Accessibility to web images through multiple image resolutions

A method, program and apparatus for providing access to alternate images in an electronic document are provided. The present invention comprises identifying an initial image to be displayed in an electronic document (typically a web page) and then determining if alternate versions of the image are available for display. If alternate versions of the image are available, they are provided within the same electronic document. The alternate images differ from the initial image in size and resolution, allowing users with visual impairments to access larger, higher resolution images. The user accesses the alternate images by means of a selector displayed within the electronic document. When selected, the alternate image replaces the initial image in the electronic document, and the document is reformatted.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to computer network environments. More specifically, the present invention relates to accessing electronic documents.

2. Description of Related Art

Information on the World Wide Web is typically made available by structuring the information into a visual presentation. Hypertext Markup Language (HTML) is used by the web author to define the visual structure. The end user is presented with this information by viewing the information on a computer display, after the information has been rendered into a visual format by a web browser (e.g. Netscape Navigator or Microsoft Internet Explorer).

However, the images displayed by conventional web browsers may not be clear enough for users with visual impairments. Though web users with visual impairments can set a web browser to default to a larger font for readability, it is often desirable for this impaired user to see a larger, more detailed version of an image. Currently, there is no way for the user to know if there is a higher resolution image available on the same web page. With today's web pages, the user must access an alternate version of the image via a link to an alternate web page, or an alternate image file. Current web browsers may allow the user to magnify portions of a web page (including images), but this magnification does not adjust picture resolution, resulting in a grainy image.

Therefore, it would be desirable to have a method for directly accessing alternate sizes of an image, with corresponding adjustments in resolution to maintain sharp picture quality.

SUMMARY OF THE INVENTION

The present invention provides a method, program and apparatus for providing access to alternate images in an electronic document. The present invention comprises identifying an initial image to be displayed in an electronic document (typically a web page) and then determining if alternate versions of the image are available for display. If alternate versions of the image are available, they are provided within the same electronic document. The alternate images differ from the initial image in size and resolution, allowing users with visual impairments to access larger, higher resolution images. The user accesses the alternate images by means of a selector displayed within the electronic document. When selected, the alternate image replaces the initial image in the electronic document, and the document is reformatted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Peripheral Component Interconnect (PCI) bus bridge214connected to I/O bus212provides an interface to PCI local bus216. A number of modems may be connected to PCI bus216. Typical PCI bus implementations will support four PCI expansion slots or add-in connectors. Communications links to network computers108,110, and112inFIG. 1may be provided through modem218and/or network adapter220connected to PCI local bus216through add-in boards.

The data processing system depicted inFIG. 2may be, for example, an IBM RISC/System 6000 system, a product of International Business Machines Corporation in Armonk, N.Y., running the Advanced Interactive Executive (AIX) operating system.

As another example, data processing system300may be a stand-alone system configured to be bootable without relying on some type of network communication interface, whether or not data processing system300comprises some type of network communication interface. As a further example, data processing system300may be a Personal Digital Assistant (PDA) device, which is configured with ROM and/or flash ROM in order to provide non-volatile memory for storing operating system files and/or user-generated data.

Turning next toFIG. 4, a block diagram of a browser program is depicted in accordance with a preferred embodiment of the present invention. Browser400includes a user interface402, which is a graphical user interface (GUI) that allows the user to interface or communicate with browser400. This interface provides for selection of various functions through menus404and allows for navigation through the navigation button406or selections. For example, menu404may allow a user to perform various functions, such as saving a file, opening a new window, displaying a history, and entering a URL. Navigation406allows for a user to navigate various pages and to select web sites or documents for viewing. For example, navigation406may allow a user to see a previous page or a subsequent page relative to the present page. User preferences may be set through preferences408.

Communications410is the mechanism with which browser400receives documents and other resources from a network such as the Internet. Further, communications410is used to send or upload documents and resources onto a network. In the depicted example, communication410uses HTTP. However, other protocols are possible. Documents that are received by browser400are processed by language interpreter412, which includes an HTML unit414. Language interpreter412will process a document for presentation on graphical display418. In particular, HTML statements are processed by HTML unit414for presentation. Browser400also includes cache memory416.

Graphical display418includes layout unit420, rendering unit422, and window management unit424. These units are involved in presenting web pages to a user based on results from language interpretation412.

Browser400is presented as an example of a browser program in which the present invention may be embodied. Browser400is not meant to imply architectural limitations to the present invention. Presently available browsers may include additional functions not shown or may omit functions shown in browser400. As used herein, the term “browser” encompasses any software application used to view or navigate for information or data (i.e. something that assists a user to browse) in a local or distributed data base where the distributed database is typically the Internet or World Wide Web.

