If You Think Xiaomi's 100-Megapixel Camera Phone Will be Revolutionary, Read This

You probably knew this would happen — expected it, even, and now it's finally here. Earlier today, Xiaomi announced at its global event in Beijing, China that its next smartphone under the Redmi moniker would feature a 64-megapixel sensor. While that was already in the pipeline, Xiaomi went one step further and added that it would also introduce a smartphone featuring a 100-megapixel sensor, later this year. The smartphone, of which nothing much is really known, would potentially become the first in the world to breach the 100-megapixel magic figure when it comes to imaging, so naturally, Twitter and the rest of the internet is already buzzing with the possibilities that it might bring.

Not unexpected

First off, don't be too surprised by this move, for a 100-megapixel mobile imaging sensor was in the making for a while now. Earlier this year, Judd Heape, Qualcomm’s senior director of product management for the camera, computer vision and video, revealed over a teleconference with journalists across the world that this was an eventuality. In his very words, "By the end of the year, we should see something over 100MP from a couple of sensor manufacturers." The context of the conference was the Snapdragon Spectra image signal processor (ISP), which is the tiny little bit inside your phone processors that handle the camera and imaging abilities of the smartphone.

Heape's announcement stated that although not tested in the practical world, his company Qualcomm was ready to support image sensors going all the way up to a staggering 192 megapixels. This, as he explained, was theoretical, because of engineering limitations around camera sensor technology, and the additional bits and pieces that it requires. While we explain more of this below, Heape's statement from back in March 2019 clearly states that a 100-megapixel mobile imaging sensor was definitely in the making. Hence, while it certainly is an engineering feat worth applauding, it's not entirely out of the blue, or unexpected.

What it might offer

Heape had even mentioned that 64-megapixel sensors were already on the way in phones. This is something that Xiaomi announced initially today — a shiny new Samsung ISOCELL GW1 image sensor, featuring 64-megapixel maximum output resolution. As you might have guessed, this sensor also comes with a quad pixel array — a technology that Sony and its IMX586 48-megapixel image sensor made popular. Essentially, such sensors break down the conventional large pixel into half-sized, smaller pixels, thereby increasing the pixel count.

In simple terms, what this lets a camera do is reduce the inefficiency of performance in sensors, absorb more of the incident light on a camera, and thereby process a higher level of details. In the 64-megapixel sensor, Samsung uses a particular technology that prevents light from leaking in between pixels, thereby producing even higher details. Add this to a larger sensor size (in-camera parlance, larger sensor = better imaging performance), new colour reproduction technology, automatic ISO calibration depending on light and a new HDR processing unit, and you have a potential winner in your hands.

With the 100-megapixel sensor, expect the fundamental technology to remain the same. While we cannot conclusively state that this will be it (Samsung will certainly have a trick or two up their sleeves for the 100-megapixel unit), the new sensor will likely use the quad pixel array (or pixel binning) technology, combined with a few more advanced features, to produce the magic figure of 100 megapixels.

What a user gets

Standard photographs at the highest setting from a sensor with 100 million pixels would likely range around the 20.5-megapixel mark, which is what Sony and Samsung's sensors of yore had produced already, albeit without pixel binning. The standard JPEG file produced from a sensor ranges around the 16-megapixel mark, which is deemed ideal for present computing standards while accounting for sensor buffer (RAM for cameras), ISP capability, storage size and speed, phone RAM, internet bandwidth and image compression standards. Given that such files can already produce rather brilliant photographs when the intelligent algorithms get the settings correct, your naked eye will likely not see a massive difference with the 100-megapixel photographs.

As Heape had explained, the presence of a zero shutter lag buffer memory means that imaging standards need to be capped at a certain point, and simply increasing the megapixel count really makes no sense. You need to account for frame rates in order to put all of this in a production phone, and unfortunately, even this 100-megapixel sensor would be capped by these engineering limitations.

Interesting, not path-breaking

All of this still does not take away from the upcoming image sensor being a really interesting one to explore further and understand the advancement of imaging technology. In April 2019, Sony unveiled a 100-megapixel full-frame image sensor — something that is more path-breaking since it eats into the territory of the medium format cameras.

As for the 100-megapixel mobile sensor tipped to feature in a Redmi phone later this year, this will likely not be as earth-shattering as you would think, since even with a cropped sensor at software-driven ultra-wide-angle super-resolution images, you would not go beyond the 29-megapixel peak resolution figure at wide aspect ratio, and on flagship phones, 4K video recording at 120 frames per second. Like our sub-head says, the upcoming camera is truly interesting, but it will likely not be a path-breaker in terms of camera innovation.