视频入门－DTV_SystemTechnicalDocumentation

nullATO DTV System Technical DocumentationATO DTV System Technical DocumentationATO HW Team July, 2003Topic of Technical DataTopic of Technical DataFundamental functions of DTV System Color space Analog Input Signal Digital data format Input Input Capture Control Frame Rate Conversion Image/Video enhancement Scalar De-interlace OSD PIP POP Output Display control Color SpaceColor SpaceColor space for Color Difference Video SignalColor space for Color Difference Video SignalColor difference analog Video are YUV and YPbPr The common formula show as below:Signal and Color SpaceSignal and Color SpaceAnalog Signal TV (CVBS), Composite signal (YUV color space) AV, Composite (YUV color space) S-video, Y/C signal (YUV color space) Component, Y/R-Y/B-Y (YUV color Digital 480i– SDTV (YUV) 480p, 720p, 1080i, 1080p---HDTV (Y709CbCr(YPbPr) color space)YUV Color Space YUV Color Space 1.YUV color space is used NTSC, PAL, SECAM composite color video system. 2.Y: Luma information, UV: Color information.YPbPr Color Space (for HDTV)YPbPr Color Space (for HDTV)Input Signal TypeInput Signal TypeRGB DVI CVBS YC Component SDTV HDTV Video Signal Evolution Video Signal Evolution RGB RGB Input Signal level: 1.4Vp-p/2.0Vp-p Signal level Before ADC: 0.7Vp-p/1.0Vp-p Impedance is 75 Ohm Terminator Resister is 75 Ohm Sync level is 300mV Sync type: Composite Sync Separate SyncDVIDVIDigital Data Signal type: Differential signal Signal level: Low noise signal Long distance transmission Differential impedance: 50 Ohm Single ending impedance: 100 OhmCVBS - NTSCCVBS - NTSCResolution: 525 lins, 60 fields per second Bandwidth Y bandwidth:0 ~ 4.2 MHz U or V bandwidth: 1.3MHz Color carrier freq (Fsc): depend on different NTSC Audio carrier freq: 4.5MHz Channel Bandwidth : 6 MHz Video decoder sampling clock > 6MHz * 2 (using 13.5MHz) Color space, YUV NTSC = Y+C = Y +( Usinωt + Vcosωt) + Sync, ω = 2πFsc Fh, Fv and Fsc CVBS- NTSC BandwidthCVBS- NTSC BandwidthCVBS- NTSC BandwidthCVBS- NTSC BandwidthCVBS - NTSCCVBS - NTSCCVBS-NTSC WaveformCVBS-NTSC WaveformCVBS-NTSC Color BarsCVBS-NTSC Color BarsAnalog Video-CVBS waveformAnalog Video-CVBS waveformCVBS- NTSC VariationsCVBS- NTSC VariationsCVBS-PAL SignalCVBS-PAL SignalResolution: 625 lins, 50 fields per second Bandwidth Y bandwidth: depend on different PAL U or V bandwidth: 1.3MHz Color carrier freq (Fsc): depend on different PAL Audio carrier freq: depend on different PAL Channel Bandwidth : depend on different PAL Color space, YUV NTSC = Y+C = Y +( Usinωt + Vcosωt) + Sync, ω = 2πFsc Fsc CVBS- PAL WaveformCVBS- PAL WaveformCVBS – PAL Color BarCVBS – PAL Color BarCVBS- PAL Color BarCVBS- PAL Color BarCVBS- PAL AV IF FreqCVBS- PAL AV IF FreqCVBS – PAL VariationsCVBS – PAL VariationsYC Signal-NTSC/PALYC Signal-NTSC/PALWhy need Y/C signal ? Separate Y and C signal to reduce chroma information on luma And luma information on chroma. S-Video Y/C WaveformS-Video Y/C WaveformS-Video ConnectorS-Video ConnectorSignal for SDTVSignal for SDTVResolution: 480i(720 x 480) Sync Level: Two-level Color space: YUVSDTV- Y WaveformSDTV- Y WaveformSDTV- Color WaveformSDTV- Color WaveformYCbCr- WaveformYCbCr- WaveformYPbPr Signal for HDTVYPbPr Signal for HDTVSignal process different between DTV and NTSC NTSC, Composite -> YC separate -> R601 or R656 (4:2:2) DTV, YPbPr -> 8:8:8 HDTV signal type: Analog RGB Analog YPbPr Digital 4:4:4, 4:2:2 DVI 8:8:8 ( in the future) data format Resolution: 1080p, 1080i(1920 x 1080), 720p (1280 x 720), 480p Sync Level: Tri-level Color space: ITU-R BT.709 HDTV- Y WaveformHDTV- Y WaveformHDTV – Color WaveformHDTV – Color WaveformDigital Data FormatDigital Data FormatRGB(Come from D-sub or DVI connector) Format 8:8:8, 24 bits(one clk one pixel) or 48 bits ( one clk two pixels) Data range: 0 ~ 255 2 pixel = 6 bytes (48 bits) Video (come from Composite, S-video and YPbPr for DTV) 4:4:4 (24 or 48 bit) 2 pixel = YCbCr + YCbCr= 6 bytes (48 bits) ITU-R601 4:2:2 (16 bits), sampling rate=13.5MHz 16 bits data + video clock + H Sync + V Sync 2 pixel = (Y0 U0) + (Y1 V0)=16 bits + 16 bits = 32 bits ITU-R656 4:2:2(8 bit), Sampling rate = 27 MHz 8 bits data + embedded Sync + video clock 2 pixel = Y0 + U0 + Y1 +V0 = 4 bytes = 32 bitsVideo Digital Data Format – 4:4:4 vs 4:2:2 Video Digital Data Format – 4:4:4 vs 4:2:2 Video Digital Data format- 4:2:2Video Digital Data format- 4:2:2 BT656 Format-1BT656 Format-1Y data normal range: 16 ~ 235 CbCr data normal range: 16 ~ 240 (128+/-112). 3. During blanking interval, Y should have a value of 10H CrCb should have a value of 80H.BT656 Format-2BT656 Format-2BT656 Format-3BT656 Format-3ASI510 FunctionASI510 FunctionInput Source muxing. Data format Conversion Input Signal Capture Memory Arrangement Frame Rate Conversion De-Interlace Scalar Image/Video Enhancement Color Space Conversion Display Control ( Signal, PIP, POP, PAP, Digest) OSD ICC Panel Timing Control nullnullADI BLOCKADI BLOCK Input Source Muxing Input Source MuxingInput MUXing select any two of three port input to Channel X and Y Channel. (Three input port are digital port, Video Port #1 and Video Port #2. It include data and control sync. Digital Port (RGB, HDTV, DVI)Digital Port (RGB, HDTV, DVI)1. It is a 8:8:8 data format 2. It could be 24(single pixel) or 48 bits (Dual Pixel) 3. If input timing is 1280x1024 (SXGA) 60 Hz (110Mhz) 24 bits input, pixel clock = 110MHz 48 bits input, pixel clock = 55 MHz 4. Dual pixel problem: Miss alignment (not miss first pixel) Video Port A and BVideo Port A and BR656 8 bits input for each video A and B. R601 16 bits input for combination of video A and B. Input Capture ControlInput Capture Control1. Analog RGB and HDTV Input Find the first pixel( Data Valid), and detect the Sync timing and find H and V total. FW using these information to capture input picture. DVI, R656 and R601 input These format already include sync information, FW just using these sync information to capture the input picture. Input Capture Control-Input RegionInput Capture Control-Input RegionInput Capture Control-Input Color FillInput Capture Control-Input Color FillInput Capture Control- Video Timing Relationship Input Capture Control- Video Timing Relationship Th = Tp * Htotal Tv = Th * Vtotal Notice Th: The period of Horizontal sync Tv: The period of Vertical sync Tp: The period of pixel clock.PLLPLLData Formatter Data Formatter Define Color Space. Define Data format Define frame buffer Addressing Define Video SizeInput Data Format ConversionInput Data Format ConversionRGB (Digital Port) 8:8:8 (24 bits or 48 bits) 2 pixel = 6 bytes (48 bits) DVI (Digital Port) - 8:8:8 (24 bits or 48 bits) - 2 pixel = 6 bytes (48 bits) HDTV (Digital Port) 4:4:4 (24 or 48 bit) 2 pixel = 6 bytes (48 bits) Video ( Video Port A and B) ITU-R601 4:2:2 (16 bits), sampling rate=13.5MHz 2 pixel = (Y0 U0) + (Y1 