Microsoft PowerPoint - D07_TV&Display_note.ppt

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민채 학
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1 Digital Image Processing 7. TV and Display Computer Engineering, Sejong University Analog (NTSC) TV 와 Digital TV 의기능비교 구분 아날로그 TV (NTSC) SDTV 디지털 TV(ATSC) HDTV 채널 (6 MHz ) 1 채널 3 4 채널 1 채널 음성다중 2 채널 ( 스트레오 ) 5.1 채널 5.1 채널 부가서비스 가능 ( 단순 ) 가능 ( 다양 ) 가능 ( 다양 ) 화면비 4 : 3 4 : 3 / 16 : 9 16 : 9 주사선수 525 i ( 저화질 ) 480 x 704 i/p 480 x 640 i/p ( 중화질 ) 1080 x 1920 i/p 720 x 1280 p ( 고화질 ) 양방향성 단방향 양방향 양방향 수상기가격 낮음 중간 높음 변조방식 VSB 8-VSB 8-VSB 외부잡음 약함 강함 강함 송신전력 높음 낮음 낮음 2/40

2 디지털방송방식비교 제작 편집 송출 수신모든단계에서필요한영상, 음성등의신호를디지털신호로변환하고, 이를압축하여보내는방식 구분전송방식 ( 변조방식 ) 영상신호압축방식음성신호압축방식다중화방식 미국방식 (ATSC) 8-VSB MPEG-2 Dolby AC-3 MPEG-2 유럽방식 (DVB-T) COFDM MPEG-2 MPEG-2 MPEG-2 ATSC : Advanced Television Systems Committee DVB : Digital Video Broadcasting VSB : vestigial sideband transmission COFDM: coded orthogonal frequency division multiplexing 3/40 아날로그방송방식비교 NTSC : national television system committee - 미국텔레비전시스템위원회 (National Television System Committee) 에의해미국의통일방식으로서인정된방송방식. 북중미및한국, 일본등에서사용. 525line 30 frame/sec Interlaced scan. PAL : phase alternation by line system - 색상및포화도에관한정보는 90 o 의위상차를갖고변조되어송신되며, 각각의변조신호는스캔라인별로위상을 180 o 전환하여송신. 625line 25 frame/sec Interlaced scan. SECAM : sequential couleur a memoire color television system - 주사선마다 2개의색차신호를순차적으로교체하면서색부반송파를주파수변조하여휘도신호에중첩시켜전송하는컬러텔레비전방식. 625line 25 frame/sec Interlaced scan. 4/40

3 지역별아날로그방송방식채택현황 5/40 Interlaced Raster Scan ( 비월주사방식 ) NTSC 방송방식의이해 6/40

4 Color Space 1. RGB Color Space (used in color computer graphics and color television) 2. YUV Color Space - used in the PAL system Y = 0.299R' G' B' U = 0.147R' 0.289G' B' = 0.492( B' Y ) V = 0.615R' 0.515G' 0.100B' = 0.877( R' Y ) For digital RGB values with a range of 0 to 255, Y: 0~255, U: -112~112, V: -157~ YIQ Color Space (derived from the YUV color space) - used in the NTSC system Y = 0.299R' G' B' I = 0.596R' 0.275G' 0.321B' = V cos33 U sin 33 = 0.736( R' Y ) 0.268( B' Y ) Q = 0.212R' 0.523G' B' = V sin 33 + U cos33 = 0.478( R' Y ) ( B' Y ) 7/40 Color Space 4. YPbPr Color Space (scaled, and offset analog version of the YUV color space) Y = 0.299R' G' B' Pb = 0.116R' 0.384G' B' = ( B' Y ) /1.826 Pr = 0.500R' 0.445G' 0.055B' = ( R' Y ) / YCbCr Color Space (scaled, and offset digital version of the YUV color space) Y = 0.299R' G' B' Cb = ( 44 / 256) R' (87 / 256) G' + (131/ 256) B' = 0.564( B' Y ) Cr = ( 131/ 256) R' (110 / 256) G' (21/ 256) B' = 0.713( R' Y ) For digital RGB values with 0 to 255, Y:16~235, Cb:16~240, Cr:16~240 with 128 equal to zero. 6. Brightness, Hue and Saturation Brightness: from black to white. Hue: the wavelength of the color. the term used for the base color - red,green,yellow,etc. Saturation: the less saturated the color is adding white to the pure color. 8/40

