JVC GR-HD1 Brochure & Specs Download

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H D C y b e r C a m

The Hybrid Complementary-Primary
progressive color filter system developed by
JVC employs a filter matrix overlaying the
CCD’s picture elements including two
complementary colors Yellow and Cyan (Ye
and Cy), one primary color Green (Gr), and
clear. Shifting one pixel at a time across the
CCD and combining these together in pairs
for brightness and blocks of four for color
delivers maximum resolution. This system’s
superior ability to sample both Y Luminance
and RGB Chroma information results in color
performance nearly identical to using three
CCDs, proving that it is possible to deliver
Hi-Def performance with a single CCD.

Aside from the number of Luminance and
RGB Chroma samples, the die-hard 3-CCD
enthusiast may wish to point out a higher
ratio of Chroma pixels to Luma pixels offered
by 3-CCD (1:1 vs 0.75:1). However, this
actually turns out to be a moot point since
4:2:0 DV or MPEG-2 encoding inevitably
reduces Chroma detail in the R–Y and B–Y
color difference components. Both record
just one sample each of color for every block
of 4 Luma samples. So instead of expending
resources on Chroma detail never used in
the recording process, JVC concentrated on
providing 3-CCD level performance with a
single CCD system tailor-made to provide all
the color sample and resolution requirements
of Hi-Def recording in MPEG-2 format.

Another remarkable aspect of this video

camera is that it records 60 minutes of HD

signals on conventional MiniDV cassette.

The benefits are obvious: MiniDV

cassettes, “the defacto standard”,

are widely available and affordable

compared to other formats used in

professional systems, and by using

a common cassette mechanism with

DV, it was possible for the GR-HD1 to

offer regular DV recording as well.

I B B P B B I

GOP=6

time

MPEG-2

In HDTV, high power MPEG
encoding eliminates redundant
information over time.

I : I Frame (Intra Coded Frame)
B : B Frame (Bi-directionally

Predictive Coded Frame)

P : P Frame (Predictive Frame)

Hi-Def MPEG-2 on MiniDV Cassette

This was made possible since the “Hi-Def

MPEG-2 on MiniDV” encoder and

decoder developed by JVC together with

NTT records Hi-Def Component MPEG2-

TS signals in the same track format as DV.

Digital MPEG-2 Hi-Def and SD Recording

While the picture is encoded one frame at a
time for DV, the time axis is encoded as well
for MPEG-2, conforming to the HD Digital
VCR Conference’s Part 7 (DVB) and Part 8
(ATV) standards. The GR-HD1 uses a GOP
(Group Of Pictures) of 6 for HD and 12 for SD,
with a frame order of IBBPBB. The “I frame” is

Subcode

Video

Audio

Tape low edge (Reference edge)

High-Speed Search Playback Possible

The “I frame” can be played back without

using any other frame and is recorded in

the appropriate variable-speed playback

area on the tape, allowing high-speed

search during playback.

All “TV line” standard measurements are relative to the diameter of a circle the same size as the
picture height. HDTV 16:9 Horizontal TV lines figures appear to be 75% of what the equivalent
4:3 Horizontal TV Lines would be if the measurement was relative to the whole picture width,
since the image is wider.

(For example, for the GR-HD1 HD mode would be around 1244 TV

lines per picture width, while the count would be about 933 TV lines per picture width for a 4:3
camera if both had 700 TV lines counting by standard horizontal resolution).

DV has a practical

recorded horizontal limit of 540 4:3 TV lines, 1280x720p HD has a practical recorded limit of 720
16:9 TV lines using the standard measurement method.

a complete frame without reference to any
past or future frames; the “P frame” is
encoded relative to the past reference frame;
and the “B frame” is encoded relative to the
past reference frame, future reference frame,
or both.

C (Chroma) information is generated by
combining blocks of four picture elements:

R = (W+Ye) – (G+Cy)
G = (G+Cy+Ye) – W
B = (W+Cy) – (G+Ye)

Y (Luminance) information is obtained from
pairs of picture elements:

odd

= (W+G) = (R+2G+B)

even

= (Cy+Ye) = ((G+B)+(R+G)) =

(R+2G+B)

performance renders 3-CCD unnecessary

*The difference between HDTV TV lines and regular TV lines.

1280x659 CCD(s)

CCD Elements