Brief Introduction to SDR & HDR
Development of HDR
The increase in resolution is accompanied by improved image quality and clarity. However, measuring image quality involves additional standards beyond resolution. HDR (High Dynamic Range) video offers a broader range of brightness and a wider color spectrum, resulting in images that appear more realistic and natural, closely resembling what the human eye perceives. While most videos still adhere to the SDR (Standard Dynamic Range) standard, there is a significant market demand for upgrading to HDR. Therefore, this feature will be integrated into future versions.
Terminology:
SDR:
SDR stands for Standard Dynamic Range, which is the most common display technology used in traditional televisions and monitors. Most movies and television shows we watch utilize this technology, capable of displaying approximately 16 million colors with brightness levels ranging between 100-300 nits.
HDR:
HDR stands for High Dynamic Range, which can display up to a billion colors and offers brightness levels from 1,000 to 10,000 nits. However, this display technology requires specific playback equipment, as standard devices generally do not support HDR.
HDR is further divided into various standards, such as HDR10, HDR10+, and Dolby Vision. To illustrate, it is akin to the differences between Samsung and Apple—our standards and configurations differ, yet we are all categorized under the term "smartphone." The current update supports the conversion of SDR to HDR10, with plans to introduce support for Dolby Vision in future updates.
Tools to enhance SDR video to HDR
Converting HDR video to SDR video is relatively much easier, as it simply involves reducing the color gamut. There are many software products on the market that perform this task quite well. However, enhancing SDR video to HDR or even Dolby Vision is considerably more challenging. This is because we need AI algorithms to process each frame of the video, supplementing the color gamut to achieve as close to native HDR effects as possible, rather than just applying basic color grading.
Most products currently on the market that claim to support enhancing SDR video to HDR use LUT models. This method simply applies a generic model to uniformly color-grade all videos, resulting in a quality that is far from that of native HDR video. The only software product that has been released and verified in the market to enhance SDR to HDR is UniFab. Launched in 2023, UniFab has undergone a year of model algorithm iterations, and it now supports enhancing SDR video to HDR10 on 40 series graphics cards, taking only the same duration as the original video.
Although Topaz claims it will release an SDR to HDR model in the second half of 2024, based on the current beta version, we have found that there is a significant gap in processing speed and effectiveness compared to UniFab.
UniFab, as the world's only software to truly enhance SDR videos to HDR with AI, can provide the following features:
Support for Converting SDR Videos to HDR:
Conversion of input SDR videos to 720p HDR videos.
Conversion of input SDR videos to HDR videos matching the source resolution (720p to 720p, 1080p to 1080p, and videos above 1080p converted to 1080p).
Note: Conversion from 720p SDR videos to 1080p HDR videos is not supported, as resolution cannot be increased, only decreased.
Options for Two Color Spaces:
HDR DCI-P3
HDR Rec.2020
Summary
We believe that with the gradual popularization of HDR shooting and playback devices, the demand in the market for enhancing SDR to HDR will continue to grow. We anticipate that more and more products will emerge during that time, and we can look forward to further iterations and improvements from UniFab.