Google on Wednesday announced its own Black Friday deals, offering buyers various discounts on almost all the products it makes under the Home, Chromecast, and Nest brands. The Pixel 3 and Pixel Slate devices that were unveiled just last month aren’t part of this year’s Black Friday sale at Google, but you do get to save $300 on the old Pixelbook, which is still the best Chromebook on the planet. You’ll receive three months of YouTube TV for free with your Chromebook purchase.

Death of the Nexus: Final guaranteed OTA updates hit Nexus 6P and 5X

Nov. 7th 2018

As part of Google’s three-year update plan, the last Nexus devices have now received the final guaranteed OTA update. That means that build number OPM7.181105.004 will be the final official build on both the Nexus 6P and the Nexus 5X and signals the true death of the Nexus line.

While all generations of Google’s Pixel lineup have gotten updates to Android Pie, the Nexus 6P and Nexus 5X saw their final major platform updates with Android 8.1 Oreo. However, for a full year after, Google has been obligated to push security updates to these devices, and that obligation ended following this week’s November security patch. Of course, that doesn’t mean Google can’t push another update, it’s just not promised that the company will do so.

Samsung’s Top-Secret Galaxy S Phone Is a 5G Monster With Six Cameras

Nov. 20, 2018 9:22 a.m. ET

SEOUL— Samsung Electronics Co. is planning a major technological upgrade for its 10th anniversary flagship phones next year, including next-generation 5G network speeds, bigger screens and more cameras, according to people familiar with the matter.

As with rival Apple Inc.’s 10th anniversary iPhone offerings last year, Samsung’s 10-year reboot of its premium smartphone lineup is seeking to dazzle consumers with more ambition than in years past, these people said, part of a bid by the South Korean technology giant to reverse a recent sales slump.

Samsung, the world’s largest smartphone maker by volume, is preparing three versions of its next flagship Galaxy S10 smartphone, with displays that range in size from 5.8 inches to 6.4 inches, the people said, versus two variants in previous years. Those three phones are set to debut in February next year, they added.

In addition, the South Korean technology giant is developing a fourth variant of the Galaxy S10 that will be 5G-enabled and is internally code-named “Beyond X,” some of these people said.

The 5G phone, slated for a spring release in the U.S. and South Korea, would sport an even larger screen, measuring 6.7 inches diagonally, and pack in a whopping six cameras—two in the front and four in the back, these people said, which promise richer photos and better spatial perception.

After several years of declining sales of smartphones, its biggest moneymaker for many years, Samsung needs a big hit next year.

The company’s devices account for one out of every five smartphones shipped globally, but it suffered a major handset sales tumble this year. The smartphone’s overhaul will test consumers’ willingness to ditch their years-old devices for ones that offer flashier features—for a higher price tag.

. . . .

To stage its comeback, Samsung saved up several new features to set its 10th anniversary Galaxy S smartphone apart.

Samsung is planning a mid-February event where it will unveil at least the feature-heavy 5G Galaxy S phone, according to a person familiar with the matter.

The handset’s release date would be pegged to whenever wireless carriers could launch 5G service, according to people familiar with the matter, which is expected by next spring.

Samsung has held discussions with Verizon Communications Inc., AT&T Inc. and T-Mobile US Inc., as well as large South Korean carriers, though no final decisions have been made, according to these people. Samsung is in discussions with Verizon about a potential exclusive distribution arrangement, though the terms and length of that arrangement aren’t yet final, some of these people said.

With 5G, Samsung is expected to enjoy a sizable lead over Apple’s iPhone, which analysts forecast won’t be capable of supporting 5G until 2020.

The three Galaxy S10 handsets scheduled for an earlier release than the 5G phone bear the internal code names “Beyond 0,” “Beyond 1” and “Beyond 2,” according to people familiar with the matter.

They would each have between three and five cameras in total, based on current plans, according to one of these people.

A feature considered for some phones is “reverse wireless charging,” in which a Samsung handset could be used to recharge other devices by placing them together, according to people familiar with the matter.