It should also be noted that the present invention may also be applied to word processing and desktop publishing applications, as well as any other applications which involve placing images within electronic documents.

The present invention provides a method to make web images more accessible to people who are vision impaired (or want to view a more detailed image) by providing access to multiple-sized versions of an image on a web page. The multiple images are accessed from the web and displayed at the location of the original image when the person desires to see a larger image. This is accomplished without accessing a new web address or changing the rest of the web page's content. Unlike prior art approaches which simply magnify an image without adjusting picture resolution, the present invention allows the user to view a larger image with the proper adjustment in resolution needed to maintain a sharp picture quality. The new image is displayed, along with reflowing of the web page.

The present invention requires an addition to the HTML/XML standards to allows an ALT attribute for the <IMG> tag which can specify multiple images.

Referring toFIG. 5, a pictorial diagram illustrating reflowing of the object text on a web page is depicted in accordance with the present invention. Flow is the manner in which text on a web page is arranged in order to accommodate an image or other object rendered by the browser. Reflowing involves adjusting the text layout to accommodate changes in the size of the image. InFIG. 5, web pages500and510illustrate the reflowing of text required to accommodate the transition from the smaller image501to a larger image511.

This process can be repeated for several sizes of images, until the user reaches the size of image that he finds most readable. When the user is finished viewing the image, he can then reverse the process and bring back the smaller images, again providing more page/screen space for text and other objects.

The present invention provides several advantages:The present invention solves the problem of having to go to a new web page, when the user needs to see a larger, more detailed image.Additional versions of the image may be transmitted while the user is viewing the first image, thereby minimizing perceived transmission time and web URL access time.Once a different size image is downloaded, it is cached along with the web page, allowing for quick changes among the different sizes of images.

In addition, the present invention is useful for easily implementing the common web application of a web page with a thumbnail picture, which then links to a full-size picture page (often referred to as a web photo album). With this thumbnail approach, a separate page is not needed for the alternate image sizes. As stated above, the browser may continue to download the larger sized images into memory while the user is viewing the first image version, which reduces the user's perceived wait time. In another embodiment, the alternate images may be stored on a server, rather than in cache memory.

A user may also customize the browser. For example, the desired resolution of alternate images can be specified according to the client computer's connection speed. If the connection speed is slow, the user may wish to sacrifice some image resolution for the sake of faster download. In addition, the user may preset the accessibility indicators of the browser, such as the default size of indicator arrows. Without this option, a user with severe visual or motor impairments may not even be able to effectively use the browser to access a larger image. By presetting the browser to automatically display larger indicator controls, this impaired user may more easily navigate a web page and access alternate images.

As a further option, the user may preset the browser to automatically display a certain image size as the default image. For example, rather than always starting from a small original image and working up in sizes, the user may wish to set the browser to display an intermediate size image.

Referring toFIG. 6, a flowchart illustrating the process of presenting alternate image resolutions is depicted in accordance with the present invention. The <IMG> HTML tag uses the source (SRC) attribute to identify the initial original image to display as the web page is first rendered (step601). If the web page contains alternate images for display, the HTML image tag has an alternate image attribute, such as ALTIMAGE, which specifies alternate image files.

The browser determines if the image has alternate images for display (step602). If there are no alternate images available, the browser simply displays the original image (step605). If the web page does contain alternate images, the browser queries the ALTIMAGE attribute of the <IMG> tag specifying the alternative image files (step603). This alternate image attribute would be similar to the ALT attribute, which provides alternate text for an image. However, the ALTIMAGE attribute can be used multiple times to allow for several alternate larger, higher resolution images. The web browser overlays a lower corner of the image with small right and left arrows (step604), and then displays the original image (step605).

If the user clicks on the right arrow (step606), the alternate larger image is accessed by the web browser and displayed on the page (step607). If the new image has another larger alternate image, the browser also displays a right arrow in its corner. In addition, the browser displays a left arrow in the corner whenever it can bring the user back to a previous alternate image or the original image. In this way, the user can choose to go on to another larger image, if available, or back to a previous image.

The design of the present invention can be implemented with the display of the arrows being a web browser view option. If the user chooses not to have the browser display the arrows in the corner of the image, the user could still cycle through the alternate images by clicking on the image itself.

The present invention can also be implemented by the use of custom plug-ins or special Java applets. However, both of these methods would require special tools, would be slower in download and web page display, and would require additional work by the web page developer to implement the web page.