GRASS VALLEY XIP-3901, Руководство пользователя

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XIP - 3901
User Manual
HLG to SDR Display
Harsh (9c - v1.4)
HDR-graded content and live programs with graphics - BT.2100 HLG to BT.709,
downmapping (display-light) using SDR “super-whites”.
BT.2100 HLG signals are down-mapped (tone-mapped) to BT.709 using a display-
light conversion. Colors and the appearance of mid-tones and lowlights are
maintained after conversion. The LUT, therefore, attempts to preserve the artistic
intent of the original HLG content.
“HDR Reference White” (75% HLG) is mapped to 95% BT.709 and HDR highlights
extend into the SDR super-white region; for that reason, only “Full-Range Mode”
Type III LUTs are made available. 94% HLG signal is mapped to the EBU R103
preferred maximum of 105% BT.709. HLG signals above 94% are clipped.
This LUT is recommended for use in scenarios where minimizing SDR>HDR>SDR
“round-trip” losses is of the utmost importance. Minimal round-trip losses are
achieved when used with the display-light up-mapping LUT5. Better overall results
are, however, usually achieved with the LUT8 down-mapper, which does not rely
on the SDR super-white signal ranges being maintained through the program
delivery and distribution chains.
PQ 1000 Nits Full
Range to HLG (1c -
v1.4)
BT.2100 PQ signals are converted to BT.2100 HLG at the 1000 cd/m
2
“bridge”
condition, so that 1000 cd/m
2
PQ maps to 100% HLG. See ITU-R report BT.2390
Section 7.2. PQ signals above 1000 cd/m
2
are mapped into the HLG “super-white”
signal range up to a maximum of 1810 cd/m
2
, corresponding to 109% HLG (10-bit
code value 1019).
PQ 1000 Nits Narrow
Range to HLG (1e -
v1.4)
BT.2100 PQ signals are converted to BT.2100 HLG at the 1000 cd/m
2
“bridge”
condition, so that 1000 cd/m
2
PQ maps to 100% HLG. See ITU-R report BT.2390
Section 7.2.
PQ 4000 Nits Full
Range to HLG (2c -
v1.4)
4000 cd/m
2
BT.2100 PQ signals are converted to BT.2100 HLG by first tone
mapping to the 1000 cd/m
2
“bridge” condition, and then converting to HLG. The
tone mapping is applied on the luminance component to avoid hue distortions.
4000 cd/m
2
PQ maps to 100% HLG. See ITU-R report BT.2390 Section 7.4
PQ 4000 Nits Narrow
Range to HLG (2e -
v1.4)
4000 cd/m
2
BT.2100 PQ signals are converted to BT.2100 HLG by first tone
mapping to the 1000 cd/m
2
“bridge” condition, and then converting to HLG. The
tone mapping is applied on the luminance component to avoid hue distortions.
4000 cd/m
2
PQ maps to 100% HLG. See ITU-R report BT.2390 Section 7.4. PQ
signals above 4000 cd/m
2
are mapped into the HLG “super-white” signal range.
HLG to PQ 1000 Nits
Narrow range (7c -
v1.4)
BT.2100 HLG signals are converted to BT.2100 PQ at the 1000 cd/m
2
“bridge”
condition, so that 100% HLG maps to 1000 cd/m
2
PQ. See ITU-R report BT.2390
Section 7.2. HLG signals above 100% are mapped to PQ signals greater than 1000
cd/m
2
, up to a maximum of 1810 cd/m
2
, corresponding to 109% HLG (10-bit code
value 1019).
SLog3 100% Scene to
HLG (10a - v1.4)
S-Log3 signals produced using the Sony’s “100 %” workflow (for example, 100% IRE
input equals 90% reflectance) are converted to BT.2100 HLG with ITU-R BT.2408
signal levels. Thus a 100% IRE input signal (90% reflectance) maps to 73% HLG.
A scene-light conversion is used, so that the converted S-Log3 signal matches the
“look” of BT.2100 HLG cameras.
LUT Conversion Description