by which machines produce sound resembling spoken words
Text-to-speech software
Speech recognition refers to the ability of a machine to understand spoken words
Speech recognition software
Chapter 8: Digital Media

12. Speech Recognition and Synthesis
Figure 8-10
Chapter 8: Digital Media

13. Bitmap Graphics Bitmap Basics Scanners and Cameras Image Resolution
Color Depth and Palettes
Image Compression
Bitmap Graphics Formats
Chapter 8: Digital Media

14. Bitmap Graphics Composed of a grid of dots
Color of each dot is stored as a binary number
Figure 8-11
Chapter 8: Digital Media

15. Scanners and Cameras To scan an image, turn on the
scanner and start your scanner
software. Place the image face
down on the scanner glass, and
use the scanner software to initiate the scan. The scanned image is saved in RAM and can then be saved on your computer’s hard disk.
Figure 8-12
Chapter 8: Digital Media

16. Scanners and Cameras
The controls for a digital camera are very similar to those for an analog, or film, camera. To take a photo, simply point and shoot.
Figure 8-13
Chapter 8: Digital Media

17. Scanners and Cameras Digital cameras use storage medium
Solid state storage
Transfer images using:
Card readers
Direct cable transfer
Infrared port
Media transfer
Docking station
Figures 8-14 and 8-15
Chapter 8: Digital Media

18. Scanners and Cameras
Graphics software is used to modify or edit bitmap graphics
Modify individual pixels to
Retouch photographs
Wipe out red eye
Erase rabbit ears
Require a bit of storage space
Figure 8-16
Chapter 8: Digital Media

19. Image Resolution
Expressed as the number of horizontal and vertical pixels
Higher resolutions contain more data (larger file size) and are higher quality
Bitmaps do not have a fixed physical size
Figure 8-17
Chapter 8: Digital Media

20. Image Resolution File size of bitmaps can be reduced by cropping
Bitmaps are resolution dependent
Figure 8-18
Chapter 8: Digital Media

21. Image Resolution
When you increase the resolution of a bitmap, pixel interpolation may occur
Some images may appear pixilated
Figure 8-19
Chapter 8: Digital Media

22. Color Depth and Palettes
Color depth is the number of colors available for use in an image
Monochrome bitmap
Increasing color depth increases file size
True Color bitmap (24-bit bitmap)
32-bit bitmap
Color palettes are used to control color depth
Grayscale palette
System palette
Web palette
Chapter 8: Digital Media

23. Color Depth and Palettes
Figures 8-21 and 8-23
Chapter 8: Digital Media

24. Image Compression
Any technique that recodes data in an image file so it contains fewer bits
Lossless compression
Lossy compression
Run-length encoding
File compression utility
Figure 8-25
Chapter 8: Digital Media

25. Image Compression
File compression utilities, such as open source 7-Zip, zip one or more files into a new compressed file with a .zip extension.
Figure 8-26
Chapter 8: Digital Media

26. Bitmap Graphic Formats
Figure 8-29
Chapter 8: Digital Media

27. Vector and 3-D Graphics Vector Graphics Basics
Vector-to-Bitmap Conversion
Vector Graphics on the Web
3-D Graphics
Chapter 8: Digital Media

28. Vector Graphic Basics Contain instructions for re-creating a picture
Figure 8-30
Chapter 8: Digital Media

29. Vector Graphic Basics Vector graphics resize better than bitmaps
Vector graphics usually require less storage space than bitmaps
Vector graphics are not usually as realistic as bitmap images
It is easier to edit an object in a vector graphic than an object in a bitmap graphic
Chapter 8: Digital Media

30. Vector Graphic Basics
Figure 8-33
Chapter 8: Digital Media

31. Vector-to-Bitmap Conversion
Rasterization superimposes a grid over a vector image and determines the color for each pixel
Tracing software locates the edges of objects in a bitmap image and converts the resulting shapes into vector graphic objects
Figure 8-35
Chapter 8: Digital Media

32. Vector Graphics on the Web
SVG (Scalable Vector Graphics) and Flash are vector graphic formats for the Web
Flash
Animated GIF
Advantages of using vector graphics
Consistent quality
Searchable
Compact file size
Figure 8-36
Chapter 8: Digital Media

33. 3-D Graphics Stored as a set of instructions
Contain locations and lengths of lines forming a wireframe
Rendering covers a wireframe with surface color and texture
Ray tracing adds light and shadows to a 3-D image
Chapter 8: Digital Media

34. 3-D Graphics
3-D graphics are based on a wireframe, which can be rendered into a bitmap image that looks three-dimensional.
Figure 8-39
Chapter 8: Digital Media

35. Digital Video Digital Video Basics Producing Video Footage
Video Transfer
Video Editing
Video Output
Desktop, PDA, and Web Video
DVD-Video
Chapter 8: Digital Media

36. Digital Video Basics
Uses bits to store color and brightness data for each video frame
Different kinds of digital videos:
Desktop video
Web-based video
DVD-video
PDA video
Figure 8-41
Chapter 8: Digital Media

37. Digital Video Basics
Figure 8-42
Chapter 8: Digital Media

38. Producing Video Footage
Use digital or analog video camera to shoot video footage
Digital video cameras store footage as a series of bits
Analog video cameras store video signals as a continuous track of magnetic patterns
Videoconferencing cameras (Web cam) attach directly to a computer
Figure 8-43
Chapter 8: Digital Media

39. Producing Video Footage
Figure 8-44
Chapter 8: Digital Media

40. Video Transfer
Transfer video footage by connecting a cable between a video source and computer
Video capture converts analog video signals into digital format
Figure 8-45
Chapter 8: Digital Media

41. Video Transfer Video capture software controls the transfer process
Figure 8-47
Chapter 8: Digital Media

42. Video Transfer Raw, uncompressed formats are ideal for editing
Video capture software can:
Decrease video display size
Reduce the frame rate
Compress data
Chapter 8: Digital Media

43. Video Editing Linear editing Requires at least two VCRs
Nonlinear editing
Requires a computer hard disk and video editing software
Figure 8-48
Chapter 8: Digital Media

44. Video Output
Figure 8-49
Chapter 8: Digital Media

45. Video Output
Figure 8-50
Chapter 8: Digital Media

46. Desktop, PDA, and Web Video
Desktop videos are usually displayed on a computer screen
Some PDAs and smartphones can be configured to play digital video
Web-based videos
Streaming video
Figure 8-51
Chapter 8: Digital Media

47. Desktop, PDA, and Web Video
You can add external or internet videos to a Web page
Internet connection speed affects Web videos
Web video formats include Flash Video, MPEG4, QuickTime Movie, Windows Movie, and RealMedia
Figure 8-52
Chapter 8: Digital Media

48. DVD-Video Incorporate digital videos onto DVDs with interactive menus
DVD authoring software
Figure 8-53
Chapter 8: Digital Media

49. DVD-Video With advance planning, menus are easy to create
Output video in DVD-video format
A DVD image is a prototype of your DVD
Stored on your computer’s hard disk
Thoroughly test DVD on your computer before you burn it
Recordable vs. rewritable DVDs
Chapter 8: Digital Media