System and method for controlling luminance during video production and broadcast
Disclosed herein are systems and methods for controlling luminance during video production and broadcast. An exemplary system includes a camera to capture video content in a first imaging range, a histogram calculator to evaluate luminance in each pixel in the captured video content, and to generate a luminance histogram for the captured video content, a user interface generator that generates a user interface displaying the video content overlaid with the luminance histogram and generates a user interface displaying a light intensity curve and adjustable parameters for converting the first range into a second range, a luminance controller to convert luminance of the video content into the second imaging range based on the light intensity curve, and a broadcast controller to encode the video content with the second imaging range into broadcast range for transmitting to one or more endpoint devices.
1. A system for controlling luminance of video content during video production, the system comprising:
at least one camera configured to capture video content in a first imaging range;
a histogram generator configured to measure a respective luminance level for each of a plurality of pixels in at least one frame of the captured video content, and to generate a luminance histogram based on the measured luminance levels of the plurality of pixels in the at least one frame;
a first user interface configured to display the at least one frame of the captured video content and the generated luminance histogram as an overlay on the displayed at least one frame;
a second user interface configured to display a light intensity curve relative to a plurality of parameters that include at least one of a standard dynamic range (SDR) reference range, an SDR peak white, a tonemap Max-Destination, a tonemap high dynamic range (HDR) range, and a hybrid log-gamma (HLG) monitor;
a luminance controller configured to convert the captured video content in the first imaging range to broadcast video content in a second imaging range that is different than the first image range and has a luminance based on output luminance values of the light intensity curve; and
a broadcast controller configured to encode the broadcast video content in the second imaging range for distribution to at least one content consuming device for display thereon,
wherein the second user interface displays the plurality of parameters and is further configured to adjust the light intensity curve in response to a user adjustment of a value of at least one of the plurality of parameters to set the output luminance values for the luminance controller to convert the captured video content in the first imaging range to the broadcast video content in the second imaging range.
2. The system of claim 1 , wherein the first imaging range is an HDR and the second imaging range is an SDR.
3. The system of claim 2 , wherein the second user interface is configured to receive a selection of one or more of the following HDR to SDR conversion methodologies for converting the captured video content in the first imaging range to broadcast video content in the second imaging range: (1) High Mid-tone Detail Enhancement; (2) Highlight Detection; (3) Strong Highlight Enhancement; and (4) Gamut excursion correction.
4. The system of claim 1 , wherein the captured video content is live video content.
5. The system of claim 1 , wherein the plurality of parameters displayed in the second user interface include each of the SDR reference range, the SDR peak white, the tonemap Max-Destination, the tonemap HDR range, and the HLG monitor.
6. The system of claim 1 , wherein the histogram generator is configured to generate the luminance histogram that includes 16 separate luminance ranges with a first range of the ranges beginning at less than 0.5 nits and a last range of the ranges being for pixels in the 8192-10000 nits range.
7. The system of claim 6 , wherein the histogram generator is configured to generate the luminance histogram by precomputing a one dimensional lookup table, wherein a key of the one dimensional lookup table is X bits.
8. A system for controlling luminance of video content during video production, the system comprising:
at least one camera configured to capture video content in a first imaging range;
a histogram calculator configured to evaluate luminance in the captured video content, and generate a luminance histogram for the captured video content;
a user interface generator configured to:
generate a first user interface displaying the captured video content overlaid with the generated luminance histogram, and
generate a second user interface displaying a light intensity curve configured with parameters for converting the captured video content from the first imaging range into a second imaging range, with the parameters including at least one of a standard dynamic range (SDR) reference range, an SDR peak white, a tonemap Max-Destination, a tonemap high dynamic range (HDR) range, and a hybrid log-gamma (HLG) monitor; and
a luminance controller configured to convert the captured video content into the second imaging range based on the parameters of the light intensity curve,
wherein the second user interface displays the parameters and is further configured to adjust the light intensity curve in response to a user adjustment of a value of at least one of the parameters to control the luminance controller to convert the captured video content into the second imaging range.
