Anirudh RegidiDec 07, 2020 13:54:23 IST
Qualcomm’s annual Snapdragon Summit just wrapped up and furnished us with the details of the flagship SoC that will be powering 2021’s most capable Android smartphones.
The flagship SoC in question is called Snapdragon 888 and promises a huge jump in performance over the previous Snapdragon 865 chip that’s been powering phones thus far.
Of note is the new and improved camera system (3x Spectra 580 ISP) and massively upgraded AI chip (Hexagon 780). The 888 also makes use of more powerful CPU cores, supports faster RAM, and finally features an integrated 5G modem. The manufacturing process also sees a shrink to 5 nm.
In terms of capabilities, Qualcomm says that the GPU is 35 percent faster than before, that the AI chip has 1000x lower latency and sees a performance bump from 15 TOPS to 26, and that the new triple ISP system supports larger images and 4K HDR on three cameras simultaneously.
The brand new X60 modem is now integrated — it was a discrete unit on the 865 — which should result in some improvements to efficiency and power consumption.
In sum, this is the largest year-on-year performance bump that Qualcomm has ever offered.
Here’s a quick overview of the chip:
|Model||Snapdragon 865||Snapdragon 888|
|Prime core||1x Cortex A77 @ 2.84 GHz||1x Cortex X1 @ 2.84 GHz|
|big core||3x Cortex A77 @ 2.42 GHz||3x Cortex A78 @ 2.42 GHz|
|LITTLE core||4x Cortex A55 @ 1.8 GHz||4x Cortex A55 @ 1.8 GHz|
|GPU||Adreno 650||Adreno 660|
|DSP||Hexagon 698||Hexagon 780|
|Memory||Up to 2750 MHz LPDDR5||3200 MHz LPDDR5|
|ISP||2x 14-bit Spectra 480||3x 14-bit Spectra 580|
|Single image capture||1x 200 MP / 64 MP ZSL*||1x 200 MP / 84 MP ZSL|
|Multi-image capture||2x 25 MP ZSL||64 MP + 25 MP ZSL / 3x 28 MP ZSL|
|Video||8K 30 / 4K 120 10-bit H.265||8K 30 / 4K 120 10-bit H.265|
|Mfg. Process||7 nm||5 nm|
CPU: New cores and a design that focuses on sustained performance
The SD888 sticks with the triple cluster configuration, featuring one high performance core, three performance cores, and four efficiency cores. This time around, the high performance ‘Prime’ core is the latest Cortex X1 clocked at 2.84 GHz. This core can be clocked to a little over 3 GHz, but Qualcomm says it stuck with 2.84 GHz so as to offer better sustained performance under heavy workloads.
The performance cores also see an upgrade to the new Cortex A78 core (from last year’s A77), but are still clocked at 2.42 GHz for the reasons stated above.
Do note that the 865+ featured a Prime core clocked at 3.09 GHz — vs 2.84 GHz on the regular 865 — so it would be safe to assume that an overclocked 888+ variant will arrive later next year.
The third cluster of 4x Cortex A55 cores appears to have been carried forward as is from last year.
Overall CPU performance has improved by about 25 percent, says Qualcomm, with the focus being on better sustained performance rather than peak performance.
GPU: 35 percent faster and VRS support
Qualcomm’s secret sauce has always been its GPU and DSP (more on that in a bit). While Samsung and Huawei preferred off-the-shelf ARM designs in the past, Qualcomm has, for a while now, been designing its own GPU and DSP chips.
We don’t know much about the inner workings of the new Adreno 660 GPU, but Qualcomm did mention that it is now about 35 percent faster and 20 percent more efficient than last year’s Adreno 650, and that the GPU now supports VRS or variable rate shading.
VRS is a feature that’s only recently arrived to PC graphics cards and game consoles. VRS essentially allows for a scene in a game to render faster by spending less time and effort rendering portions of the scene that would not be significant to the player anyway. For example, areas under deep shadow or in the distance need not be rendered with as much texture detail and colour accuracy as areas that are closer to the player.
Given that the SD865 could already support 120 fps and 144 fps gaming, this bump in graphics performance could be used to significantly improve the quality of in-game graphics.
Other features like QuickTouch help improve touch response, further enhancing the gaming experience.
Hexagon DSP: Massively improved AI performance
Now this is something Qualcomm was very excited to talk about. The Snapdragon 888 features ‘fused AI accelerators’.
Essentially, earlier iterations of the Hexagon DSP (digital signal processor) featured separate scalar, vector, and tensor accelerators — cores that perform specific mathematical operations needed for AI calculations. Each accelerator had its own memory and a pool of shared memory, and the system did work very well, giving Qualcomm a significant lead in AI performance compared to rivals.
