ColorBox In-Line Color and HDR/SDR Transform v1.0 33 www.aja.com
ORION-CONVERT Parameters
Pre-compression/Pre-expansion
Knee -
This controls the breakpoint where compression or expansion begins on
the selected “input” signal for the conversion. Example: In an up-conversion
(SDR to HDR), the breakpoint will be applied at this level to boost the SDR
into the HDR domain, but may be moved by the subsequent Post-conversion
process.
Amount -
This controls the amount of compression in down-conversion and
expansion in up-conversion. When compressing, a value of zero applies no
compression (at which point the value of Knee is irrelevant) and a value of 1
will compress completely, flattening everything above the value of Knee to
that value.
Conversion
Direction
Here you choose the direction of the colorimetric conversion needed. Select
from:
• HLG to SDR
• SDR to HLG
• HLG Compress
• PQ to HLG
• SDR to PQ
• PQ Compress
• HLG to PQ
• PQ to HLG
NOTE: After finding the settings desired for the conversion (pre-compression and post-
compression), if the direction of the conversion is then reversed, the values of
pre and post compression are swapped to generate an absolute mathematical
inverse. This way, a visually lossless round trip is possible.
Mode
Select from:
Display light -
Display-Light mapping is used when the goal is to preserve the
colors and relative tones seen on an SDR BT.709 or BT.2020 display, when
the content is shown on a BT.2100 HDR display (or on an SDR depending on
the direction of the conversion). An example of which is the inclusion of SDR
graded content within an HDR program. This type of conversion, for example,
would be used for graphics insertion. These elements are mostly designed
(creative intent) in an sRGB environment, so to preserve this creative intent,
we want to represent these elements exactly as they were seen at the time of
their creation.
Scene light -
Scene-Light mapping is used where the source is a direct SDR
camera output or an HDR camera output, and the goal is to match the colors
and tones of that camera to another camera source after conversion. We
would use these conversions when the appearance of the content, as seen by
a camera, is the intended process. For example, when using the SDR output
of a Camera (as camera splits/isos, etc…) that can simultaneously produce
SDR and HDR, we want the HDR program (after conversion to SDR) to match