Tham khảo tài liệu 'flash after effects sự kết hợp chuyên nghiệp phần 5', công nghệ thông tin, đồ họa - thiết kế - flash phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | CHAPTER 4 AlphaChannels lmportingaideo into Flashis nothing new. Now thatPlashsuppoasanS-bitaipAa channel new possibilities eHn tseifbrl l h benignett. Alpha chpnneh caovottlyimpaoFetheusesaoperiense in yourvideo-basee Flashapphcations. Whau AreAlppoChattelp .92 AddingCue 2reatingaclnteraetive Video What Are Alpha Channels An RGB image contains three color channels red green and blue. When color image. The alpha channel is a fourthchannelthatcontainsan 8-bitgrayscaleimage. This imagedetermines the transparencyof tanSpixel. pianisbetbme tratsparant aed whlSe pixdlsara oaapaniAnyvalun io yptweenblackandwhife hatannrta i adnarea of tran 2spiyta i arimpgncoatainre4-bits oiyciafosmatlonwith an a4áe H nbanatnel. Figure An alpha channel determines the transparency of each pixel. Whenyou hearthewordsalpha channel rnostFlash des igners think of Adobe Photoshop and PNG files. Those alpha channels are working with still images. Vid a n l oat in arté lohachatenland AttorEffoetrcatcseaUe chis throagUOabia g. .iyinG tanetatelnctaanolarSShekeatinaidpoana rem oantn from rnb tnatlAprimuoaam ylaisyourlanalwaathnrmanooTV. HnlusUanding in front ofpalupot green tcreno lTnetoiattb tareen rpried out and bweashormpp is ph ml rey ting-ranaayuentarea. Figure Keying takes a selected color usually blue or green in video and removes it from the shot. 92 Chapter 4 Alpha Channels In this chapter you will use the Keylight plug-in in After Effects to key out the background in video. The rendered video with an alpha channel will be layered overdiffe rentbackgro und images iKFIash. In addit iontokeying you will also learnaboutsetting uacuepoiatsin Aftersrfentsttatcnhtriegeratnnr events in s stortbbdruotiugagaiphacgaenelviUuo. Locfrtetgechaptet_04border agtSeDVD. negyhiefalrtartaaour hard drive. The folder contains all the files needed to complete the chapter exercises. Keyi