The timing, design and phone features for all the devices could change since decisions are still being finalized, according to people familiar with the matter.

Separately, Samsung is also set to release early next year its first ever foldable-screen device, which opens like a book and boasts a 7.3-inch display. Internally, Samsung executives are debating the foldable phone’s name, with “Samsung Flex” and the “Galaxy Flex” emerging as two candidates, though the decision is far from final, according to a person familiar with the matter.

But even with the new launches, Samsung will face challenges in a smartphone industry dealing with consumers holding on to their devices longer and economic uncertainty brought on by global trade turmoil, analysts said.

Night Sight: Seeing in the Dark on Pixel Phones

Wednesday, November 14, 2018
Posted by Marc Levoy, Distinguished Engineer and Yael Pritch, Staff Software Engineer

Night Sight is a new feature of the Pixel Camera app that lets you take sharp, clean photographs in very low light, even in light so dim you can't see much with your own eyes. It works on the main and selfie cameras of all three generations of Pixel phones, and does not require a tripod or flash. In this article we'll talk about why taking pictures in low light is challenging, and we'll discuss the computational photography and machine learning techniques, much of it built on top of HDR+, that make Night Sight work.Left: iPhone XS (full resolution image here). Right: Pixel 3 Night Sight (full resolution image here).Why is Low-light Photography Hard?
Anybody who has photographed a dimly lit scene will be familiar with image noise, which looks like random variations in brightness from pixel to pixel. For smartphone cameras, which have small lenses and sensors, a major source of noise is the natural variation of the number of photons entering the lens, called shot noise. Every camera suffers from it, and it would be present even if the sensor electronics were perfect. However, they are not, so a second source of noise are random errors introduced when converting the electronic charge resulting from light hitting each pixel to a number, called read noise. These and other sources of randomness contribute to the overall signal-to-noise ratio (SNR), a measure of how much the image stands out from these variations in brightness. Fortunately, SNR rises with the square root of exposure time (or faster), so taking a longer exposure produces a cleaner picture. But it’s hard to hold still long enough to take a good picture in dim light, and whatever you're photographing probably won't hold still either.

In 2014 we introduced HDR+, a computational photography technology that improves this situation by capturing a burst of frames, aligning the frames in software, and merging them together. The main purpose of HDR+ is to improve dynamic range, meaning the ability to photograph scenes that exhibit a wide range of brightnesses (like sunsets or backlit portraits). All generations of Pixel phones use HDR+. As it turns out, merging multiple pictures also reduces the impact of shot noise and read noise, so it improves SNR in dim lighting. To keep these photographs sharp even if your hand shakes and the subject moves, we use short exposures. We also reject pieces of frames for which we can't find a good alignment. This allows HDR+ to produce sharp images even while collecting more light.

How Dark is Dark?
But if capturing and merging multiple frames produces cleaner pictures in low light, why not use HDR+ to merge dozens of frames so we can effectively see in the dark? Well, let's begin by defining what we mean by "dark". When photographers talk about the light level of a scene, they often measure it in lux. Technically, lux is the amount of light arriving at a surface per unit area, measured in lumens per meter squared. To give you a feeling for different lux levels, here's a handy table:

Smartphone cameras that take a single picture begin to struggle at 30 lux. Phones that capture and merge several pictures (as HDR+ does) can do well down to 3 lux, but in dimmer scenes don’t perform well (more on that below), relying on using their flash. With Night Sight, our goal was to improve picture-taking in the regime between 3 lux and 0.3 lux, using a smartphone, a single shutter press, and no LED flash. To make this feature work well includes several key elements, the most important of which is to capture more photons.

