LOW-COST, HIGH-IMPACT VIDEO PRODUCTION TECHNIQUES FOR LABORATORY INSTRUCTIONAL MATERIALS

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1 LOW-COST, HIGH-IMPCT VIEO PROUCTION TECHNIQUES FOR LBORTORY INSTRUCTIONL MTERILS Ewr R. oering 1 bstrct Vieo prouction techniques hve been evelope to prouce lbortory instructionl mterils tht re low cost, both in terms of csh outly n in instructor evelopment time, n yet which chieve high impct in terms of stuent lerning effectiveness. This pper will review the instructionl nees of the stuents tht motivte the specific choice of prouction techniques, n will present ssessment results from clssroom use of the methos. The techniques hve been evelope to support lb-oriente courses tht require stuents to become proficient users of set of C tools. Inex Terms Vieo prouction techniques, multimei tutorils, lbortory instruction. INTROUCTION Multimei technologies continue to ply n incresing role in the clssroom. This growth is fuele in prt by the incresing computtionl horsepower of computer equipment, n in prt by the wiening vilbility of evelopment tools to crete instructionl multimei mterils. Multimei uthoring tools such s Mcromei irector n symetrix Multimei Toolbook II Instructor provie the instructor with high egree of flexibility to merge grphics, text, uio, vieo, n interctivity to crete stn-lone computer-ie lerning tools. However, the typicl evelopment time of hours to prouce one hour of multimei instructionl mteril is prohibitive for the iniviul fculty member [1]. If the multimei moule is focuse more on elivery of course mterils such s vieos of lecture, Power-Point slies, n the like, then the prouction time cn be reuce to bout 2-3 hours per hour of instructionl mteril s in the MNIC [2] n InFusion [3] systems. These systems require certin mount of infrstructure, notbly vieo cmers, vieo-to-igitl conversion equipment, n stuio. Lbortory courses tht require stuents to lern how to use set of C tools require preprtion of tutorils n other reference mteril for the stuents. The visul nture of the C tools mkes vieo nturl choice to cpture n instructor s emonstrtion of the C tool for subsequent n repete viewing by the stuents. Inexpensive softwre exists to cpture computer s screen ctivity n sve it to vieo file, thereby enbling n iniviul instructor to esily n inexpensively crete vieo emonstrtions of C tools in opertion. This pper will present specific prouction techniques to prepre n eliver set of vieo-bse instructionl mterils to support lbortory clss tht requires the stuents to lern severl new C tools. The prouction techniques require only moest investment in softwre. ssessment results from clssroom usge of the mterils will be presente tht show tht the instructor nee not invest lrge mounts of time to mke prouct tht significntly improves the stuent s bility to lern the C tools. PPROCH junior-level igitl systems course requires stuents to become proficient users of reltively lrge number of C tools, specificlly, behviorl simultor, implementtion softwre, n evice progrmming softwre. Moreover, ifferent evice types often require ifferent sets of C tools. For exmple, the lb portion of the igitl system course offere t Rose-Hulmn gives stuents prctice with GLs (generic rry logic), CPLs (complex progrmmble logic evices), n FPGs (fiel-progrmmble gte rrys). Ech of the three evices hs similr esign flow from concept through implementtion to verifie evice, yet the etils iffer since the implementtion softwre is specific to ech evice. In previous offerings of the course, significnt mounts of lbortory time woul be evote to wlk-through emonstrtions of the vrious softwre pckges. Pperbse tutorils crete by the instructors woul then serve s subsequent reference mteril for the stuents. The vntge of this metho is tht the wlk-through emonstrtion gives ll stuents the chnce to wtch over the instructor s shouler, so to spek ( computer projector is use in prctice), n promotes interction between the stuents n instructor. The pper-bse mterils hve the vntges of ny print-bse mei, especilly quick ccess to specific informtion. The isvntge of the existing metho is the reuction of vluble lb time for the stuents to work on their projects, n the lrge mount of time require for the instructor to crete the print-bse tutoril mteril. The ltter issue is primrily ue to the grphicl nture of the C tools. Much of the C tool interction is mouse-bse with grphicl feebck, so the print tutoril typiclly requires mny screen shots n long sequences of menu selections. The pproch escribe here combines the best fetures of the existing methos. Nrrte vieo clips of the 1 Ewr R. oering, eprtment of Electricl n Computer Engineering, Rose-Hulmn Institute of Technology, Terre Hute, IN 47803, E.oering@Rose-Hulmn.Eu 31 st SEE/IEEE Frontiers in Euction Conference F1C-14

