AU625684C - Electronic document display with annotation routines and multiple windows - Google Patents

Description

"Electronic Document Display With Annotation Routines and Multiple Windows'

Related Applications

The following is a related application of U.S. Patent Application Serial No. 200,091 filed on May 27, 1988 for a "Document Annotation and Manipulation in a Data Processing System and assigned to the assignee of the present invention,

Background of the Invention

In the business enviroment of today, many tasks are now automated by computers. For instance, a word processor enables the reorganizing and rewriting of documents without the retyping known in the past. In addition, various documents may be organized and stored by a computer filing system which allows retrieval by name, by chronological or alphabetical order, or by other user-desired identification. Another example is a mail system on messages to be sent to and from users of the network. Also, a phone system may be connected to a mail system which in tern enables phone messages to be stored and later forwarded to users. These and other computer devices enable various daily office tasks to be accomplished more quickly and more efficiently.

In the business environment of today, many tasks are now automated by computers. For instance, a word processor enables the reorganizing and rewriting of documents without the retyping known in the past. In addition, various documents may be organized and stored by a computer filing system which allows retrieval by name, by chronological or alphabetical order, or by other user-desired identification. Another example is a mail system on a network of computer terminals which allows messages to be sent to and from users of the network, Also, a phone system may be connected to a mail system which in tern enables phone messages to be stored and later forwarded to users. These and other computer devices enable various daily office tasks to be accomplished more quickly and more efficiently.

However, most computer devices require the user to be computer literate and to learn commands to direct the computer to perform a certain task. In more recent computer developments, menus (a series of commands from which to choose) are displayed to the user at appropriate decision junctures during the use of a computer device. The menus are considered to make the computer device more "user friendly" . Generally the choices on a menu are descriptive phrases written in terms which are more common to our everyday language rather than in a coded or technical computer language. Even so, the descriptive phrases may not initially have meaning, or at least the proper meaning, to a first-time user or a user who is not computer literate. Thus, many office personnel do not make use of computer devices because of the time and complexity required to learn to operate these devices.

Accordingly, there is a need to make computer devices, and particularly those for office use, more initially "user friendly" or readily useable especially to first-time and computer illiterate users.

Summary of the Invention

The parent application discloses a computer device which is a degree "friendlier" than the menu driven computer devices of prior art. That computer device employs an electronic stylus and an electronic tablet which emulate a pencil and desk pad of paper used by the common business person, the electronic stylus and tablet are associated with the terminal of a digital processing system which has a monitor screen for displaying the strokes input by the electronic stylus and those input by a keyboard. An audio input/output assembly is alternatively connected to the terminal to provide voiced or other audio input to the digital processing system.

User interaction with the processing sytem in that device is through movement of the stylus with respect to the tablet. During use of the stylus two major views are viewed on the monitor screen, a desk view and an annotation session view. The desk view emulates a user's desk and pieces of paper which are stacked on and moved about his desk. In a preferred emodiment the desk view shows a stamp which is a reduced or miniaturized image of an actual page of each document presently on the user system desk or computer work - area. Each stamp serves as a unique direct pictorial representation of a certain document on the user system desk as opposed to an indirect indication such as a prefabricated standard icon which is used for all documents of a certain type and which identifies as a specific document only by a name or title associated with the icon.

The annotation session view provides a full screen size view of the document to be annotated or created by data input through the stylus, keyboard and/or audio input/output assembly. The document to be annotated may be chosen in three different manners. In one way, the document may be chosen from a program being currently run by the operating system. The user simply places one end of the stylus within a predetermined proximity of the surface of the tablet. When such proximity is sensed, the currently running program is temporarily stopped, preferably by a microprocessor interrupt, the view from that program being displayed at that time becomes the document to be annotated. In preparation for annotation if the screen is currently in a text mode, as - 4 -

opposed to a bit map mode, the data processing system changes the screen to a bit map or graphics mode. Text is converted to graphics by a character generation scheme. Also the dark background with light print of the text mode is reversed to a light background with dark print to more effectively simulate print on paper. Once prepared for annotation, the document may be annotated with visual annotations input through the stylus and/or keyboard and/or annotated with audio annotations input through the audio input/output assembly.