This year, Qualcomm completely redesigned the DSP and ‘fused’ the functions of the three accelerators. The result, according to Qualcomm, is a huge improvement in AI performance. This improved AI engine communicates 1000x (yes, one thousand times) faster than before, while consuming less power and nearly doubling performance in certain AI workloads.
Other updates such as a wider memory bus and memory pool have also helped.
Overall, performance has gone up a claimed 73 percent compared to last year’s 865.
The updates to AI performance are, unfortunately, a little harder to comprehend in the real-world. What are tensor operations, for example, and how do they matter?
Well, improvements in AI performance mean that intelligent computing features like intelligent noise suppression (audio and video), real-time object replacement in video, AI-based autofocus, faster image processing, and more can now be a reality for Android.
Camera upgrades: Staggered HDR and concurrent recordings
By far the most interesting bit of news from the event was the mention of staggered HDR support for stills and video.
Before we get to that, let’s first take a look at the hardware upgrades. Primarily, the SD 888 bumps up the total number of ISPs to three. An ISP or image signal processor is the chip that is responsible for processing imaging data from a phone’s cameras. With three independent ISPs (up from two in the 865), Snapdragon 888-powered phones can now, finally, capture images and video from three cameras simultaneously. Apple introduced this feature last year with the iPhone 11 Pro line.
The ISPs now allow for concurrent 28 MP ZSL capture (zero shutter lag). Single camera ZSL capture has been bumped up to 84 MP (from 64 MP), and 200 MP single image captures without ZSL are supported.
ZSL is simply Qualcomm’s term for an image capture mechanism where the sensor actively records data before a shutter press, ensuring that image data is recorded the instant the shutter is pressed, and not after the fact.
Triple camera ZSL capture means you can have stitched images and seamless zoom between, say, an ultra-wide, wide, and tele lens (as Apple has been doing since 2019).
The camera system now allows the capture of 120 12 MP images per second, and autofocus in low light (up to 0.1 lux).
Video recording features remain largely unchanged, with 8K 30 fps and 4K 120 fps with HDR being the highest supported resolutions.
A new AI-based autofocus system claims to improve AF performance by intelligently identifying the subject in a scene and tracking focus appropriately.
The most interesting upgrade, though, is support for staggered HDR.
HDR image/video capture happens when multiple different exposures are captured and stitched together, resulting in an image with more dynamic range (greater detail in bright and dark regions) than a single image would have had.
In regular HDR, the camera shutter captures at least three distinct frames: one underexposed frame, one overexposed frame, and one properly exposed frame. New phones do capture a lot more frames, however, but the point is that each frame is captured as a whole, one complete frame at a time. Recording for the next frame doesn’t start until the previous frame has been recorded and processed.
This is very effective for static objects, but when a scene involves moving objects (dogs, cars, windy weather), there can be some ghosting and blur because of the time it takes to capture individual frames.
Staggered HDR reduces this lag by not waiting for an individual frame to be captured. As and when each line of the sensor is read for one frame, capture for the subsequent frame begins on that line. HDR data is recorded continuously, resulting in much less lag between frames, and thus less motion blur and ghosting.
X60 Modem: Integrated, faster, more efficient
Last year’s SD865 did not include an integrated modem. Qualcomm had their own reasoning for this, and stated that the modem was developed independently and was ready before the 865 was, allowing manufacturers to work on their 5G implementations. Regardless, now that the x60 is integrated into the 888, this should result in lower prices and better performance and power efficiency. Exactly how much of a benefit this is still remains to be seen, however.
The x60 is also claimed to be faster and more efficient than the x50, offering much lower power consumption in edge cases, and adds better support for carrier aggregation, resulting in much higher signal quality and bandwidth.
Additionally, the platform supports WiFi 6, WiFi 6E, and dual radio Bluetooth 5.2 and AptX Adaptive wireless audio.
Misc features: Hypervisors, CAI
An important feature of the Snapdragon 888 is support for hypervisors. A hypervisor is a system for isolating one user space from another, creating multiple secure virtual machines.
In plain English, the hypervisor will allow for, say, a secure work profile on your phone that can function independently of your personal profile. Data from the two profiles will be independently and securely handled. The hypervisor can also be used to completely isolate sensitive apps from the rest of the system.
SD 888 now also supports the CAI or Content Authenticity Initiative standard. Any image you capture via this system contains a cryptographic key that verifies the authenticity of the metadata (location, time of capture, etc.) and that the image hasn’t been manipulated. Any modification changes the key and flags the image as having been manipulated.
In this world of deep fakes and manipulated images, a CAI-stamped image is more likely to be trusted.
Calling all devs!
Pending real-world tests and benchmarks, Qualcomm appears to have surpassed itself this time around. The SD 888 platform is a significant upgrade over last year’s 865, and introduces a number of exciting new features to boot.
It’s a truly impressive upgrade and I’m quite excited to see what 2021’s Android flagships have in store for us. I just hope developers take full advantage of the capabilities afforded to them by the new platform.