Dietro l HDMI. Adriano D Alessio. Copyright 2015 by InfoComm International

Transcription

1 WEBINARS Dietro l HDMI Adriano D Alessio Copyright 2015 by InfoComm International

2 Interfacce Digitali 2 / 222

3 Rappresentazione del Video Digitale Frame (da 24 a 120frame/sec) Pixel 640x x2400 Subpixel rosso, verde eblu 3 / 222

4 Risoluzioni Standard Single link resolutions Dual link resolutions 640x480 (VGA) 720x x x1024 (SXGA) 1920x x1200 (UXGA) 1920x x1600 (WQXGA) 3840x2160 (Quad HD) 3840x x x / 222

5 DVI full frame VSYNC Blanking interval Active video area Active lines Blanking interval: Control data VSYNC HSYNC Active video area: RGB pixels Active columns Typical HSYNC values: Typical VSYNC values: [khz] [Hz] VSync = Frames Per Second HSYNC 5 / 222

6 Example: VSYNC 1125 lines Active video area 1920 pixels 41 lines 2200 pixels 1080 lines Verticalsync: 60 [Hz] Horizontalsync: 67.7 [khz] Pixel clock: [MHz] Data rate: [Gb/s/color] 279 pixels 1 pixel Aggregated data rate: [Gb/s] 4 lines HSYNC 6 / 222

7 Digital video representation = Full color 8bit / color 8bit = 2 8 = 256level f PCLK = x FULL y FULL f VSYNC X FULL : total number of columns y FULL : total number of lines f VSYNC : framerate ( frames/sec Hz) Pixel clock Example: 60Hz X FULL : 2200pixels y FULL : 1125lines f VSYNC : 60Hz f PCLK: 148.5MHz = 0 10 Black (no color) 3 components together: 256x256x256 ~ 16.7 million color shades 7 / 222

8 vs pixels 2160 pixels Active video area Active video area 1235 lines 1920 pixels 1200 lines 1250 lines 1600 pixels 1200 lines Pixel clock: 2080 x 1235 x 60 = 154MHz Pixel clock: 2160 x 1250 x 60 = 162MHz 1600x1200@60has smaller active video area, but it has higher pixel clock and data rate! 8 / 222

9 Digital video representation Red, green and blue x8 bit / pixel x10 bit / pixel Binary representation Electrical representation Minimizing transitions The twoextra bitscarry coding information. T.M.D.S. = Transition Minimized Differential Signaling 9 / 222

10 T.M.D.S. Transition minimizing XOR XNOR 7 transitions th bit 4 transitions 5 transitions Don t invert Invert th bit 10bit TMDS = 8bit color + 2 bit encoding information 10 / 222

11 T.M.D.S. Single ended vs. differential signals Voltage Voltage 1V High 1V High GND Time Low GND 0 or 1? Time Low Signal GND Source Display 11 / 222

12 T.M.D.S. Single ended vs. differential signals 1V GND High Low Noise affects both wires the same way. The voltage difference is always the same between the two wires. 1V GND Inverted signal High Low Source Display 12 / 222

13 Digital video transmission source TMDS0 long DVI cable (twisted pairs) sink TMDS1 TMDS2 TMDS clock 500 mv 500mV 5 mv jitter Transition minimized signal Differential signal (TMDS) Received signal + Noise + Skew + Jitter + Attenuation T.M.D.S. = Transition Minimized Differential Signaling Jitter is signal instability in the time domain 13 / 222

14 Issue 1 Attenuation 1 V Full HD Source 100 Depends on: frequency diameter of wires lengthof cable Amplitude(%) 10mV Frequency [MHz] Sink 14 / 222

15 Issue 2 Crosstalk between pairs Source 0 Full HD Crosstalk can be reduced by shielding the individual pairs. GainindB Frequency [MHz] Sink 15 / 222