Capturing the Data
While lengthening the exposure time of each frame increases SNR and leads to cleaner pictures, it unfortunately introduces two problems. First, the default picture-taking mode on Pixel phones uses a zero-shutter-lag (ZSL) protocol, which intrinsically limits exposure time. As soon as you open the camera app, it begins capturing image frames and storing them in a circular buffer that constantly erases old frames to make room for new ones. When you press the shutter button, the camera sends the most recent 9 or 15 frames to our HDR+ or Super Res Zoom software. This means you capture exactly the moment you want — hence the name zero-shutter-lag. However, since we're displaying these same images on the screen to help you aim the camera, HDR+ limits exposures to at most 66ms no matter how dim the scene is, allowing our viewfinder to keep up a display rate of at least 15 frames per second. For dimmer scenes where longer exposures are necessary, Night Sight uses positive-shutter-lag (PSL), which waits until after you press the shutter button before it starts capturing images. Using PSL means you need to hold still for a short time after pressing the shutter, but it allows the use of longer exposures, thereby improving SNR at much lower brightness levels.

The second problem with increasing per-frame exposure time is motion blur, which might be due to handshake or to moving objects in the scene. Optical image stabilization (OIS), which is present on Pixel 2 and 3, reduces handshake for moderate exposure times (up to about 1/8 second), but doesn’t help with longer exposures or with moving objects. To combat motion blur that OIS can’t fix, the Pixel 3’s default picture-taking mode uses “motion metering”, which consists of using optical flow to measure recent scene motion and choosing an exposure time that minimizes this blur. Pixel 1 and 2 don’t use motion metering in their default mode, but all three phones use the technique in Night Sight mode, increasing per-frame exposure time up to 333ms if there isn't much motion. For Pixel 1, which has no OIS, we increase exposure time less (for the selfie cameras, which also don't have OIS, we increase it even less). If the camera is being stabilized (held against a wall, or using a tripod, for example), the exposure of each frame is increased to as much as one second. In addition to varying per-frame exposure, we also vary the number of frames we capture, 6 if the phone is on a tripod and up to 15 if it is handheld. These frame limits prevent user fatigue (and the need for a cancel button). Thus, depending on which Pixel phone you have, camera selection, handshake, scene motion and scene brightness, Night Sight captures 15 frames of 1/15 second (or less) each, or 6 frames of 1 second each, or anything in between.1

Here’s a concrete example of using shorter per-frame exposures when we detect motion:Left: 15-frame burst captured by one of two side-by-side Pixel 3 phones. Center: Night Sight shot with motion metering disabled, causing this phone to use 73ms exposures. The dog’s head is motion blurred in this crop. Right: Night Sight shot with motion metering enabled, causing this phone to notice the motion and use shorter 48ms exposures. This shot has less motion blur. (Mike Milne)And here’s an example of using longer exposure times when we detect that the phone is on a tripod:Left: Crop from a handheld Night Sight shot of the sky (full resolution image here). There was slight handshake, so Night Sight chose 333ms x 15 frames = 5.0 seconds of capture. Right: Tripod shot (full resolution image here). No handshake was detected, so Night Sight used 1.0 second x 6 frames = 6.0 seconds. The sky is cleaner (less noise), and you can see more stars. (Florian Kainz)Alignment and Merging
The idea of averaging frames to reduce imaging noise is as old as digital imaging. In astrophotography it's called exposure stacking. While the technique itself is straightforward, the hard part is getting the alignment right when the camera is handheld. Our efforts in this area began with an app from 2010 called Synthcam. This app captured pictures continuously, aligned and merged them in real time at low resolution, and displayed the merged result, which steadily became cleaner as you watched.

Night Sight uses a similar principle, although at full sensor resolution and not in real time. On Pixel 1 and 2 we use HDR+'s merging algorithm, modified and re-tuned to strengthen its ability to detect and reject misaligned pieces of frames, even in very noisy scenes. On Pixel 3 we use Super Res Zoom, similarly re-tuned, whether you zoom or not. While the latter was developed for super-resolution, it also works to reduce noise, since it averages multiple images together. Super Res Zoom produces better results for some nighttime scenes than HDR+, but it requires the faster processor of the Pixel 3.

By the way, all of this happens on the phone in a few seconds. If you're quick about tapping on the icon that brings you to the filmstrip (wait until the capture is complete!), you can watch your picture "develop" as HDR+ or Super Res Zoom completes its work.