9. The system of claim 8 , further comprising a broadcast controller configured to encode the converted video content in the second imaging range for transmitting to one or more endpoint devices.
10. The system of claim 8 , wherein the second user interface includes at least one control input configured adjust a position of the light intensity curve relative to the parameters to set output luminance values for the luminance controller to convert the captured video content in the first imaging range to the second imaging range.
11. The system of claim 8 , wherein the first imaging range is an HDR and the second imaging range is an SDR.
12. The system of claim 11 , wherein the second user interface is configured to receive a selection of one or more of the following HDR to SDR conversion methodologies for converting the captured video content in the first imaging range to broadcast video content in the second imaging range: (1) High Mid-tone Detail Enhancement; (2) Highlight Detection; (3) Strong Highlight Enhancement; and (4) Gamut excursion correction.
13. The system of claim 8 , wherein the captured video content is live video content.
14. The system of claim 8 , wherein the parameters displayed in the second user interface include each of the SDR reference range, the SDR peak white, the tonemap Max-Destination, the tonemap HDR range, and the HLG monitor.
15. The system of claim 8 ,
wherein the histogram calculator is configured to generate the luminance histogram that includes 16 separate luminance ranges with a first range of the ranges beginning at less than 0.5 nits and a last range of the ranges being for pixels in the 8192-10000 nits range, and wherein the histogram calculator is configured to generate the luminance histogram by precomputing a one dimensional lookup table, wherein a key of the one dimensional lookup table is X bits.
16. The system of claim 8 , wherein the luminance controller is further configured to dynamically adjust the second imaging range based on the parameters of the light intensity curve.
17. The system of claim 8 , wherein the user interface generator is further configured to generate the first and second user interface based on endpoint device display information.
18. A system for setting luminance of video content, the system comprising:
a histogram generator configured to generate a luminance histogram based on measured luminance values for at least one region in video content in a first imaging range;
a user interface generator configured to generate at least one user interface configured to display the generated luminance histogram and a light intensity curve with associated parameters for converting the video content from the first imaging range to a second imaging range; and
a luminance controller configured to convert the video content to the second imaging range based on settings of the associated parameters of the light intensity curve,
wherein the at least one user interface is further configured to adjust a position of the light intensity curve in response to a user adjustment of a value of at least one of the associated parameters, and
wherein the parameters displayed in the at least one user interface include a standard dynamic range (SDR) reference range, an SDR peak white, a tonemap Max-Destination, a tonemap high dynamic range (HDR) range, and a hybrid log-gamma (HLG) monitor.
19. The system of claim 18 , further comprising a broadcast controller configured to encode the converted video content in the second imaging range for transmitting to one or more endpoint devices.
20. The system of claim 18 , wherein the first imaging range is an HDR and the second imaging range is an SDR.
21. The system of claim 20 , wherein the at least one user interface is further configured to receive a selection of one or more of the following HDR to SDR conversion methodologies for converting the captured video content in the first imaging range to the second imaging range: (1) High Mid-tone Detail Enhancement; (2) Highlight Detection; (3) Strong Highlight Enhancement; and (4) Gamut excursion correction.
22. The system of claim 18 , wherein the captured video content is live video content.
23. The system of claim 18 ,
wherein the histogram generator is configured to generate the luminance histogram that includes 16 separate luminance ranges with a first range of the ranges beginning at less than 0.5 nits and a last range of the ranges being for pixels in the 8192-10000 nits range, and
wherein the histogram calculator is configured to generate the luminance histogram by precomputing a one dimensional lookup table, wherein a key of the one dimensional lookup table is X bits.
24. The system of claim 18 , wherein the luminance controller is further configured to dynamically adjust the second imaging range based on the parameters of the light intensity curve.
25. The system of claim 18 , wherein the user interface generator is further configured to generate the at least one user interface based on endpoint device display information.