16 Issue 3 Intra-pair skew Source Intra-pair skew subtraction Sink jitter 16 / 222

17 Eye pattern Millions of samples drawn 000 on top of each other / 222

18 Eye pattern Jitter 18 / 222

19 Eye pattern 19 / 222

20 Issue 4 Inter-pair skew Source Inter-pair skew Sink 20 / 222

21 Issue 4 Inter-pair skew? R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 21 / 222

22 TMDS Reclocking Pixel Accurate Reclocking R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 G0 G1 G2 G3 G4 G5 G6 G7 G8 G9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 TMDS Recklocking Re-aligning max. 1bit Pixel Accurate Recklocking Re-aligning the pixels 22 / 222

23 Transmission errors Long cable DVI repeater No reclocking Long cable DVI repeater No reclocking Errors are aggregated when using multiple non-reclocking DVI repeaters. Noise Random red, green or blue dots Jaggies Flashing horizontal lines Loss of sync Unstable picture Pixel Accurate Reclocking repairs all of these errors. 23 / 222

24 DVI & HDMI connectors DVI-D (single link) DVI-D (dual link) DVI-I (single link) DVI-I (dual link) 3data + 1clock TMDS 6data + 1clock TMDS 3data + 1clock TMDS Analog RGBHV pins 6data + 1clock TMDS Analog RGBHV pins DVI-A (analog) Analog pins only (rarely used) HDMI type A 3data + 1clock TMDS CEC line 14mm x 4.55mm HDMI type B (dual link) 6data + 1clock TMDS CEC line 21.3mm x 4.55mm HDMI type C Mini 3data + 1clock TMDS CEC line HDMI type D Micro 3data + 1clock TMDS CEC line 10.42mm x 2.5mm 5.9mm x 2.3mm 24 / 222

25 DVI & HDMI cables Consumer Electronics Control HDMI only! Shield Power5V and Hotplug Handshake signals There is no seperate wireforaudio! Audio is EMBEDDED HDMI cable (single link) 4 TMDS lane(twisted pair) High speed, unidirectional Reserved 2 wire Display Data Channel bus Ground AWG: American wire gauge Lower is thicker Thicker is better Low speed, bidirectional EDID, HDCP communications Typical values: 24 AWG 22 AWG 25 / 222

26 Maximum achievable cable lengths Resolution f PCLK Cat5e UTP Cat5e FTP CAT6 UTP CAT6 FTP CAT6 SFTP CAT7 SFTP 24 AWG 22 AWG 640x480p Mhz 60 m 60 m 65 m 70 m 70 m 80 m 100 m 120 m 800x600p MHz 60 m 60 m 65 m 65 m 65 m 75 m 84 m 100 m 1024x768p MHz 55 m 55 m 60 m 60 m 60 m 75 m 77 m 92 m 1280x720p MHz 55 m 55 m 60 m 60 m 60 m 70 m 77 m 92 m 1280x1024p MHz 50 m 50 m 55 m 60 m 60 m 65 m 62 m 75 m 1400x1050p MHz 45 m 45 m 45 m 55 m 55 m 60 m 62 m 75 m 1920x1080p Mhz 30 m 35 m 35 m 45 m 45 m 50 m 50 m 60 m 1920x1200p MHz 30 m 35 m 35 m 45 m 45 m 50 m 50 m 60 m 1600x1200p MHz 30 m 35 m 35 m 45 m 45 m 50 m 50 m 60 m Distanza raggiungibile con 40dB di riequalizzazione 26 / 222

27 CATx cables for DVI and HDMI Advantages Thin, flexible, easy to string Connectors can be crimped It is the cheapest solution Already in the building Disadvantages Unreliable connectors Higher attenuation Noise sensitive (cell phones) Different number of twists Decreases crosstalk Increases inter-pair skew 27 / 222

28 HDBaseT Designed to complement HDMI, not to replace it An HDMI signal is required by the HDBaseTchip 5Play TM : Video + Audio + Control + Ethernet + Power The coding scheme is proprietary (uses PAM16) Similar to 10 GBaseT, but not ethernet(doesn t use packets or IP protocol) Less sensitive to problems related to CATx cables (skew, crosstalk, attenuation) 28 / 222

29 Data over HDBaseT Full duplex transmission over four wire pairs HDBaseT Transmitter HDBaseT Receiver HDBaseT TX HDBaseT RX

