Session Input Unit-V Session Name : Applications Course Title : CS2403 -Digital Signal Processing Semester : VII Semester Programme Name : B.E Author Name : Mrs.V.GANDHIMATHI Department : ECE Institution Name : VRS College of Engg. & Tech Mobile Number : 9245582632 E-mail : adhihema02@gmail.com Session -1 1. Introduction: Multirate signal processing Suggested Activity: Introduces https://www.google.co.in/?gws_rd=cr&ei=DExFUubNN4WHrgeDkICwBg#q=multirate+signal+processing 2. Decimation and interpolation Suggested Activity: chalk and talk http://users.abo.fi/htoivone/courses/sbappl/asp_chapter2.pdf 3.Conclusion: Recall by keywords a. D b. I c. Up sampling d. Down sampling Multirate Digital Signal Processing Basic Sampling Rate Alteration Devices • Up-sampler - Used to increase the sampling rate by an integer factor • Down-sampler - Used to decrease the sampling rate by an integer factor 1 Copyright © 2001, S. K. Mitra Down-Sampler • Figure below shows explicitly the timedimensions for the down-sampler x[ n] xa ( nT ) Input sampling frequency FT 10 1 T M y[ n] xa ( nMT ) Output sampling frequency F 1 FT' T M T' Copyright © 2001, S. K. Mitra Down-Sampler • Figure below shows the down-sampling by a factor of 3 of a sinusoidal sequence of frequency 0.042 Hz obtained using Program 10_2 Input Sequence 1 0.5 Amplitude Amplitude 0.5 0 -0.5 -1 Output sequence down-sampled by 3 1 0 -0.5 0 10 20 30 Time index n 40 50 -1 0 10 8 20 30 Time index n 40 50 Copyright © 2001, S. K. Mitra Up-Sampler • Figure below shows explicitly the timedimensions for the up-sampler x[ n] xa ( nT ) L y[n] x ( nT / L ), n 0, L , 2 L , a 0 otherwise Input sampling frequency FT 11 1 T Output sampling frequency 1 FT' LFT T' Copyright © 2001, S. K. Mitra Up-Sampler • Figure below shows the up-sampling by a factor of 3 of a sinusoidal sequence with a frequency of 0.12 Hz obtained using Program 10_1 Input Sequence 1 0.5 Amplitude Amplitude 0.5 0 -0.5 -1 4 Output sequence up-sampled by 3 1 0 -0.5 0 10 20 30 Time index n 40 50 -1 0 10 20 30 Time index n 40 50 Copyright © 2001, S. K. Mitra Session -2 1. Introduction: phase shifters Suggested Activity: Discussion http://www.qsl.net/va3iul/Phase_Shifters/Phase_Shifters.pdf 2. Design of phase shifters Suggested Activity: PPT http://en.wikipedia.org/w/index.php?search=phaseshifters&button=&title=Special%3ASearch 3. Conclusion: Rapid fire a. What are phase shifters? b. Give applications of phase shifters? c. Purpose of poly phase structure. Session -3 1. Introduction: digital filters Suggested Activity: Introduces 2. Implementation of digital filter banks Suggested Activity: writing board 3.Sub band coding of speech signals and quadrature mirror filters http://www.compandent.com/ Suggested Activity: PPT Sub-Band Coding Digital signal Analog signal ADC Transmitter channel DAC Analog signal Receiver 4.Conclusion: Questions and answers a. Define sub band coding b. What is digital filter bank? c. Explain quadrature mirror filter. Session -4 1. Introduction: ADC Suggested Activity: Recall by words Words: a. Sampling. b. Sampling theorem c. Quantization d. Continuous time signal http://www.mds.com/products/s042?gclid=CIGf-I-htLoCFWFS4godrDQAJQ 2. Transmultiplexers and AD/DA conversions Suggested Activity: PPT Transmultiplexer FDM to TDM Conversion: SSB Demodulator FDM TDM Signals Decimator O/p1 ADC Signal TDM Signals SSB Demodulator Decimator SSB Demodulator Decimator O/p2 TDM Signals O/p3 TDM-to- FDM Conversion TDM signal Inter polator SSB Modulator Inter polator SSB Modulator DAC FDM signal Inter polator SSB