V0)=16 bits + 16 bits = 32 bits ITU-R656 4:2:2(8 bit), Sampling rate = 27 MHz 2 pixel = Y0 + U0 + Y1 +V0 = 4 bytes = 32 bits Input Data Format ConversionInput Data Format ConversionBecause the max number of bit is 48 bits for 2 pixel, so must have same number of bit for ASI510. So we chose 48 bits for 2 pixel as the ASI510 internal data format. Data formatter Engineer convert data stream from 48 bits to 64 bits to fit 64bits SDRAM data bus requirement. Memory arrangementMemory arrangementWhat is H offset and Memory size for Input Picture ?What is H offset and Memory size for Input Picture ?If output size grater than input size than resolution will be output size otherwise resolution will be input size. Frame Rate Conversion Frame Rate ConversionMost of panel frame rate is around 60 Hz, but input signal not always keep 60Hz, so must change the input signal frame rate to 60Hz. Single frame buffer Problem: Tearing Double buffer It could solve TEARING problem If buffer control is not good, it might cause JUDDER and DROPPING problems. Frame lock mode (no frame buffer) It does have tearing. Judder and dropping problem, but input signal will be limited at same frame rate as panel frame rate. Signal Frame BufferSignal Frame BufferBecause output frame is faster than input frame, you see old frame data one display. -> Tearing problemDouble Frame BufferDouble Frame BufferIf read action start until write buffer is full and convert low frame rate to high frame rate, there is one frame will be repeat. The picture will be move -> stop -> move …, that is “ Judder” problem. If read action start until write buffer is full and convert high frame rate to low frame rate, there is one frame will be skipped. The picture will be move -> jump-> move …, that is “ Dropping” problem. De-Interlace - MethodDe-Interlace - Method1. Line double *2. Line Interpolation 3. Field interpolation 4. Line + field interpolation *5. Combine odd and even field *6. Film mode de-interlace (3:2, 2:2 pull down) Item 2. Line InterpolationItem 2. Line InterpolationLine2 = XOR (line1,Line 3)Item 5. Combine Odd and Even fieldItem 5. Combine Odd and Even field246Save even field and wait for odd field, then combine two field become one frame.3:2 Pull Down3:2 Pull DownScalar EngineScalar EngineScaling: Scale whole picture. Zooming: Scale portion of picture.Horizontal Non-liner Scalar (Panoramic)Horizontal Non-liner Scalar (Panoramic)Horizontal Non-liner Scalar (Panoramic)Horizontal Non-liner Scalar (Panoramic)The panoramic engine divides the input picture into 3 regions Center region, : from L to R, scaling factor: hfactor End region: from start pixel to L0 and from R0 to end pixel, scaling factor: hfactor0. Middle region: from L0 to L and R to R0, scaling factor: between hfactor and hfactor0 The scaling is symmetric at the center of picture. L - L0 = R – R0 L and R are equidistance from the center. There are two type panoramic: Shrinking ( scalar down) and expanding (scalar up) Application: 4:3 scaling up to 16:9 16:9 scaling down to 4:3Image/Video EnhancementImage/Video EnhancementSharpness LTI ( Luma Transition Improvement) CTI (Chroma Transition Improvement) B/W Intensity Extension Input Output Noise Reducing Filter Gamma Sharpness-OutputSharpness-OutputThe LTI and CTI make the Y or color transition more sharp but might cause the overshoot or undershoot problemSharpness Filtering Control RegisterSharpness Filtering Control RegisterApplication: For luminance and chrominance separately of YPbPr/YCbCr format. For luminance only of RGB input. For LTI and CTI There are four type of filter, Horizontal Y filter Horizontal C filter Vertical Y filter Vertical C filter asi_x_sharpness_1_limit 0x029A[7:6] R/W This register control the horizontal luminance filter overshooting limitation. 