HSI 좌표계 Hue, Saturation, Intensity (brightness) 로 color 를표현 Brightness (intensity) Saturation Hue 9/40 Composite color signal RGB 신호를전송하는데 1 색신호당 4MHz 이상의대역이필요 RGB 신호를 YIQ

5 HSI 좌표계 Hue, Saturation, Intensity (brightness) 로 color 를표현 Brightness (intensity) Saturation Hue 9/40 Composite color signal RGB 신호를전송하는데 1 색신호당 4MHz 이상의대역이필요 RGB 신호를 YIQ 신호등으로색좌표변환한후 Y 신호에 IQ 신호를적절히합성하여하나의 composite color signal( 복합색신호 ) 로만들어서 6MHz 의 TV 대역폭으로전송 Vertical blanking signal( 수직동기신호 ), Horizontal blanking signal( 수평동기신호 ) 도같이실어서전송함 10/40

6 525/60 monochrome video spectrum Video Carrier Audio Carrier 0.75 MHz 1.25MHz 4.2MHz 4.5MHz 6MHz Frame : 525 lines : 1/30 sec Field : lines : 1/60 sec Horizontal scan frequency 262.5x60 = 15750Hz DC component 1st Line frequency 2nd Line frequency 60Hz (Vertical field repetition frequency) 266th Line frequency Hz 31500Hz MHz 30Hz (Vertical frame repetition frequency) 11/40 Significant amplitude and timing values 40 Lines 10.7 usec Total Line Duration usec Active Line Duration usec Vertical Blanking Total Frame 525 Lines Active Frame 485 Lines Horizontal Blanking Black Area White Area White Level 100IRE (714.3mV) Black Level 7.5IRE (53.5mV) Blanking Level 0IRE (0mV) SyncTip Level -40IRE (-285.7mV) Video Information Sync Information Peak to Peak amplitude (1V) 12/40

7 Vertical sync information Start of Field 1 3H Vertical Blanking Interval 3H 3H Vertical Blanking Interval Start of Field 1 Pre-equalizing Pulse interval Vertical Sync Pulse interval Post-equalizing Pulse interval 1.5us H H: nominal line period us Vertical blanking interval:1-20 lines Pre-equalizing Pulse H 0.5H 525 lines Active Video Field: lines Vertical blanking interval: lines 2.3us Pre-equalizing Pulse 4.7us Vertical Serration Active Video Field: lines 13/40 NTSC Spectral Interleaving and Video Spectrum Y I,Q Y I,Q Y Fh/2 Fh/2 F Fh = kHz NTSC horizontal frequency interleave principle (Note that 227.5Fh = Fsc) U Y V U Y V F 29.97Hz 59.94Hz Field repetition frequency 29.97Hz Frame repetition frequency Fh/4 Fh/2 Fh = kHz PAL horizontal frequency interleave principle 14/40

8 NTSC Composite Video Signal for 75% amplitude, 100% Saturation EIA Color Bars W Y C G M R B Blk White level 100 IRE 3.58MHz Color Burst (9Cycles) 40 IRE 20 IRE 20 IRE Black level Blank level Burst Locked Sinewave Sync level 19Cyc 9Cyc Blank level Luminance level Phase=Hue Color Saturation Subcarrier is suppressed in the white, black and gray color. 15/40 Video Color Bar Signals EIA Color Bars White,yellow,green,magenta,red, and blue SMPTE Color Bars EIA Color Bars(first 2/3 of the field) + Reverse Blue Bars(next 1/12 of the field) + PLUGE(remainder of the field) PLUGE is a visual reference, with one area blacker than black, one area at black, and one area lighter than black. Y Color Bars Cross 16/40