Other Challenges
Although the basic ideas described above sound simple, there are some gotchas when there isn't much light that proved challenging when developing Night Sight:

1. Auto white balancing (AWB) fails in low light.

Humans are good at color constancy — perceiving the colors of things correctly even under colored illumination (or when wearing sunglasses). But that process breaks down when we take a photograph under one kind of lighting and view it under different lighting; the photograph will look tinted to us. To correct for this perceptual effect, cameras adjust the colors of images to partially or completely compensate for the dominant color of the illumination (sometimes called color temperature), effectively shifting the colors in the image to make it seem as if the scene was illuminated by neutral (white) light. This process is called auto white balancing (AWB).

The problem is that white balancing is what mathematicians call an ill-posed problem. Is that snow really blue, as the camera recorded it? Or is it white snow illuminated by a blue sky? Probably the latter. This ambiguity makes white balancing hard. The AWB algorithm used in non-Night Sight modes is good, but in very dim or strongly colored lighting (think sodium vapor lamps), it’s hard to decide what color the illumination is.

To solve these problems, we developed a learning-based AWB algorithm, trained to discriminate between a well-white-balanced image and a poorly balanced one. When a captured image is poorly balanced, the algorithm can suggest how to shift its colors to make the illumination appear more neutral. Training this algorithm required photographing a diversity of scenes using Pixel phones, then hand-correcting their white balance while looking at the photo on a color-calibrated monitor. You can see how this algorithm works by comparing the same low-light scene captured using two ways using a Pixel 3:Left: The white balancer in the Pixel’s default camera mode doesn't know how yellow the illumination was on this shack on the Vancouver waterfront (full resolution image here). Right: Our learning-based AWB algorithm does a better job (full resolution image here). (Marc Levoy)2. Tone mapping of scenes that are too dark to see.

The goal of Night Sight is to make photographs of scenes so dark that you can't see them clearly with your own eyes — almost like a super-power! A related problem is that in very dim lighting humans stop seeing in color, because the cone cells in our retinas stop functioning, leaving only the rod cells, which can't distinguish different wavelengths of light. Scenes are still colorful at night; we just can't see their colors. We want Night Sight pictures to be colorful - that's part of the super-power, but another potential conflict. Finally, our rod cells have low spatial acuity, which is why things seem indistinct at night. We want Night Sight pictures to be sharp, with more detail than you can really see at night.

For example, if you put a DSLR camera on a tripod and take a very long exposure — several minutes, or stack several shorter exposures together — you can make nighttime look like daytime. Shadows will have details, and the scene will be colorful and sharp. Look at the photograph below, which was captured with a DSLR; it must be night, because you can see the stars, but the grass is green, the sky is blue, and the moon casts shadows from the trees that look like shadows cast by the sun. This is a nice effect, but it's not always what you want, and if you share the photograph with a friend, they'll be confused about when you captured it.Yosemite valley at nighttime, Canon DSLR, 28mm f/4 lens, 3-minute exposure, ISO 100. It's nighttime, since you can see stars, but it looks like daytime (full resolution image here). (Jesse Levinson)Artists have known for centuries how to make a painting look like night; look at the example below.2
A Philosopher Lecturing on the Orrery, by Joseph Wright of Derby, 1766 (image source: Wikidata). The artist uses pigments from black to white, but the scene depicted is evidently dark. How does he accomplish this? He increases contrast, surrounds the scene with darkness, and drops shadows to black, because we cannot see detail there.We employ some of the same tricks in Night Sight, partly by throwing an S-curve into our tone mapping. But it's tricky to strike an effective balance between giving you “magical super-powers” while still reminding you when the photo was captured. The photograph below is particularly successful at doing this.Pixel 3, 6-second Night Sight shot, with tripod (full resolution image here). (Alex Savu)How Dark can Night Sight Go?
Below 0.3 lux, autofocus begins to fail. If you can't find your keys on the floor, your smartphone can't focus either. To address this limitation we've added two manual focus buttons to Night Sight on Pixel 3 - the "Near" button focuses at about 4 feet, and the "Far" button focuses at about 12 feet. The latter is the hyperfocal distance of our lens, meaning that everything from half of that distance (6 feet) to infinity should be in focus. We’re also working to improve Night Sight’s ability to autofocus in low light. Below 0.3 lux you can still take amazing pictures with a smartphone, and even do astrophotography as this blog post demonstrates, but for that you'll need a tripod, manual focus, and a 3rd party or custom app written using Android's Camera2 API.