0: no overshooting limitation 3: max overshooting limitation. (reduce the overshooting much)Input B/W Intensity Extension Input B/W Intensity Extension Input B/W Intensity Extension- WhiteInput B/W Intensity Extension- WhiteB/W Intensity Extension-BlackB/W Intensity Extension-BlackGamma-OutputGamma-OutputASI510 output is after gamma correction Gamma correction is for panel white balance compensation. Gamma = 64 /[(16+I)*2^N)] N = asi_x_gamma_%[7:6], % is blue, green or red I = asi_x_gamma_%[5:2], % is blue, green or redBrightness and Contrast Adjustment -OutputBrightness and Contrast Adjustment -OutputDigital contrast (Gain): Change slope Digital Brightness: Add or sub same offset for RGBHue and Saturation Adjustment-OutputHue and Saturation Adjustment-OutputMain and Sub window has own control registers Hue and Saturation adjustment only for YCbCr and YPbPr. Disable this function in RGB color spce. Hue: (the color tint of an image) asi_x_hue_cosine and asi_x_hue_sine (these two register value is in two’s compliment value. Saturation: ( the intensity of the color) Asi_x_saturation Hue and Saturation Adjustment Control RegisterHue and Saturation Adjustment Control Register(Y = 128* SIN Θ, X = 128* COS Θ) asi_x_hue_cosine = two’s compliment (128 * COS Θ) asi_x_hue_sine = two’s compliment (128 * SIN Θ)Display ControlDisplay ControlnullDisplay Features (PIP)Picture in PictureVideo 1Video 2Video 2Video 1Supports 4:3 and 16:9 aspect ratio PIP Window can be scaled to 4:3 or 16:9 aspect ratio video Interchangeable video source between background or PIP window Programmable PIP Window size and location Keystone supportPIP WindowPIP WindowBackground WindowBackground WindowPIP/POP Control RegisterPIP/POP Control Registerasi_y_border_width 0x017B[7:4] RW This register define the PIP border width in pixel asi_y_pop_border_hend_msb 0x02AF[6:4] RW asi_y_pop_border_hend_lsb 0x02AD[7:0] RW asi_y_pop_border_hstart_msb 0x0181[6:4] RW asi_y_pop_border_hstart_lsb 0x017F[7:0] RW asi_y_pop_border_vend_msb 0x02AF[2:0] RW asi_y_pop_border_vend_lsb 0x02AE[7:0] RW asi_y_pop_border_vstart_msb 0x0181[2:0] RW asi_y_pop_border_vstart_lsb 0x0180[7:0] RW Display Features (POP Mode 1)Display Features (POP Mode 1)Video 1Video 2Video 1Video 2Picture Over Picture16:9 video source with both displaying simultaneously Video source interchangeable between display windows Panoramic viewing can be independently enabled for either display window Keystone supported with Panoramic scaling enabledDisplay Features (POP Mode 2)Display Features (POP Mode 2)Video 1Video 2Picture Over PictureVideo 1Video 2Video 2Video 1Best for 4:3 aspect ratio Equal size by size display Enlarged primary video of interest for viewingDisplay Features (PIG)Display Features (PIG)PC GraphicsVideo 1PC GraphicsVideo 2Picture in Graphics (TV / Monitor ONLY)Supports PC graphics input with triple ADC Supports PC digital graphics interface Either video source can be overlay on top of graphics Video window size programmable (same as PIP mode) Can be used in internet ready appliance