2 computer screen serve s the instructor s wlk-through emonstrtion n simultneously become the bsis for the tutoril. The visul nture of the vieo clips cptures the mouse-bse interctions n shows how the C tools shoul respon. The vieo clips cn be replye s mny times s neee, n the vieo plyer controls give the stuent the bility to puse or skip he. Thus, the vieo clips provie the reusbility n ccessibility ssocite with the tritionl pper-bse tutoril. The vieo clips coul be presente simply s set of files with n inex. However, itionl text mteril is necessry to provie orgniztionl structure, so the vieo clips re orgnize into web-bse ocument. In the igitl systems course, the mteril is orgnize by presenting series of options to give the impression tht the stuent is esigning custom esign flow. For exmple, they begin by choosing which evice type they will use (GL, CPL, or FPG). Then they choose the specific venor, then specific prt number, n so on. t the en of the selection process they re presente with flow igrm showing the step-by-step process to move from initil concept to verifie evice. Ech block in the flow igrm is linke to nrrte vieo clip tht provies segment of complete running exmple of the esign flow process. In this wy stuents cn first view the vieo clips in orer to wtch the exmple, then they cn quickly nvigte to specific loctions in the esign flow to rewtch vieo clips s neee. Prouction Tools The prouction tools require to prouce the nrrte vieo clips inclue: Computer: esktop or lptop loe with ll C tool softwre pplictions to be emonstrte. Heset microphone: hns-free microphone is esstentil to permit you to tlk n operte the keybor t the sme time. low-cost microphone cn be obtine for less thn $10. igitl still cmer: Useful to tke pictures of lbortory equipment tht nees to be escribe. Writing tblet: Useful to emulte the effect of writing on whitebor when iscussing the pencil n pper portions of the conceptul esign. I use the Cross ipen ($120). C-ROM burner: The vieo clips require bout one MB/minute, so elivery by C-ROM provies the fstest ccess to the stuents. Screen cpture softwre: I use the HyperCm shrewre ppliction [4] to mke VI-formt vieo clips of screen ctivity. HyperCm inclues the bility to recor soun t the sme time, so you cn tlk while you operte the computer. HyperCm costs bout $30. Web pge uthoring softwre: Microsoft Front Pge or the equivlent simplifies the process of creting the web pges. Web browser Vieo plyer softwre: Current operting systems inclue vieo plyers s stnr pplictions. For exmple, Winows 98 inclues Mei Plyer tht cn re the VI-formt vieo clips prouce by HyperCm. Note tht most of the prouction tools re likely to be vilble lrey, so your itionl costs my be well uner $100. Vieo n uio Cpture Issues The vieo n uio settings of the screen cpture softwre etermine the size of the vieo clip files. The uio smpling frequency ws set to 8kHz to provie resonble qulity soun for voice. Experimenttion showe tht 10 frmes/secon provie sufficient temporl resolution to ccurtely cpture cursor motion n typing. 640x480 screen size with 8 bits/pixel pseuocolor formt ws use uring vieo cpture to provie n imge lrge enough to view the softwre ppliction, yet smll enough so tht the vieo plybck on lrger resolution formt (1280x1024) woul llow the stuent to refer to the vieo while operting the C tool t the sme time. The VI vieo formt use by HyperCm is pixel-ccurte replic of the computer screen. If ech frme were to be sve, the vieo clips woul require 176 MB/minute of isk storge with itionl spce require for the uio. The HyperCm settings were juste to sve key frmes every 100 frmes of incoming vieo. Lossless compression in between the key frmes provie rmtic reuction to 1 MB/minute. Further reuctions woul be necessry to mke prcticl use of streming formts such s RelMei for elivery over low bnwith chnnels. However, the lossy compression use by these streming vieo formts re esigne for nturl vieo such s television n movies. The lossy compression introuces noticeble rtifcts into the computer grphics imges such s schemtic rwing. These compression techniques lso reuce the sptil resolution, so single pixelwith fetures either become blurre or sometimes ispper ltogether. Thus, the VI vieo formt n elivery by C- ROM or locl network ws selecte s compromise between wiespre elivery offere by streming vieo over the web n ccurte repliction of the computer screen imge. prcticl ifficulty ws encountere by the lck of vieo clip eitor. Mking mistke twelve minutes into 20-minute session require strting over t the beginning. I ws not ble to ientify low-cost vieo eitor t the time I prouce the vieos for the course. Sometimes I ws ble to el with unexpecte behvior of the C tool or other glitches on the ir by tlking my wy through the problem n continuing. These problems turne out to be quite interesting to the stuents, since they revele tht the instructor cn experience ifficulty t times s well s the stuents, n the stuents benefite by wtching the content expert troubleshoot n solve the problem. 31 st SEE/IEEE Frontiers in Euction Conference F1C-15