How far can we take this? Eventually one reaches a light level where read noise swamps the number of photons gathered by that pixel. There are other sources of noise, including dark current, which increases with exposure time and varies with temperature. To avoid this biologists know to cool their cameras well below zero (Fahrenheit) when imaging weakly fluorescent specimens — something we don’t recommend doing to your Pixel phone! Super-noisy images are also hard to align reliably. Even if you could solve all these problems, the wind blows, the trees sway, and the stars and clouds move. Ultra-long exposure photography is hard.

How to Get the Most out of Night Sight
Night Sight not only takes great pictures in low light; it's also fun to use, because it takes pictures where you can barely see anything. We pop up a “chip” on the screen when the scene is dark enough that you’ll get a better picture using Night Sight, but don't limit yourself to these cases. Just after sunset, or at concerts, or in the city, Night Sight takes clean (low-noise) shots, and makes them brighter than reality. This is a "look", which seems magical if done right. Here are some examples of Night Sight pictures, and some A/B comparisons, mostly taken by our coworkers. And here are some tips on using Night Sight:

- Night Sight can't operate in complete darkness, so pick a scene with some light falling on it.
- Soft, uniform lighting works better than harsh lighting, which creates dark shadows.
- To avoid lens flare artifacts, try to keep very bright light sources out of the field of view.
- To increase exposure, tap on various objects, then move the exposure slider. Tap again to disable.
- To decrease exposure, take the shot and darken later in Google’s Photos editor; it will be less noisy.
- If it’s so dark the camera can’t focus, tap on a high-contrast edge, or the edge of a light source.
- If this won’t work for your scene, use the Near (4 feet) or Far (12 feet) focus buttons (see below).
- To maximize image sharpness, brace your phone against a wall or tree, or prop it on a table or rock.
- Night Sight works for selfies too, as in the A/B album, with optional illumination from the screen itself.Manual focus buttons (Pixel 3 only).Night Sight works best on Pixel 3. We’ve also brought it to Pixel 2 and the original Pixel, although on the latter we use shorter exposures because it has no optical image stabilization (OIS). Also, our learning-based white balancer is trained for Pixel 3, so it will be less accurate on older phones. By the way, we brighten the viewfinder in Night Sight to help you frame shots in low light, but the viewfinder is based on 1/15 second exposures, so it will be noisy, and isn't a fair indication of the final photograph. So take a chance — frame a shot, and press the shutter. You'll often be surprised!

Acknowledgements
Night Sight was a collaboration of several teams at Google. Key contributors to the project include: from the Gcam team Charles He, Nikhil Karnad, Orly Liba, David Jacobs, Tim Brooks, Michael Milne, Andrew Radin, Navin Sarma, Jon Barron, Yun-Ta Tsai, Jiawen Chen, Kiran Murthy, Tianfan Xue, Dillon Sharlet, Ryan Geiss, Sam Hasinoff and Alex Schiffhauer; from the Super Res Zoom team Bart Wronski, Peyman Milanfar and Ignacio Garcia Dorado; from the Google camera app team Gabriel Nava, Sushil Nath, Tim Smith , Justin Harrison, Isaac Reynolds and Michelle Chen.
1 By the way, the exposure time shown in Google Photos (if you press "i") is per-frame, not total time, which depends on the number of frames captured. You can get some idea of the number of frames by watching the animation while the camera is collecting light. Each tick around the circle is one captured frame.↩

2 For a wonderful analysis of these techniques, look at von Helmholtz, "On the relation of optics to painting" (1876).↩