The present invention enables a document to be chosen from a program which supports the running of multiple windows. In particular, the multiple window support program manages a database of images and enables user querying of the database for desired images. The search results from a user query of the database provides a display of an image in a dedicated image window on the monitor screen. Within that window the user is able to view, copy, print or send the image displayed therein. The program enables a mazimum number, for example 3, of image windows to be displayed on the monitor screen at one time. Typically the image windows overlap one anothe .

In accordance with the present invention, during the running of this program, if the user touches an end of the stylus to the tablet; at least one of the image windows, as displayed at that time, is captured for annotation by the annotation system. Preferably each image window displayed at the time of the touching of the stylus to the tablet is independently captured to provide independent documents to be annotated by the annotation system. In addition, the full screen view of the overlapping windows is captured and forms an annotatable document itself. Each captured image/document is represented by a stamp on the user's system desk. In the preferred embodiment the stamps of these documents are initially found in the In-box on the user's system desk.

Subsequent manipulation of the stamps and annotation of the corresponding documents is then performed as described in the parent application. In addition, the processing system - 5 -

enables a user to store documents from the use 's system desk into a desired database, for example the database of images managed by the multiple window support program. Subsequent retrieval of a desired document from a database is also enabled. This is accomplished through a file cabinet icon illustrated on the user's system desk. By the user selecting the icon with the stylus, a search routine is initiated. The search routine provides a search form in which the user specifies the desired document from a particular database to be retrieved. The search routine performs a search with the criteria inserted on the search form by the user with stylus and/or keyboard input. The search results are displayed for user selection.

Document storage is provided in a similar manner. The user positions a stamp of a desired document next to or on the file cabinet icon through operations of the stylus on a tablet. Upon positioning of the stamp on the file cabinet icon, the processing system provides a store form on the user system desk. The user completes the store form by inserting with the stylus and/or keyboard the name of the image to be stored, the desired database in which the image is to be stored, and other pertinent identification. Upon completion of the store form, the user selects a menu selection to store the indicated image in the indicated database. The processing system responds to such actions of the user by storing the specified image in the specified database and resuming display of the user's system desk with the stamp of the desired document in its initial position before it was moved adjacent to the file cabinet icon.

Brief Description of the Drawings

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of illustrative - 6 -

embodiments of the invention, as illustrated in the accompanying drawings in which like referenced characters refere to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating principles of the invention.

Figure 1 is a schematic view of a data processing system which embodies the present invention.

Figure 2 is an illustration of view displayed during the running of a multiwindow support program.

Figure 3 is an illustration of the desk view employed in the data processing system of Figure 1 in which the windows of the program in Figure 2 have been individually captured as annotatable documents.

Figure 4a-4b illustrate a sequence of views displayed from invocation of a document filing operation from the desk view in the data processing system of Figure 1.

Figures 5a-5b illustrates a sequence of views displayed from invocation of a document retrieve operation from the desk view of the data processing system of Figure 1.

Detailed Description of the Preferred Embodiment

A data processing system which embodies the present invention is illustrated in Figure 1. The system 20 includes a computer terminal 10 with a keyboard 12 and a display unit 18, a two-ended electronic stylus 14 and an electronic tablet 16, all of which are connected to and driven by a digital processor 22. Digital processor 22 may be of the multitask type but a single task type is assumed in the description of the preferred embodiment. Preferably an audio assembly 24- having input and output ports such as a telephone set, is also connected to the terminal 10 for combining voice with visual annotations input through the stylus 14 and keyboard 12.

The stylus 14 is used on an upper planar surface of the tablet 16 to perform certain tasks such as writing a message - 7 -

and correcting a part thereof, creating a new document or retrieving and annotating an existing document. The actions of the stylus 14 on the surface of the tablet 16 are displayed on the display unit 18 and the positions on the tablet have a one to one correspondence with the view 26 displayed on the display unit 18. Thus, as the user applies the stylus 14 to the tablet surface, an image representation of what the user is doing with the stylus is provided in the view 26 of display unit 18. The working elements of display unit 18, stylus 14 and tablet 16 are described in detail in the parent application and are only summarized here after as necessary. The two-ended stylus 14 operates from either end, the writing tip end 30 or the eraser end 28. The writing tip end 30 and the eraser end 28 are alternatively driven by a tablet processor. When one end is moved into and sensed in proximity (about 2 cm or less) of the tablet surface, then just that end is driven. When the writing tip end 30 is in proximity of the tablet surface it alone is driven in response to four different manners of operation to provide four different effects. A "touch and lift" operation of the writing tip end 30 or the eraser end 28 is used for selecting a displayed item. Preferably, once the stylus and 28, 30 makes contact with the tablet surface, the "touch" part of the operation is defined but the user must lift the stylus end 28, 30 from the tablet surface within the succeeding second or so to define the "lift" portion of the operation. A "touch and move" operation enables the user to move a displayed item anywhere in view 26 of display unit 18. The operation is invoked upon the user placing a stylus end 30, 28 on the tablet surface and moving the stylus end 30, 28 while maintaining it in contact with the tablet surface for more than a preset number of pixels, for example about four pixels. The third manner of operation is writing with the writing tip end 28 of the stylus 14 to insert markings on a chosen displayed document. The fourth manner of operation is erasing with the eraser end 28 to remove desired parts of markings which have been made by the writing tip end 30 within the same session of - 8 -