Modulator 3.Speech compression Suggested Activity: PPT 4.Conclusion: Questions a. Define ADC. b. State sampling theorem. c. Give the purpose of transmultiplexers. d. What is speech compression? Session -5 1. Introduction: Adaptive filters Suggested Activity: PPT http://www.eas.asu.edu/~dsp/grad/anand/java/AdaptiveFilter/Zero.html Applications • Parameters – u=input of adaptive filter=output to plant – y=output of adaptive filter – d=desired response=delayed system input – e=d-y=estimation error 2. Wiener filters , LMS and RLS algorithm Suggested Activity: PPT and board •The LMS Algorithm consists of two basic processes – Filtering process • Calculate the output of FIR filter by convolving input and taps • Calculate estimation error by comparing the output to desired signal – Adaptation process • Adjust tap weights based on the estimation error http://www.eas.asu.edu/~dsp/grad/anand/java/ANC/ANC.html 3.Conclusion: Recall and list by key words Words: a. Adaptive filter. b. LMS c. RLS d. FIR e. IIR Session -6 1. Introduction: Musical sound processing www.eetindia.co.in/ Suggested Activity: Analogy 2. Audio processing Suggested Activity: Presentation 3.Conclusion: Recall by writing Sound production Echoes Audio sound Session -7 1. Introduction: Image enhancement http://www.r-s-c-c.org/node/225 Suggested Activity: Discussion & questionnaires a. What is image? b. What are the features of image? 2. Histogram equalization The histogram of a digital image with gray levels in the range [0, L-1] is a discrete function h(rk)=nk , where rk is the kth gray level and nk is the number of pixels in the image having gray level rk. It is common practice to normalize a histogram by dividing each of its values by the total number of pixels in the image, denoted by the product MN. Thus, a normalized histogram is given by h(rk)=nk/MN Suggested Activity: Presentation Let rk, k[0..L-1] be intensity levels and let p(rk) be its normalized histogram function. The intensity transformation function for histogram equalization is k s k T (rk ) ( L 1) p r ( r j ) j 0 L 1 k n j , k 0,1,2,..., L 1 MN j 0 3. Conclusion: Brain storming a. What is image enhancement? b. Define histogram processing. c. What do you mean by equalization? Session -8 1. Introduction: Median Suggested Activity: Introduces and questions 2. Geometric, Harmonic and Contra median: http://www.maxvalue.com/tip104.htm Suggested Activity: Chalk and talk Consecutive terms of a geometric sequence are proportional Consider the geometric sequence with a common factor 10. 4 40 = 40 400 A B D 3. Conclusion: Rapid fire a. Define median. b. What is geometric median? c. Define Harmonic median. d. What do you by contra median? C Session -9 1. Recap: filtering Suggested Activity: Brain storming http://cilab.knu.ac.kr/seminar/Seminar/2010/20101009%20Colour%20Image%20Enhancement%20by% 20Virtual%20Histogram%20Approach.pdf 2. Color Image enhancement 4 of 19 Neighbourhood Operations For each pixel in the origin image, the outcome is written on the same location at the target image. Origin Origin x (x, y) Neighbourhood y Target Image f (x, y) Suggested Activity: PPT 3.DSP processor Suggested –Activity: Demonstration 4. Conclusion: Tit for tat 8 of 19 Smoothing Spatial Filters One of the simplest spatial filtering operations we can perform is a smoothing operation – Simply average all of the pixels in a neighbourhood around a central value – Especially useful 1/ 1/ 1/ 9 9 9 in removing noise Simple from images 1/ 1/ 1/ averaging 9 9 9 – Also useful for filter highlighting gross 1/ 1/ 1/ 9 9 9 detail