People with low vision who use screen magnifiers to interact with
computing devices find it very challenging to interact with dynamically
changing digital content such as videos, since they do not
have the luxury of time to manually move, i.e., pan the magnifier
lens to different regions of interest (ROIs) or zoom into these ROIs
before the content changes across frames.
In this paper, we present SViM, a first of its kind screen-magnifier
interface for such users that leverages advances in computer vision,
particularly video saliency models, to identify salient ROIs in videos.
SViM’s interface allows users to zoom in/out of any point of interest,
switch between ROIs via mouse clicks and provides assistive
panning with the added flexibility that lets the user explore other
regions of the video besides the ROIs identified by SViM.
Subjective and objective evaluation of a user study with 13 low
vision screen magnifier users revealed that overall the participants
had a better user experience with SViM over extant screen magnifiers,
indicative of the former’s promise and potential for making
videos accessible to low vision screen magnifier users.
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A saliency-driven video magnifier for people with low vision
Consuming video content poses significant challenges for many screen magnifier users, which is the “go to” assistive technology for people with low vision. While screen magnifier software could be used to achieve a zoom factor that would make the content of the video visible to low-vision users, it is oftentimes a major challenge for these users to navigate through videos. Towards making videos more accessible for low-vision users, we have developed the SViM video magnifier system [6]. Specifically, SViM consists of three different magnifier interfaces with easy-to-use means of interactions. All three interfaces are driven by visual saliency as a guided signal, which provides a quantification of interestingness at the pixel-level. Saliency information, which is provided as a heatmap is then processed to obtain distinct regions of interest. These regions of interests are tracked over time and displayed using an easy-to-use interface. We present a description of our overall design and interfaces.
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- Award ID(s):
- 1805076
- NSF-PAR ID:
- 10186665
- Date Published:
- Journal Name:
- 17th Web for All Conference
- Page Range / eLocation ID:
- 1 to 2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3371300.3383356