writing/erasing on a chosen displayed item.

Generally, the data processing system 20 provides two environments in which annotation and manipulation of documents is performed. One environment is best described as a computer work area called the user system desk which contains images of all the documents in the user's possession. The second environment provides a view of a single selected document including a new documen and enables annotation or creation of that document with stylus-written/erased, keyboard-typed and audio inputted annotations. The second environment is referred to as the "annotator" and may be invoked from any view on display unit 18 at any time. In particular, the annotator may be invoked during any working program by the user placing an end of the stylus 14 in proximity of the tablet surface. This causes the processor 22 to capture the screen view currently being displayed and generate from the captured screen view an annotation-ready document.

However, in the case where a multi-window support program is running which provides various windows 32 (Figure 2) for displaying images selected from a database of images, invocation of the annotator is not immediate but through the user's system desk. During such a multi-window support program a user is able to query the image database for desired images. In response to a query, the program performs a search in the database and provides results of the search in various windows 32 on the screen of display unit 18. Each window 32 holds an image requested by the user. In the case of more than one window 32 displayed at the same time, the program overlaps the image windows 32 as shown in Figure 2.

To invoke the annotator at this time, the user places the writing tip end 30 or eraser end 28 of the stylus 14 in proximity of the surface of tablet 16. The processor 22 responds to such positioning of the stylus 14 by causing each window 32 currently on display unit 18 to become an annotatable document represented by an associated stamp 34 on the user's system desk 36 as shown in Figure 3.

After effectively capturing each window and the composite multi-window screen view to establish annotatable documents in the above manner, the user's system desk 36 is displayed through display unit 18 as shown in Figure 3. Each document generated from the multi-window secreen view 31 (Figure 2) is represented by a corresponding stamp 34. Preferably, the stamps 34 are initially stacked in the In-box 38 in the display of the user's system desk 36. the user is able to remove each document stamp 34 from the In-box by the "touch and move" manner of operation of the stylus 14 on the tablet 16. Once the user has removed each stamp 34 from the In-box, the user may reposition the stamps as desired on the user's system desk 36 by multiple operation of the stylus 14 in the touch and move manner. Upon the user's selection of a stamp 34 by the user "touching and lifting" the stylus 14 end 28, 30 on the tablet position corresponding to the desk view position of the stamp 34, the processor 22 drives display unit 18 to exhibit a full screen size view of the document represented by the selected stamp 34, and thus invokes the annotator for the displayed document.

Subsequent annotation and returning to the user's system desk 36 or the previously running working program is as described in the parent application (i.e. through a pop-up menu) .

In addition to the various stamps 34 of documents, the user's system desk 36 (Figure 3) provides indications of various depositories for documents and various operations of processor 22 that the user can elect to perform from the user system desk. One depository as introduced above is labelled the "In-box" and is used for receiving for all documents created by the user and any mail sent to the user. The other depositories and operations indicated on the user system desk 36 and manipulation thereof are described in detail in the parent application, with the exception of a file cabinet 40.

The operation of the file cabinet 40 icon is illustrated in Figures 4a-5d. The file cabinet 40 provides a user interface for exporting an annotated document from the user system desk 36 into a desired database, for example the database of the multi-window support program, and for importing a document from a desired database onto the user system desk 36. To export or file a single document from the user's system desk 36, the user places on end of the stylus on the tablet corresponding to the position of the stamp 34 of the desired document displayed in the screen view of the user's system desk 36. After positioning the stylus in such a manner, the user maintains contact of the stylus end with the tablet and moves the stylus across the tablet to a desired position which corresponds to the screen position of the file cabinet icon 40. During such movement, the processor displays the desired document 34 stamp being moved from an initial position to a position adjacent or overlapping the file cabinet icon 40 as illustrated in Figure 4a. Upon the stamp 34 making contact with the file cabinet icon 40, the processor 22 displays a "store form" 44 in the screen view through the display unit 18 as shown in Figure 4b.

