The Portrait Expert: OPPO’s Perfect Combination Of Hardware And Algorithm
The OPPO Reno Series continues to provide industry-leading smartphone shooting capabilities to users and the new Series, Reno7, also known as The Portrait Expert, is no different. The brand new Reno7 Pro 5G is powered by two flagship imaging sensors — the IMX709 and the IMX766 — has perfectly combined professional hardware with professional algorithms to create an all-new breakthrough in portrait imaging.
OPPO RENO7
NEW-GEN RGBW SENSOR POWERED BY THE REVOLUTIONARY QUADRA BINNING ALGORITHM
The art of capturing light is known as photography. Camera manufacturers have been striving for bigger light intake and purer light for over a century, because the more light captured the sharper the image created by translating the light signal into a digital signal. The smartphone industry has been preoccupied with how to enhance light intake for years.
RGBW technology, an adjusted and modified version of RGGB pixel arrangement of Bayer array, has become one of the main approaches in the field of image technology in recent years. However, due to problems such as manufacturing process, the limited computational power of the sensors, and signal cross-talk, images taken using traditional RGBW pixel array sensors are often prone to chromatic aberrations and false colors. Therefore, RGBW sensors have never been considered the mainstream option for enhancing sensor sensitivity.
OPPO never stopped and continued their research in sensor technologies in order to find the best way to increase light sensitivity. The most difficult thing for OPPO’s R&D team was to figure out how to employ the W in the pixel layout while avoiding the previous issues. And the most important thing to do after designing the W and RGB combo pattern was to finish the conversion algorithm.
OPPO’s imaging R&D team never gave up when challenges arose. In 2019, the team was inspired by an academic paper. Hence, they creatively proposed to develop the Quadra Binning Algorithm by adding two W pixels to each R, G, and B pixel so that each pixel would be capable of detecting and recognizing red, green, blue, and white signals. They also applied DTI (Deep Trench Isolation) technology so that each pixel could function independently without influencing its neighbors. This resulted in less electronic signal cross-talk, which ultimately led to cleaner images and more accurate colors. After three years of studying and refining the RGBW technology and investing tens of millions of dollars in the process, the tireless effort of over three hundred OPPO imaging engineers finally paid off, bringing OPPO a revolutionary breakthrough and 87 patents.
THE INDUSTRY’S FIRST TO EMBED SELF-DEVELOPED ALGORITHMS ONTO THE SENSOR HARDWARE
The strengthening and verification of OPPO’s self-developed Quadra Binning Algorithm Real Time Logistics (RTL) was finished in April 2020. Four months later, the RTL of the Quadra Binning Algorithm was successfully integrated with the RGBW sensor to build the self-developed RGBW image fusion unit. The sensor was successfully launched with OPPO’s proprietary RGBW image fusion unit, and was named as IMX709 Ultra-Sensing Sensor. OPPO’s Imaging R&D team also worked closely with chip manufacturers including Qualcomm and MediaTek to conduct compatibility tests on the IMX709 to ensure its compatibility. Compared with the IMX615, IMX709 brings 60% more light and delivers 35% less noise.
Additionally, OPPO’s imaging R&D team decided to tread in uncharted waters by using 22nm process technology on IMX709. Compared to 40nm technology, 22nm allows for 330% more transistors and an increase in manufacturing accuracy of 45%. When operating under the same conditions, the IMX709 consumes 30% less power than if it were built on 40nm technology, giving the IMX709 the best power-to-performance ratio of any flagship front camera image sensor.
OPPO AND SONY COLLABORATED ON THE CREATION OF A LARGE 1/1.56-INCH SENSOR
OPPO and Sony co-designed the IMX766 which measures 1/1.56 inch in size, supports 50-megapixel resolution, and features 1μm pixels (or 2μm pixels using OPPO’s self-developed Quadra Binning algorithm). The main camera supports all-pixel focus 2.0, meaning all pixels can be used to focus. Hence, no matter whether focusing on something big or small, near or far, the IMX766 is always fast and accurate. Same as the IMX709 on the front camera, the IMX766 also supports DOL-HDR from the hardware level. Hence, reducing ghosting effects and enabling real-time HDR video previews on the screen.
DSLR-LIKE PORTRAITS WITH PORTRAIT MODE
With its pro DOF (depth of field) and bokeh algorithms, the Reno7 Series gives a completely natural DOF effect to the background of the portrait images, bringing DSLR-level portrait images to smartphones. In order to recreate professional DOF effects as seen on DSLR cameras, the process of reconstructing the bokeh light spot was the key factor. OPPO imaging engineers optimize the algorithms to delicately reconstruct the bokeh light spot in a way that faithfully mimics the effects as seen on DSLR cameras.
Furthermore, with the help of Portrait Mode, the background saturation and the outline of the bokeh lights are further enhanced. Thus, preventing flat-looking backgrounds and creating images with more depth and realism. Portrait Mode also optimizes the skin tone, helping the portrait subject to stand out while keeping their skin appearing natural.
Filming portrait videos at night and in backlight is one of the biggest challenges for cameras, especially for smartphones. Rendering image brightness, clarity, noise, and portrait processing in dimly lit surroundings is an arduous task for a smartphone’s imaging system. AI Highlight Video runs in the background and does not require users to enable it manually. The algorithm automatically applies the proper presets to optimize videos upon detecting dimly lit or backlit surroundings. So, whether shooting at night or with the bright backlight of a beautiful sunset, AI Highlight Video will capture clearer, brighter, and more vivid portrait videos on both the front and rear cameras.
From the first Reno Series to the latest Reno7 Series, OPPO has never stopped its exploration of imaging technology. With professional hardware and professional algorithms, OPPO brings the Portrait Expert to its global users with the newest OPPO Reno7 Series.
Looking to the future, OPPO will continue to focus on exploring new possibilities in imaging through both hardware and software advancements. The Reno Series will further explore the possibilities of portrait imaging and image quality to bring even more professional portrait photography to users around the world.