GRASS VALLEY XIP-3901, Руководство пользователя

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XIP - 3901
User Manual
Table 3 – LUT Conversions and variant table
LUT Conversion Description
SDR to HLG Scene (4-
1a - v1.4)
For use with SDR cameras that approximate the BT.709 OETF with a square root
BT.709 signals are directly mapped into BT.2100 HLG at the BT.2408 signal levels
using a scene-light (scene-referred) conversion. The “look” of the original BT.709
content is changed to match native BT.2100 HLG cameras. 100% SDR signal is
mapped to 75% HLG (HDR Reference White).
SDR to HLG Scene
Strict (4-2a - v1.4)
For use with SDR cameras that implement a strict BT.709 OETF
BT.709 signals are directly mapped into BT.2100 HLG at the BT.2408 signal levels
using a scene-light (scene-referred) conversion. The “look” of the original BT.709
content is changed to match native BT.2100 HLG cameras. 100% SDR signal is
mapped to 75% HLG (HDR Reference White).
NOTE: Unlike BT.2100 HLG, SDR cameras that implement a strict BT.709 OETF tend
to crush detail in the shadows of a scene. That detail will become more visible after
applying this conversion.
SDR to HLG Scene
Upmap (6-1a - v1.4)
For use with SDR cameras that approximate the BT.709 OETF with a square root.
BT.709 signals are inverse tone mapped (up-converted) to BT.2100 HLG using a
scene-light (scene-referred) conversion. The “look” of the original BT.709 content is
changed to match native BT.2100 HLG cameras. Whilst the ITU-R BT.2408 signal
levels are taken into account, a small boost is applied to the SDR highlights to
better match natively produced HDR content. 100% SDR signal is inverse tone
mapped to 79% HLG. 105% SDR signals (EBU R.103 signal levels) are inverse tone-
mapped to 83% HLG.
SDR to HLG Scene
Upmap Strict (6-2a -
v1.4)
For use with SDR cameras that implement a strict BT.709 OETF
BT.709 signals are inverse tone mapped (up-converted) to BT.2100 HLG using a
scene-light (scene-referred) conversion. The “look” of the original BT.709 content is
changed to match native BT.2100 HLG cameras. Whilst the ITU-R BT.2408 signal
levels are taken into account, a small boost is applied to the SDR highlights to
better match natively produced HDR content. 100% SDR signal is inverse tone
mapped to 79% HLG. 105% SDR signals (EBU R.103 signal levels) are inverse tone-
mapped to 83% HLG.
NOTE: Unlike BT.2100 HLG, SDR cameras that implement a strict BT.709 OETF tend
to crush detail in the shadows of a scene. That detail will become more visible after
applying this conversion.
SDR to HLG Display
(3c - v1.4)
Display-referred direct mapping maintaining SDR "look". 100% SDR maps to 75 %
HLG (HDR Reference White - see ITU-R BT.2408 and BT.2390). Recommended for
matching the displayed color of SDR graphics.
SDR to HLG Display
Upmap (5c - v1.4)
BT.709 signals are inverse tone mapped (up-converted) to BT.2100 HLG using a
display-light (display-referred) conversion. This LUT is designed to complement
LUT 8 (BT.2100 HLG to BT.709 tone mapping - display-light) to reduce round-
tripping losses (SDR to HDR to SDR conversion).
Whilst the ITU-R BT.2408 signal levels are taken into account, a modest boost is
applied to the SDR highlights to better match natively produced HDR content. The
LUT, however, attempts to preserve the artistic intent of the original BT.709
content. 100% SDR signal is inverse tone mapped to 83% HLG.