Portrait Mode is a popular feature on modern smartphones, making it super easy for you to capture a photo with a blurry background effect. Google has included it with its past few Pixel flagships, and this week it went into detail on how it improved Portrait Mode with its newest model, the Pixel 4.
First up, the addition of dual rear cameras to the Pixel 4 helped to give the new phone a better Portrait Mode. The two cams on the back of the Pixel 4 are 13mm apart, much farther than the dual-pixel baseline, which makes it easier for the phone to estimate the depth of far away objects.
Those dual cameras work alongside the dual-pixels, which were present in previous Pixel phones. The dual-pixels work by splitting every pixel in half so that each half pixel sees a different half of the main lens' aperture. Reading each half-pixel image separately gives you two slightly different views of the scene and is used to help estimate depth as well.
Google also worked to improve the bokeh, or the background blur, of Portrait Mode photos on the Pixel 4. Previously, Google would replace each pixel in the original image with a translucent disk with a size based on depth. This process was performed after the tone mapping, which is the process of raw sensor data being converted to an image you can see on your phone's screen. However, this tone mapping process loses some information about how bright objects actually were in the scene.
With the Pixel 4, Google is merging the raw image data produced by HDR+ and then applying tone mapping. This helps to give you brighter and more obvious bokeh discs that are closer to what a full on SLR camera can produce. Plus, the background is saturated in the same way as the foreground of your photo.
The addition of a second camera to the back of the Pixel 4 was big because it was the first time that a Google Pixel phone got a second camera, giving owners a telephoto zoom lens. Now we know that that second cam also helped to improve Portrait Mode. With how popular Portrait Mode has become on smartphones, it's good to see Google continue to do work to improve the feature on its Pixel devices, and this week's deep dive from Google is an interesting look at what the company did to make Portrait Mode better.
How often do you take Portrait Mode photos?