The user completes the store form 44 using the writing tip end 30 of the stylus and the keyboard 12. In the field of the store form 44 labelled "database" the user types and/or writes the name of the desired database in which the document of the selected stamp 34 is to be stored, for example, the database name of the multi-window support program. The "Image Id" field is completed by insertion of the logical identification name of the desired document. The logical identification name corresponds to a superfile identification of the desired document. The database and image id fields may be automatically completed by the processor 22 with a default database name and the logical identification name corresponding to the selected stamp 34 respectively. The user then completes the fields designated author, title and keywords by typing or writing in the respective information. The words inserted into the "key words" field are used during a subsequent search for the document in the selected database. The "File Class" field is completed by the user selecting the type of access allowed to the document. Preferable, the types of access or classes available are public, shared or private. Other user comments may be inserted in the "Comment" field.

During the completing of the store form 44, the user may erase desired stylus markings or portions thereof by operating the eraser end 28 of the stylus on the tablet positions corresponding to the desired displayed areas. To clear user inserted information from all of the fields of store form 44, the user sleets the area labelled "clear" in form 44, with the touch and lift manner of operation of one end of the stylus 14 on the tablet position corresponding to the position of the labelled area in the screen view. Upon the eraser lifting the stylus end, the processor 22 effectively erases all the information that the user inserted into the various fields of the store form 44. If the user decides not to store the document into the database the menu selection "quit" can be chosen by a touch and lift operation of the stylus 14 on the position of the tablet 16 which corresponds to the position of the pertinent menu selection in the screen view of Figure 4b. Selection of the "quit" menu pick returns the user to the desk view (Figure 3a) with the stamp 34 of the desired document in its initial position before being moved to file cabinet 40.

After completing the store form 44, user selection of the "store" menu pick causes the processor to store a copy of the document represented by the selected stamp 34 in the designated database, for example the database of the multi-window support program. The screen view of the user's system desk 36 is then redisplayed with the stamp 34 of the selected document repositioned in its initial position.

In a preferred embodiment upon selection of the "store" menu pick, the processor 22 copies the actual image data associated with the selected document stamp 34 and passes the image data and its associated parameter block to a network communication manager which in turn passes the image and parameter block to a COBOL application that stores the image data onto a magnetic or optical disk and updates two tables which support the target database (i.e. the database of the multi-window support program) . One of the tables is a locator table which provides the relationship between the physical identification on optical disk of an image to its logical identification which is supplied by the user in the "Image Id" field. The second table is the file cabinet table which relates the user designated author, keywords and logical identification to the image data for each image filed through the file cabinet icon 40. There is only one file cabinet table and it is unique to system 20 (Figure 1).

In order to retrieve an image from a database, the user selects the file cabinet icon 40 during the display of the user's system desk 36 as shown in Figure 5a. Selection of the file cabinet 40 is by the user operating an end of the stylus 14 in a touch and lift manner at the position on the tablet 16 which corresponds to the screen position of the file cabinet icon 40. Upon such touching and lifting of the stylus, the processor displays a "search form" on the user's system desk 36 through the display unit 18. As shown in Figure 5b, the search form 46 has fields similar to the "store form" 44. The "Database" field is automatically completed by the processor 22 with the name of a default database such as the database associated with the multi-window screen program. The user inserts the logical identification name or any portion thereof of the desired image in the "image id" field by writing with the stylus 14 or typing on the keyboard 12 with the keyboard cursor positioned in the "Image Id" field. The author and title of the desired document are in a similar manner user inserted in the respective fields on the search form 46. Key words to perform the search are user selected and written/typed into the proper field. The user may also insert text in the "comment" field to provide further criteria for the search. The user provided information in the comment field is used to perform a random text search in the database designated in the "database" field.

If the user makes a mistake such as misspelling a word or name in the search form 46, he may use the eraser end 28 of a stylus 14 to remove the mistake written by the writing end 30 of the stylus. Otherwise, the user may select the "clear" menu pick by a touch and lift operation of the stylus 14 on the tablet 16 position corresponding to the screen position of the menu pick. In response to this menu pick, the processor 22 clears all the user inserted information from the search form 46 and provides a "clean" search form 46.

