VIDEO TERMINOLOGY
VIDEO STANDARDS
1. NTSC - 525 Scanlines/frame rate - 30fps
North & Central America, Phillipines & Taiwan . NTSC J - Japan has a darker black
2. PAL - 625 scanlines 25 fps Europe, Scandinavia parts of Asia, Pacific & South Africa. PAL in Brazil is 30fps and PAL colours
3. SECAM France Russia Middle East and North Africa
PROGRESSIVE VS INTERLACED VIDEO
All computer monitors use a progressive scan - each scan line in sequence. Interlacing is only for CRT monitors. LCD monitors work totally differently - no need to worry about. Interlacing is for broadcast TV. Every other line displayed alternatively.
FRAME RATES
As we transition from analogue video to digitla video. Film is 24 fps, PAL video 25 fps. NTSC 30fps. Actually film and NTSC are slightly different but we don't need to worry about that for now.
IMAGE SIZE
All video is shot at 72 px/inch -
DV NTSC - 720 x 480 (SD is 720 x 486)
DV PAL - 720 x 576 (SD PAL is 720 x 576)
HD comes in both progressive and interlaced. HD480i is usual broadcast TV 480p is 480 progressive. 720i is 720 interlaced 720p is progressive. 720 means 720 vertical lines 1080 is 1080 vertical lines. 1080i is most popular. 720p is 1280 x 720, HD 1080 is 1920x1080px. All HD formats are 16:9 aspect ratio. Traditional TV is 4:3 aspect ratio.
HDV is 1440 x 1080. New format - is it the new HD version of DV? Cameras like the Sony and JVC make minor alterations to this format when shooting
In summary HD 1080i = 1920 x 1080
HD 720p = 1280 x 720
Traditional = 720 x 480 (NTSC) 720 x 576 (PAL)
VIDEO OUTPUTS
Analog
Composite, S-Video, Component in increasing quality. You will notice the difference in quality.
DIGITAL OUTPUT
Firewire and SDI. Firewire uses a 4pin cable carries digital data from deck to computer. SDI -older format - works for both SD and HD - absolute highest quality.
Digital Audio - most times for transmitting digital audio use Embedded SDI. Remember digital - digital, analogue to analogue - DON"T CROSS THEM!
TAPE FORMATS
VHS (Analogue format) is everywhere, but very low quality. DV - 3 Formats DVCPRO-25(Panasonic), DVCAM (Sony), MiniDV - consortium for a more common format. No discernable differenc in image quality. Can lump these formats into one term - DV.
DVCPRO50 is next step up - gives a much better quality than DV
DVCPRO-HD is next highest quality
New format HDV - same tape size same data rate delivers HD quality picture.
Betacam - see in broadcast environments.
DigiBetacam - higher still. Also D1 and D5
VIDEO AS DATA
DATA RATES
CD Audio (16 bit depth) = 176 kb/sec
DV = 3.75 Mb/sec
HDV
720p = 2.4 Mb/sec, 1080i = 3.2 Mb/sec