9 Chroma subsampling Providing full luma detail is maintained, vision s poor color acuity enables color detail to be reduced by subsampling YCbCr 4:4:4 YCbCr 4:2:2 YCbCr 4:2:0 : Y : Cb : Cr 17/40 The time-division multiplexing of video data Line4 Field 1 (F=0) ODD Blanking Optional Blanking Field 1 Active video Line1(V=1) Line10(V=X) Line20(V=0) Digital blanking Digital active line 1440 words(0-1439) 276words ( ) Total line 1716 words(0-1715) H Control Signal Line266 Field 2 (F=1) EVEN Blanking Optional Blanking Field 2 Active video Line264(V=0) Line273(V=X) Line283(V=0) Time-division multiplexed 27MHz bit-parallel data Cosited samples Isolated luminance samples Cosited samples Cb1 Y1 Cr1 Y2 Cb3 Y3 Cr3 Y4 Cosited samples Cb5 Y5 Cr5 Line3 H=1 EAV H=0 SAV Line525(V=0) LineNumber F V H(EAV) H(SAV) 1_ _ _ _ _ _ /40

10 4:2:2 Digital Component Video Sample data at Oh instant Luminance data Y Chrominance data Cb Chrominance data Cr Multiplexed data Cb359 Y718 Cr359 Y719 Cb360 Y720 Cr360 Y721 Cb368 Y736 Cr368 Y855 Cb428 Y856 Cr428 Y857 Cb0 Y0 Cr0 Replaced by TRS Replaced by TRS Multiplexed data with EAV and SAV Cb359 Y718 Cr359 Y719 Cb368 Y736 Cr368 Y855 Cb0 Y0 Cr0 Word No EAV Timing reference signals SAV 19/40 Closed Captioning IRE Units Blanking level Program color burst us (0.20H) 7 cycles of MHz (clock run-in) S T A R T D0 - D6 P A R I T Y us (0.53H) D0 - D6 Two (ch.7-bit+parity 1- bit) ASCII format P A R I T Y The text characters are transmitted in line 21 of odd-numbered fields by digitally encoded symbols, and in a us segment of the line at a rate of 960bits/sec (120 cps). Closed captioning is one example of the use of the vertical blanking interval of an analog television system for the transmission of digital data. 20/40

Aspect ratio conversion 16:9 4:3 display modes letterbox, pan&scan, squeeze letterbox pan&scan squeeze 4:3 16:9 display modes crop, wide, zoom, spectacle, text Crop Wide

11 Aspect ratio conversion 16:9 4:3 display modes letterbox, pan&scan, squeeze letterbox pan&scan squeeze 4:3 16:9 display modes crop, wide, zoom, spectacle, text Crop Wide Zoom 21/40 Data broadcasting & EPG ASIC Video decoding Arbitrary video scaling OSD bitmap generation, scaling & display CPU Data broadcasting packet parsing HTML, XML, Java 22/40

12 Typical Test patterns Normal Image Full White Full Red Full Green Normal Image Full Blue Full Black EIA Color Bars SMPTE Bars Luminance Color Bars Cross Cross Hatch White Window 23/40 Electronic Display Devices 각종전자기기로부터다양한정보를시각을통해인간에전달하는전자장치 -Emissive display( 발광형 ) : 광정보신호가발광에의해표시 -Non-emissive display( 수광형 ) : 반사, 산란, 간섭현상등에의한주변광의제어즉, 광변조로표시 발광형 CRT(Cathode ray tube : 브라운관디스플레이 ) FED(Field emission display : 전계방출디스플레이 ) ELD(Electro luminescent display : 전계발광디스플레이 ) PDP(Plasma display panel : 플라즈마디스플레이 ) VFD(Vacuum florescent display : 형광표시판디스플레이 ) LED(Light emitting diode : 발광다이오드디스플레이 ) 수광형 LCD(Liquid crystal display : 액정디스플레이 ) DMD(Digital Micromirror Device) LCoS(Liquid crystal on silicon) 24/40

