Digital Video

* Characterization of a Digital Video
- frame rate (frames/sec)
- line number (lines/frame)
- sample number per line
- image aspect ratio
- pixel aspect ratio
It is related to IAR and equal to IAR * active lines per frame / active sample num per line. NTSC is 8/9 while PAL is 16/15. For all HDTV formats, it is 1. PAR must be matched in display device.
- chrominance subsampling format
4:4:4, 4:2:2 (honrizontal subsampling only), 4:1:1 (honrizontal subsampling only) and 4:2:0 (chrominance phase might be different)
- bit number per pixel
4:4:4 => 24 bits/pixel
4:2:2 => 16 bits/pixel = (4*8+4*8)/4
4:1:1 and 4:2:0 => 12 bits/pixel

* Digital Video Format
- ITU-T BT601 for SDTV
Uniform sampling frequency for NTSC and PAL: 13.5MHz
Pixel number per line: 858/NTSC and 864/PAL with active pixel of 720/line
Active line numbers: 480 of 525/NTSC and 576 of 625/PAL
Raster scanning: 50I/60I
Color coordinate: YCbCr; 4:4:4, 4:2:2(by default) and 4:2:0
- ITU-T BT709 for HDTV
1920X1080, 24P/30P/60I; 4:2:2; 16:9; 74.25MHz sampling rate and different color coordinates with BT601
- SMPTE 296M
1280X720; 24P/30P/60P; 4:2:0; 16:9
- SMPTE 295M
1920X1080; 24P/30P/60I; 4:2:0; 16:9
- SIF (for VCD/CVD/SVCD)
352X240/288; 30P/25P; 4:2:0; 4:3
- 4CIF
704X480/576; 50I/60I; 4:2:0; 4:3
- CIF
352X240/288; 30P; 4:2:0; 4:3
- QCIF
176X144; 30P; 4:2:0; 4:3
- Sub QCIF
128X96; <30P; 4:2:0; 4:3

* Bit Rate for Some Applications
- HDTV: SMPTE 296/295M, MPEG-2 20~45Mbps
- Video Studio: BT601, MPEG-2 15~50Mbps
- SDTV, DVD: BT601, MPEG-2 4~8Mbps
- VCD, WWW: SIF, MPEG-1 1.5Mbps
- Video conference over ISDN/Internet: CIF, H.26x, 128~384Kbps
- Video telephony over wired/wireless modem: QCIF, H.263, 20~64Kbps
- DVCPRO 50: BT601(4:2:2), MPEG-2, 50Mbps
DVCPRO 25: BT601(4:1:1), MPEG-2, 25Mbps