Pixelworks designs, develops and markets visual display processing semiconductors,
intellectual property cores, software and custom application specific integrated
circuits ("ASIC") solutions for high-quality energy efficient video
applications. In addition, we offer a suite of solutions for advanced media
processing and the efficient delivery and streaming of video.
We enable worldwide manufacturers to offer leading-edge consumer electronics
and professional display products, as well as video delivery and streaming solutions
for content service providers. Our core visual display processing technology
intelligently processes digital images and video from a variety of sources and
optimizes the content for a superior viewing experience. Pixelworks’ video
coding technology reduces storage requirements, significantly reduces bandwidth
constraint issues and converts content between multiple formats to enable seamless
delivery of video, including over-the-air (OTA) streaming, while also maintaining
end-to-end content security.
The rapid growth in video-capable consumer devices, especially mobile, has
increased the demand for visual display processing and video delivery technology
in recent years. Our technologies can be applied to a wide range of devices
from large-screen projectors to low-power mobile tablets, smartphones, high-quality
video infrastructure equipment and streaming devices. Our products are architected
and optimized for power, cost, bandwidth, and overall system performance, according
to the requirements of the specific application. Our primary target markets
include digital projection systems, tablets, smartphones, and OTA streaming
devices.
High-Resolution Displays
Display technologies have recently begun to transition from an era of higher
resolutions, response times and frame rates, with lower power and thinner form
factors, to one focused on higher contrast and more colors.
In mobile devices, Apple Inc. has brought wide color gamut to many of their
devices including the iPhone, iPad Pro, MacBook Pro and iMac. These devices
deliver the same color gamut used in digital cinema theatres ("DCI-P3").
Meanwhile, television ("TV") manufacturers including Samsung, Sony
and LG are bringing high contrast, high brightness (High Dynamic Range or "HDR")
TVs based on OLED and local-dimming LCD panels to the living room. Furthermore,
premium smartphones and some tablets from Apple, Samsung, Sony, LG and Huawei
now include HDR as a standard feature.
Hardware improvements in color and contrast are of little value without content
that can take advantage of them. In fact, a significant gap now exists between
the vast majority of video content available to consumers, and these emerging
display devices.
Contrast and Brightness: Almost all movies available to consumers today use
the "Rec.709" ITU standard format. This format defines brightness
levels up to around 100 "nits" (a standard measure of brightness),
whereas HDR TVs are five to ten times brighter (from 540 nits upwards). Most
mobile devices support over 400 nits and sometimes over 600 nits.
Color Gamut: DCI-P3 has a 25% larger color gamut than Rec.709.
Frame Rate: Most movies are available in 24 or 25 frames per second, a rate
at which the human eye still perceives judder, but cannot identify individual
still images or frames and sees a video instead. Mobile devices on the other
hand have displays that run at 60 frames per second, and TVs commonly display
120 frames per second - frame rates at which the eye perceives smooth motion.
In addition to the display frame rate discrepancy, the transmission rates vary
based on various factors such as available bandwidth. Standard frame rate conversion
requires the original content frames being repeated or dropped in order to match
the frame rate of the display. This causes the video to appear to judder. Judder
is a common problem in video systems and occurs when there is a sudden jump
or discontinuity in motion from one frame of a motion video sequence to the
next. This can be caused by content being created at a frame rate per second
that is too low, or the original content frames are being repeated or dropped
in order to match either a transmission standard or the playback frame rate
of the display.
Resolution: Finally, TVs have achieved 4k resolutions (3840x2160) and mobile
devices commonly achieve 2560x1440, and while some content is available in 4k
resolution, most movies are only available in FHD or HD resolutions (typically
1920x1080 and 1280x720 respectively).
This gap between display capabilities and available content brings significant
challenges to video display device manufacturers. Sophisticated video processing
is required to accurately reproduce the intended video on today’s displays.
For example, Sony adds their proprietary "4K HDR Processor X1™"
to their latest TV sets and Samsung adds their "mDNIe™" video
processors to their mobile phones.
Content formats are evolving to take advantage of these display improvements.
For example, Dolby introduced the “Dolby Vision™” format for
movies and devices, in order to allow consumers to realize the benefits of HDR
and wide color gamut. The industry standards body Society of Motion Picture
& Television Engineers, released a format specification known as "HDR10"
that similarly bridges the gap in contrast and color between content and devices.
The Ultra-HD Blu-ray disk format and streaming services such as Netflix and
Amazon Video now support 4k HDR, aided by improved compression standards such
as H.265.
Managing many content formats across a rapidly evolving range of displays is
a significant and growing challenge. Older content tends to not get upgraded
to the newer formats, yet consumers expect all content to display correctly.
As the number of content formats grows, the technology of video processing becomes
increasingly complex.
Bridging the gap in color, contrast and resolution, while delivering the intent
of the content creator, requires sophisticated algorithms and hardware circuits.
However, frame-rate and motion incompatibilities require a significantly higher
level of processing and more sophisticated algorithms in order to avoid creating
new problems. Most TVs today include frame-rate conversion chips, but many reviewers
complain about artifacts such as halos, breakup in the image and the so-called
"soap opera effect". Unfortunately, without frame-rate conversion
the video can appear to have judder and blur at levels that have increased substantially
as a result of the improvements in contrast, color and detail.
In addition to judder, high-resolution displays suffer from softness and smearing
in motion sequences called motion blur. There are numerous causes of motion
blur. The materials used in constructing pixels on the display take a finite
amount of time to transition from one state to another. If this time is too
long, the image does not update swiftly and motion sequences seem to smear or
blur. For example, Hollywood movies, TV shows and other premium content are
usually authored at 24 frames per second or 24Hz. At this frame rate, the brain
can easily notice the transition from one frame to the next. As the brain and
eyes track objects in motion, they have to jump in discrete steps due to the
low frame rate. This stop-start motion is perceived by the brain as motion blur,
reducing the visible clarity and fidelity of objects in motion. Additionally,
when a motion sequence is played on a digital display device, the new updated
frame is drawn over the top of the still visible previous frame. This "hold"
effect is perceived by the brain as blur.
Judder and motion blur artifacts are more noticeable on high contrast, wider
gamut displays, regardless of screen size (for example, a 5-inch smartphone
screen viewed from ten inches away appears to be the same size as a 60-inch
large screen TV viewed from ten feet away). Pixelworks advanced video display
processing provides original equipment manufacturers ("OEMs") with
solutions that avoid or minimize these artifacts and help realize the potential
of their investment in high-resolution displays. We believe the most effective
method for removing both judder and reducing blur is motion estimation/motion
compensation ("MEMC") technology. This technology is based on complex
mathematical algorithms that insert additional, interpolated frames to create
a new, faster sequence of frames that has smooth, continuous motion. This technique
works for virtually all types of panel technology.