Transcription
Computação Visual e Multimédia10504: Mestrado em Engenharia InformáticaChap. 1 — Digital Signal Processing: BasicsModule Introduction
http://en.wikipedia.org/wiki/FrequencyWhat is a signal?Chapter 1: Digital Signal Processing: BasicsSinusoidal waves of various frequencies; the bottom waves have higher frequenciesthan those above. The horizontal axis represents time.
Chapter 1: Digital Signal Processing: lAmplitude, wavelength, frequency, velocity, period
Analogical vs. Digital SignalsChapter 1: Digital Signal Processing: Basics
http://en.wikibooks.org/wiki/Digital Signal Processing/Sampling and ia/node149.htmlSamplingChapter 1: Digital Signal Processing: .html
Chapter 1: Digital Signal Processing: BasicsNyquist’s sampling theoremf (t) f (t) s(t) s(t) δ (t nt tmln t0 f s (t) f s (t) f (t)s(t) f (t) δ (t nt 0 )n
lExample: playing piano on telephone?Chapter 1: Digital Signal Processing: BasicsHumans hear frequencies from 20Hz up to 20kHz.
Chapter 1: Digital Signal Processing: 49.htmlExample: more about aliasing in music
Chapter 1: Digital Signal Processing: gAliasingAliasing example of the A letter in Times NewRoman. Left: aliased image, right: antialiased image.
QuantizationChapter 1: Digital Signal Processing: Basicsanalog gsampled signalquantized signal
Quantization levelsChapter 1: Digital Signal Processing: Basicsanalog gsampled signalquantized signal
Chapter 1: Digital Signal Processing: Basics
nal Asignal SNR Pnoise Anoise Psignal – power of signalPnoise – power of noisehttp://en.wikipedia.org/wiki/Signal-to-noise ratioSignal-to-noise ratio (SNR)Chapter 1: Digital Signal Processing: Basics
Chapter 1: Digital Signal Processing: BasicsNoise gh(x, y) d(x, y) f (x, y) n(x, y) convolution
http://en.wikipedia.org/wiki/Aliasing#FoldingNoise typeshttp://en.wikipedia.org/wiki/White noiseChapter 1: Digital Signal Processing: Basics
What is DSP? Digital Signal ProcessingChapter 1: Digital Signal Processing: BasicsAnalysing and changing information which is measured asdiscrete sequences of numbers
Chapter 1: Digital Signal Processing: gDSP DigitalSignalAnalogSignalreconstruction
Main limitations of DSPChapter 1: Digital Signal Processing: gSampling signals that are analog in nature leads to Loss of Information!
http://www-sigproc.eng.cam.ac.uk/ op205/3F3 1 Introduction to ngChapter 1: Digital Signal Processing: BasicsAdvantages of Digital over Analog Signal Processing
DSP Applications: Radar and SonarChapter 1: Digital Signal Processing: Basics
DSP Applications: Biomedical DevicesPerson wearingelectrodes for ECGChapter 1: Digital Signal Processing: BasicsPerson wearingelectrodes for EEG
DSP Applications: SpeechChapter 1: Digital Signal Processing: Basics
DSP Applications: MusicChapter 1: Digital Signal Processing: Basics
DSP Applications: CommunicationsChapter 1: Digital Signal Processing: Basics
DSP Applications: Image ProcessingChapter 1: Digital Signal Processing: Basics
SummaryChapter 1: Digital Signal Processing: Basics
Computação Visual e Multimédia 10504: Mestrado em Engenharia Informática Chap. 1 — Digital Signal Processing: Basics! Chapter 1: Digital Signal Processing: Basics! What is a signal?! Sinusoidal waves of various frequencies; the bottom waves have higher frequencies than those above. The horizontal axis represents time.!
