Google confirms that Pixel 4 will offer multiple rear cameras
(Digital Photography Review)

Leaked renderings of the upcoming Pixel 4 seem to have prompted Google to get ahead of its own story by tweeting an image of the device well ahead of its expected fall launch date. Prominently featured is a square `bump` that appears to house two rear-facing cameras, a flash and two smaller sensors, one of which is visible if you raise the image`s shadows. We imagine that the small sensor to the right of the flash is a spectral + flicker sensor, something that helps avoid banding with flickering light sources and also helps the auto white balance algorithm estimate the dominant illuminant for better color reproduction. The Pixel 3 has one of these sensors next to its flash, too. The fourth sensor, positioned above and centered between the two main cameras, appears too small to be another camera unit. We`ve often wondered about the future inclusion of a Time-of-Flight (ToF) camera in the Pixel lineup. Competitors like Huawei and Samsung have been adding these sensors to their devices to help with depth mapping. The Pixel 3`s portrait mode images were already among the best from current mobile devices, so we`re interested to see what the addition of a secondary camera - and whatever that additional sensor is - might add up to.