When Humans and Technology Collide

The field of Human-Computer Interaction (HCI) has been a critical catalyst in driving computer technology forward. The coolest, most breakthrough technology isn’t worth a thing if people can’t figure out how to use it, and can see the value of it.

Today, we launch another blog, this one about the field of perceptual modeling, which is at the heart of DHCAT 2.0. It’s authored by Philip Corriveau, an experimental psychologist and technologist working in Intel’s User-Centered Design Group in Oregon.

Phil’s work and expertise spans video quality, acoustics studies, as well as constructing perceptual models based on detailed user studies.

First, some introductions. I work at Intel in two capacities: I am Intel’s “Golden Eye” for Media Quality, and I manage a team of a dozen researchers who study a wide range of areas. These include Intel’s Media and Acoustics Perception Lab (MAPL), located in Hillsboro Oregon. There’s also a team focused on User Experience Assessment and another team that focuses on the Usage-to-Requirements translation. This blog will focus on the work the MAPL group has done, and continues to do, which is an interesting blend of technology-based research and basic human perception studies.

Cognitive science and experimental psychology have wide-ranging applications, many of which extend beyond hard core science realms. I am here to introduce you to an entirely new application for this area, which most term “the behavioral sciences.”

Before we dive into the depths of what MAPL does let me tell you a bit about me. I grew up in Ontario Canada, and attended Carleton University in Ottawa, where I got my degree in Bachelors of Science Honors in Psychology in 1990. I started my career with the Communications Research Centre where I began my quest to improve the end-users experience primarily focused first on video quality. The work focused on conducting thousands of tests with real end-users, everyday people, to determine what technology would be adopted for the next North American High Definition (HDTV) Standard. A lot of people are totally unaware that years of work and testing took place to ensure that the standards set now called ATSC was “good enough” for the North American viewing public. The type of testing used in this process is called subjective assessment.

Subjective assessment describes the use of a human end-user to provide feedback in a controlled way on their perception of the quality. There are two classes of subjective assessment, expert and non-expert. With expert assessments, people concerned with the technology are used in the evaluations; for example I am considered to be an expert viewer for video quality. Non-expert assessments are where we use actual intended end-users of the technology who don’t have technical knowledge about video quality or display technology. Researchers use a screening process to be sure that the users evaluated are not disguised experts.

Along with the standardization of HDTV in the early 1990’s, the quest of two related video activities were spurred. One was the development of new codec technology that could provide the same level of “Quality” using fewer bits that the current MPEG-2 brought to the table, and the second much more controversial topic was development and standardization of objective tools that estimate a persons expected visual experience. I was heavily involved in both activities from the end-user side, assessing the elusive value around what we call User Experience (UX).

In 1997, I was a founding member of a consortium that brought together core video from various companies and countries called the Video Quality Experts Group (VQEG, www.vqeg.org). New software full reference evaluation tools were proposed under the category of Video Quality Metrics tools and these are now standardized in the ITU-J144 standard. These tools were meant to displace analog test tools like Peak Signal to Noise Ratio (PSNR) calculations, where testing was simple. Since PSNR was no longer valid in the digital domain, some group had to verify the usefulness of the new tools. The group’s mission is to assess the usefulness and accuracy of these proposed tools and how they should be tested. As an expert in subjective assessment, I co-chaired this group for its first nine years. In 2006, I stepped down to return to my work studying human perception here at Intel.

Intel pays a lot of attention to the perceptual experience that customers get with our products. So much so in fact that they built a state-of-the-art facility in Hillsboro Oregon in 2001 specifically designed to provide a controlled environment for testing of Video, Audio, A/V Sync, Acoustics, Voice and to break new ground in the areas of tactile thermal and pure basic perceptual research. I have been managing and working at this facility for the last six years, driving home the importance of UX for aspects of Intel platforms and products that we make.

When a product reaches end-users, the worlds of technology, software, hardware and the end-user collide headlong into one another. That is not the moment for the product maker to realize that their video quality looks like a snowy day with the antenna turned the wrong way, now is it? And assuming you do achieve “good enough” video quality, how can you demonstrate or articulate that to people in ways that are easy to understand.

For the first few installments, we are going to really zoom in on video-related activities, research and requirements. Since my group’s research in the past few years has centered on understanding and quantifying the video experience, this makes for a logical starting point. So let’s dive in…

First, it is never too early to start considering, understanding and measuring the “good enough” experience. There are many technical terms that are used in the industry like “Just Noticeable Difference”, “Good Enough” and others that can be extremely misleading if taken out of context. Here are some simple questions to consider:

Have you truly looked at the quality of your TV, cable, satellite or DVD player?

Do you know what the perceptual difference should be between your current TV and a new HDTV?

Did you know that there are tools available that are designed to help translate performance to user experience? A great example of one that I worked on is DHCAT 2.0, which you can order from ICF for free. Two Video Quality Metric (VQM) tools are available from the Institute for Telecommunication Sciences, and it can be found here.

Did you know that there are limits to the human perceptual system dealing with resolution?

In the next blog we will dive into the playback portion of DHCAT 2.0, where my team conducted the first-ever experiments at Intel to truly map a measurable quantity to user experience.

Got questions? I encourage you to head over to the ICF forums and post them there.