вот это было прочитано - и возник вопрос - в чем качественное отличие ??? что будет при попытке подключит С двд к P входу телека?
из прочитанного можно сделать вывод что СbCr - цифровой... но это же надеюсь не так???? или это действительно разложенный на три првода ЦИФРОВОЙ CCIR-601 aka SDI?
Зачем входы Y-Pb-Pr Y-Cb-Cr делают цветными red green blue ?
я пологал/пологаю что RGB телевизионное - 3 проводника + синхронизация мутно подмешенная в кажый (или в определенный) - проблема в том что я не нашел ни одного такого девайса....
Или я не прав и RGB про который говорится в бытовой техники это нормальный VGA (синхронизация идет отдельно или композитно или как в старых случаях c SGI подмешивается в зеленый) ???
========================
YPbPr
If three components are to be conveyed in three separate channels with
identical unity excursions, then the Pb and Pr colour difference
components are used:
Pb = (0.5/0.886) * (Bgamma - Y)
Pr = (0.5/0.701) * (Rgamma - Y)
These scale factors limit the excursion of EACH colour difference
component to -0.5 .. +0.5 with respect to unity Y excursion: 0.886 is just
unity less the luma coefficient of blue. In the analog domain Y is usually
0 mV (black) to 700 mV (white), and Pb and Pr are usually +- 350 mV.
YPbPr is part of the CCIR Rec. 709 HDTV standard, although different luma
coefficients are used, and it is denoted E'Pb and E'Pr with subscript
arrangement too complicated to be written here.
YPbPr is employed by component analog video equipment such as M-II and
BetaCam; Pb and Pr bandwidth is half that of luma.
YCbCr
The international standard CCIR Recommendation 601-1 specifies eight-bit
digital coding for component video, with black at luma code 16 and white
at luma code 235, and chroma in eight-bit two's complement form centred on
128 with a peak at code 224. This coding has a slightly smaller excursion
for luma than for chroma: luma has 219 "risers" compared to 224 for Cb and
Cr. The notation CbCr distinguishes this set from PbPr where the luma and
chroma excursions are identical.
For Rec. 601-1 coding in eight bits per component,
Y_8b = 16 + 219 * Y
Cb_8b = 128 + 112 * (0.5/0.886) * (Bgamma - Y)
Cr_8b = 128 + 112 * (0.5/0.701) * (Rgamma - Y)
Some computer applications place black at luma code 0 and white at luma
code 255. In this case, the scaling and offsets above can be changed
accordingly, although broadcast-quality video requires the accommodation
for headroom and footroom provided in the CCIR 601-1 equations.
CCIR Rec. 601-1 calls for two-to-one horizontal subsampling of Cb and Cr,
to achieve 2/3 the data rate of RGB with virtually no perceptible
penalty. This is denoted 4:2:2. A few digital video systems have utilized
horizontal subsampling by a factor of four, denoted 4:1:1. JPEG and MPEG
normally subsample Cb and Cr two-to-one horizontally and also two-to-one
vertically, to get 1/2 the data rate of RGB. No standard nomenclature has
been adopted to describe vertical subsampling. To get good results using
subsampling you should not just drop and replicate pixels, but implement
proper decimation and interpolation filters.
YCbCr coding is employed by D-1 component digital video equipment.
из прочитанного можно сделать вывод что СbCr - цифровой... но это же надеюсь не так???? или это действительно разложенный на три првода ЦИФРОВОЙ CCIR-601 aka SDI?
Зачем входы Y-Pb-Pr Y-Cb-Cr делают цветными red green blue ?
я пологал/пологаю что RGB телевизионное - 3 проводника + синхронизация мутно подмешенная в кажый (или в определенный) - проблема в том что я не нашел ни одного такого девайса....
Или я не прав и RGB про который говорится в бытовой техники это нормальный VGA (синхронизация идет отдельно или композитно или как в старых случаях c SGI подмешивается в зеленый) ???
========================
YPbPr
If three components are to be conveyed in three separate channels with
identical unity excursions, then the Pb and Pr colour difference
components are used:
Pb = (0.5/0.886) * (Bgamma - Y)
Pr = (0.5/0.701) * (Rgamma - Y)
These scale factors limit the excursion of EACH colour difference
component to -0.5 .. +0.5 with respect to unity Y excursion: 0.886 is just
unity less the luma coefficient of blue. In the analog domain Y is usually
0 mV (black) to 700 mV (white), and Pb and Pr are usually +- 350 mV.
YPbPr is part of the CCIR Rec. 709 HDTV standard, although different luma
coefficients are used, and it is denoted E'Pb and E'Pr with subscript
arrangement too complicated to be written here.
YPbPr is employed by component analog video equipment such as M-II and
BetaCam; Pb and Pr bandwidth is half that of luma.
YCbCr
The international standard CCIR Recommendation 601-1 specifies eight-bit
digital coding for component video, with black at luma code 16 and white
at luma code 235, and chroma in eight-bit two's complement form centred on
128 with a peak at code 224. This coding has a slightly smaller excursion
for luma than for chroma: luma has 219 "risers" compared to 224 for Cb and
Cr. The notation CbCr distinguishes this set from PbPr where the luma and
chroma excursions are identical.
For Rec. 601-1 coding in eight bits per component,
Y_8b = 16 + 219 * Y
Cb_8b = 128 + 112 * (0.5/0.886) * (Bgamma - Y)
Cr_8b = 128 + 112 * (0.5/0.701) * (Rgamma - Y)
Some computer applications place black at luma code 0 and white at luma
code 255. In this case, the scaling and offsets above can be changed
accordingly, although broadcast-quality video requires the accommodation
for headroom and footroom provided in the CCIR 601-1 equations.
CCIR Rec. 601-1 calls for two-to-one horizontal subsampling of Cb and Cr,
to achieve 2/3 the data rate of RGB with virtually no perceptible
penalty. This is denoted 4:2:2. A few digital video systems have utilized
horizontal subsampling by a factor of four, denoted 4:1:1. JPEG and MPEG
normally subsample Cb and Cr two-to-one horizontally and also two-to-one
vertically, to get 1/2 the data rate of RGB. No standard nomenclature has
been adopted to describe vertical subsampling. To get good results using
subsampling you should not just drop and replicate pixels, but implement
proper decimation and interpolation filters.
YCbCr coding is employed by D-1 component digital video equipment.
))