30 High Definition Multimedia Interface 30 / 222

31 HDMI vs. DVI DVI no embedded audio RGB only, 24 bits per pixel A DVI cable CAN carry an HDMI signal with audio!!! Backwards compatible HDMI 1.0 PCM, Dolby, DTS YCbCr 4:4:4,YCbCr 4:2:2 CEC line HDMI DVD audio support HDMI 1.2 Super Audio CD HDMI 1.3 Dolby TrueHD, DTS-HD Master Audio xvycc, Deep Color HDMI Hz 3D, ARC, ethernet HDMI Hz YCbCr 4:2:0, Rec audio streams, 32 channel audio 31 / 222

32 HDMI full frame VSYNC INFO FRAME AUDIO AUDIO AUDIO AUDIO Active video area Active columns AUDIO Active lines Blanking interval: VSYNC HSYNC HDCP status Data packets -Audiodata - InfoFrames AUDIO Active video area: RGB orycbcr pixels AUDIO AUDIO HSYNC Typical VSYNC values: Typical HSYNC values: [Hz] [khz] Thereis no separatewireforaudio! Audiois EMBEDDED 32 / 222

33 Infoframes over HDMI AVI Infoframe Audio Infoframe Colorspace (RGB, YCbCr 4:4:4 or 4:2:2) Pixel repetition factor Barinfo Aspect ratio Video mode, resolution Applied audio codec Channel count Sampling frequency Sample size Speaker allocation InfoFrames cannot be embedded in DVI signal 33 / 222

34 Infoframes Color space conversion PC monitor (DVI-only) HDTV (HDMI compliant) YCbCr YCbCr HDMI/DVI repeater 34 / 222

35 8-bit YCbCr color space YCbCr 4:4:4 All channels use the same bandwidth(8 bits/pixel) Qualityis equivalenttorgb YCbCr 4:2:2 Cb and Cr channels are undersampled Quality loss in exchange for lower bandwidth Compressed video is mostly stored inycbcr 4:2:2 HDMI usesthesamepixel clockasin 4:4:4mode. 12 bits/component is transmitted Iffewerbitsareused, zerosaresent. DVI cable may carry YCbCr HDMI signal 35 / 222

36 YCbCr sampling methods 4:4:4 4:2:2 4:2:0 4:1:1 Y YCbCr Cr = RGB quality H.264/ MPEG-4 H.262/ MPEG-2 BluRay DVD, JPEG 36 / 222

37 Deep Color modes HDMI bits/color 10 bits/color 12 bits/color HDMI 1.3 Optional 30bpp, 36bpp and 48bpp support 36bpp = 2 36 colors= shade In Deep Color modes TMDS clock frequency is the multiple of pixel clock frequency (1.25x, 1.5x, 2x) Higher bandwidth is needed Example: 1920x1080p60 at 36bpp TMDS clock 223MHz, Pixel clock 148.5MHz 37 / 222

38 Pixel clock vs. TMDS clock 24 bpp: Pixel 1 Pixel 2 B0 B1 B2 B3 B4 B5 B6 B7 B0 B1 B2 B3 B4 B5 B6 B7 36 bpp: Pixel 1 Pixel 2 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 24bpp 30bpp 36bpp 48bpp Pixel clock f f 1.25 f 1.5 f 2

39 HDMI 1.4 HDMI Ethernet Channel Audio Return Channel (ARC) 3D over HDMI 4K 2K ResolutionSupport Micro HDMI Connector Automotive Connection System 39 / 222

40 HDMI 1.4 HEC: HDMI Ethernet Channel ARC: Audio Return Channel TMDS DDC +5V CEC HotPlug(HEC & ARC) Reserved(HEC) 40 / 222

41 HDMI 1.4 Audio Return Channel Video Audio HDMI ( Embedded Audio) HDMI 1.3 scenario 5.1 audio HDMI 1.4with ARC 2.0 audio 41 / 222

42 HDMI 1.4 Ethernet Ethernet Internet HDMI 1.4 HDMI 1.3 No need 42 / 222

43 HDMI 2.0 The newest standard 60Hz YCbCr 4:2:0 Rec channel audio 4 audio streams 2 video streams 21:9 aspect ratio 43 / 222