Charge Coupled Device (CCD) < 10  m x 10  m Silicon cells emit electrons when light falls on it

time charge Charge Coupled Device (CCD) luminance cell < 10  m x 10  m

Y=0.299R G B Filters over cells More green than red, blue (For color tv and…?)

CCD Cameras Good links: – Some device specs: –

Color TV Multiple standards - US, 2 in Europe, HDTV standards, Digital HDTV, Japanese analog.Digital HDTV, US: 525 lines (US HDTV is digital, and data stream defines resolution. Typically MPEG encoded to provide 1088 lines of which 1080 are displayed)

NTSC Analog Color TV 525 lines/frame Interlaced to reduce bandwidth –small interframe changes help Primary chromaticities:

NTSC Analog Color TV These yield RGB2XYZ = Y=0.299R G B (same as luminance channel for JPEG!) = Y value of white point. Cr = R-Y, Cb = B-Y with chromaticity: Cr: x=1.070, y=0; Cb: x=0.131 y=0; y(C)=0 => Y(C)=0 => achromatic

NTSC Analog Color TV Signals are gamma corrected under assumption of dim surround viewing conditions (high saturation). Y, Cr, Cb signals (E Y, E r, E b ) are sent per scan line; NTSC, SECAM, PAL do this in differing clever ways E Y typically with twice the bandwidth of E r, E b

NTSC Analog Color TV Y, Cr, Cb signals (E Y, E r, E b ) are sent per scan line; NTSC, SECAM, PAL do this in differing clever ways. – E Y with 4-10 x bandwidth of E r, E b –“Blue saving”

Digital HDTV FCC seeks proposals for advanced tv –Broadcast industry wants analog, 2x lines of NTSC for compatibility –Computer industry wanta digital 1993 (February) DHDTV demonstrated –in four incompatible systems 1993 (May) Grand Alliance formed

Digital HDTV 1996 (Dec 26) FCC accepts Grand Alliance Proposal of the Advanced Televisions Systems Committee ATSCAdvanced Televisions Systems Committee 1999 first DHDTV broadcasts

Digital HDTV lineshpixaspect framesframe rate ratio /9 progressive 24, 30 or /9 interlaced /9 progressive 24, 30 MPEG video compression Dolby AC-3 audio compression