3 I hve recently trie the TechSoft Cmtsi prouct [5] tht offers screen cpture cpbility n vieo clip eiting in single prouct. My initil tests inicte tht Cmtsi cn prouce streming vieo formt with miniml rtifcts on schemtic rwings, so this prouct my be goo lterntive. RESULTS The instructionl mterils were elivere to the stuents vi the cmpus network n by C-ROM, n collectively referre to s PL visor. The stuents were ssigne to review the mterils s prt of their pre-lb preprtions. The stuents were prouctive with the C tools immeitely t the beginning of the lb perio n requeste very little ssistnce with the opertion of the C tools themselves. Stuents woul occsionlly review the vieo clips on n s-neee bsis uring lb, which rise the nee for hephones t times! ssessment t n en-of-qurter survey ws use to ssess the instructionl mterils in more etil. Twenty-two stuents respone to the survey. The survey ws structure s series of sttements to which the stuent woul inicte egree of greement or isgreement. series of openene questions were use to follow up on some of the sttementes. The survey t re summrize below with responses coe s (strongly gree), (gree), (somewht gree), (somewht isgree), (isgree), n (strongly isgree). Note tht some of the percentges o not sum to 10 ue to occsionl nonresponses: Sttement 1: I woul hve preferre to hve the instructor use clss or lb time to present ll the mteril bout the lb softwre pckges inste of using PL visor exclusively % Sttement 3: "PL visor helpe me to feel confient using new softwre tools Sttement 4: "It is importnt to hve complete beginning-to-en exmples. 2 32% 39% Sttement 5: "PL visor shoul hve more polishe ppernce (for exmple, professionllyesigne grphics, professionl nrrtor) to mke it more effective s lerning tool. 49% Sttement 2: I woul hve preferre to hve the instructor present selecte portions of the PL visor mteril in clss or in lb. Sttement 6: Hving the nrrtor slip up occsionlly n then try to correct the problem live is useful teching technique. 31 st SEE/IEEE Frontiers in Euction Conference F1C-16

4 49% Sttement 7: I ws ble to lern new softwre pckges more quickly using the multimei ppoch. Sttement 11: The multimei formt ws more effective thn the tritionl pper hnout formt Sttement 8: Using PL visor ws n efficient wy to lern how to use the vrious softwre pckges (goo use of time) Sttement 9: The orgniztion of the mteril mkes it esy to use s reference t lter time. 38% Sttement 10: The nrrtion of the vieo clips ws well tilore to my lerning nees. nlysis of ssessment t Survey Sttements 1 n 2 explore the nee to continue with some form of in-clss emonstrtions, even when the instructionl mteril is vilble. Hlf of the stuents wnte to use clss time to present ll the mteril, n hlf i not. However, much lrger percentge preferre tht some (not ll) of the mteril shoul be presente. Possibly goo blnce woul be to o n bbrevite wlk-through for the stuent s first contct with the softwre, then rely on the multimei instructionl mterils to fill in the etils. Seventy-five percent of the stuents gree tht the mterils me them feel more confient using new C tools (Sttement 3), n 8 of the stuents gree tht they lerne the softwre more quickly (Sttement 7). ll of the stuents gree tht the complete beginning-to-en exmples were importnt (Sttement 4), inicting tht the instructionl mterils shoul be s complete s possible. lower percentge (62%) gree tht the instructionl mterils were n efficient wy to lern (Sttement 8). n open-ene question on the survey revele tht supplementing the vieos with etile inex n trnscript of the nrrtion woul hve llowe the stuents to more quickly bsorb some of the text -oriente portions of the vieo presenttions, e.g., typing Verilog coe into n eitor. Lck of trnscript ment tht the stuents woul hve to wtch n listen to the entire vieo clip to mke sure they in t miss nything. Sttements 5 n 6 explore the egree to which stuents require perfection in the finishe prouct. Only qurter of the stuents gree tht more polish ws necessry in orer to improve their lerning experience (Sttement 5). Conversely, 74% of the stuents gree tht the occsionl mistke with live trouble-shooting ws useful teching 31 st SEE/IEEE Frontiers in Euction Conference F1C-17

5 technique (Sttement 6). Sttement 10 els with the running commentry tht ccompnies the vieo; 8 of the stuents gree tht the nrrtion ws helpful to their lerning. n open-ene question on the survey inicte tht the stuents strongly prefer hering their instructor s voice s the nrrtion. Overll, 81% of the stuents gree tht the vieo-bse instructionl mterils were more effective thn pperbse tutoril. SUMMRY This pper hs presente specific prouction techniques for vieo-bse instructionl mterils tht cn be use to tech stuents how to use set of C tools in igitl systems lbortory. The techniques re suitble for ny lbortory course tht requires stuents to gin mstery of set of softwre pplictions. The prouction techniques o not require gret el of time or equipment n cn be employe by single instructor. The reltively low time n ollr investment yiels instructionl mterils tht hve been emonstrte to help stuents lern C tools more quickly, thus freeing vluble lbortory time for lerning bout the course mteril. ssessment of the prouction techniques revele tht stuents prefer the instructionl mterils to be prepre by their own instructor, n o not require the results to be totlly polishe in orer to be consiere helpful to their lerning. REFERENCES [1] Hrtmn, J.., eveloping Effective Multimei-Bse Lbortory Moules, Proceeings of the 1999 Frontiers in Euction Conference, IEEE Press, 1999, pp. 13c c3-23. [2] Burleson, W.,. Gnz, n I. Hrris, Euctionl Innovtions in Multimei Systems, Proceeings of the 1999 Frontiers in Euction Conference, IEEE Press, 1999, pp [3] InFusion, [4] HyperCm, [5] Cmtsi, 31 st SEE/IEEE Frontiers in Euction Conference F1C-18