13 CRT : Cathode Ray Tube - 열전자방출현상을이용 - 열전자방출이란금속등을고온으로가열하면그물질을형성하고있는원자속의전자가유리하여공간으로방사되는현상을말한다. TV에서영상을비추어내는수상관 (CRT) 은 1897년독일의물리학자브라운에의해서발명 브라운관이라고도함 CRT는휘도, 시야각, 제조단가, 콘트라스트등이우수하여전세계적으로가장많이사용 현재도전세계디스플레이시장을석권 25/40 CRT 의 Display 원리 Monitor 용 CRT 화소구조 26/40 TV 용 CRT 화소구조

14 Projection TV 의동작원리 27/40 Warping Examples Original Image Pincushion Keystone 28/40 Tilt

15 LCD : Liquid Crystal Display 액정 (Liquid Crystal) 은액체의유동성과고체의결정과같은규칙적인분자배열을동시에가짐 광학적이방성을가지면서전압이가해지면전계의방향을따라액정의분자배열이바뀜 이러한성질을이용하여도형, 문자또는그림을표시 29/40 Structure of Color TFT(Thin film transistor)-lcd Panel 30/40

Lamp 100 W UHP 31/40 PDP : Plasma Panel Display -PDP 발광의원리 1) 형광등의원리를이용하여방전 - 유리기판사이에가스주입 2)

16 LCD Projection TV 의동작원리 Blue reflection Blue reflection Blue relay 1.21 P-Si TFT LCD Panel Blue filter Green filter Red filtering Projection lens Red reflection Lamp 100 W UHP 31/40 PDP : Plasma Panel Display -PDP 발광의원리 1) 형광등의원리를이용하여방전 - 유리기판사이에가스주입 2) 방전과정에서생성된진공자외선에의하여 R,G,B 형광체발광 3) 빨강색 (R), 녹색 (G), 파란색 (B) 광조합을시청 - 플라즈마의특성으로인해밝기조절은안되고 on/off 만가능 -On 되는시간을조정하여각화소의밝기를표현 32/40

17 PDP Panel 의구조 33/40 Bit-plane representation of an 8-bit image 34/40

Bit-plane representation of an 8-bit image Bitplane 7(most

Bitplane 4 35/40 Bitplane 1 Bitplane 0(least significant)

represents the gray levels using the pulse width

In case of moving image, it results in the degradation of

18 Bit-plane representation of an 8-bit image Bitplane 7(most significant) Bitplane 6 Bitplane 3 Bitplane 2 Bitplane 5 Bitplane 4 35/40 Bitplane 1 Bitplane 0(least significant) PDP Panel 에서발생하는전형적인 false contour Plasma display panels represents the gray levels using the pulse width modulation(pwm) technique. In case of moving image, it results in the degradation of image quality, which is often called dynamic false contour. Original(lena) 36/40 False contour by PWM

19 False contour reduction by error diffusion False contour After error diffusion 37/40 DMD : Digital Micromirror Device 38/40

20 DMD 의 Display 원리 39/40 DLP Projection TV 의동작원리 40/40

8-VSB (Vestigial Sideband Modulation)., (Carrier Phase Offset, CPO) (Timing Frequency Offset),. VSB, 8-PAM(pulse amplitude modulation,, ) DC 1.25V, [2

8-VSB (Vestigial Sideband Modulation)., (Carrier Phase Offset, CPO) (Timing Frequency Offset),. VSB, 8-PAM(pulse amplitude modulation,, ) DC 1.25V, [2 VSB a), a) An Alternative Carrier Phase Independent Symbol Timing Offset Estimation Methods for VSB Receivers Sung Soo Shin a) and Joon Tae Kim a) VSB. VSB.,,., VSB,. Abstract In this paper, we propose