If the user decides that a search is no longer desired, he may touch and lift an end of the stylus 14 on the tablet position corresponding to the "quit" menu selection. This causes the processor 22 to remove the "search form" 46 from the screen and display the desk view (Figure 3).

To proceed with the search after completing the search form 46, the user selects the "search" menu selection by touching and lifting an end of the stylus 14 on the corresponding tablet position. In response to selection of the "search" menu pick, the processor 22 generates a query with the user designated information on the search form 46. The query is passed to an application which processes the query on the user designated database. The application generates a result list which is transferred back through the communications network manager to the user's workstation 10 which displays the resutl list 48 on the desk view as shown in Figure 5c.

The result list 48 indicates all images in the designated database which satisfy the criteria provided by the user on the "search form" 46. The result list 48 may be more than one page long and thus may be viewed page by page with the "prev" and "next" menu picks (Figure 5c) . To make a selection of either of these menu picks, the user operates the stylus 14 in the touch and lift manner on the corresponding tablet position. In order for a user to view a listed image, the user marks an asterisk or similar indicator next to the desired listed image title with the stylus writing tip end 30 or keyboard 12 and keyboard cursor. Alternatively, the user may select all listed images by selecting the "all" menu pick by touching and lifting the stylus 14 on the tablet 16 accordingly. Thereafter, a user selection of the "retrieve" or the "review" menu selection will provide the selected images to the user in stamp or full-screen view form, respectively. Under the "review" menu selection, the processor 22 presents the selected images one by one in a full-screen view, in result list order. For each full screen view of a selected image, the user is provided with the menu selection of either "retrieve" to provide a stamp 34 of the currently displayed document in the In-box 38 on the user's system desk 36, "drop" to remove the indication of the image from the result list and present a full screen view of the next selected image, or "quit" to return to the result list screen view shown in Figure 5c. Under the "retrieve" menu selection from the result list screen view, the processor 22 provides a generation of a stamp 34 for each of the user selected images and delivers the stamps 34 to the In-box on the user's system desk 36, in result list order, until no available disk space remains in system 20. If disk space becomes unabailable, an error message is provided in the desk view as shown in Figure. 5d. The error message after being read may be permanently removed from the desk view by the user touching and lifting a stylus end on the "O.K." menu pick of the screen view as shown in Figure 5d.

With the exception of operating the stylus 14, the above is generally accomplished by know routines in the art for processing the search form 46 and manipulating the result list 48 according to user instruction. Each of the menu selections (i.e. "retrive", "review", "all", "prev", "next", "quit") are supported by associated routines to accomplish the respective function (i.e. paging, marking or screen view change, etc.). After the user is finished with the search form 46 or result list 48 screen views, the processor 22 . provides a display of the desk screen view with the stamps 34 and file cabinet 40 in the position in which the user last left them and with new stamps of any retrieved documents in the In-box 38. Thereafter, the user is able to move stamps 34 as desired by the touch and move operation of the stylus 14 and annotate documents of stamps 34 upon selection of the stamp with the touch and lift operation of an end of the stylus.

A detailed discussion of the annotating of documents from the desk view may be found in the parent application which is herein incorporated by reference.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (21)

CLAIMSWhat is claimed is

1. Annotation apparatus in a data processing system having means for annotating a displayed document, the apparatus comprising: a processor for executing programs; display means coupled to the processor for displaying views generated during execution of a program; and an annotation input device coupled to the processor for providing: a first input to stop performance of a program being currently executed by the processor, the processor in response to the first input saving an image of each window currently being displayed in a screen view on the display from the program and saving the state of the program, and a second input to annotate a saved window image through the means for annotating, the processor in response to the second input annotating the saved image and upon completion of annotating the saved image resuming execution of the program.

2. Annotation apparatus as cliamed in Claim 1 wherein the annotation input device includes a stylus.

3. Annotation apparatus as claimed in Claim 1 wherein the processor in response to the first input further saves an image of the whole screen view of windows currently being displayed from the program. - 17 -

4. Annotation apparatus as claimed in Claim 1 wherein the windows are overlapping the screen view.

5. Annotation apparatus as claimed in Claim 1 further comprising storage means for storing the saved window image in a database.

6. Annotation apparatus as claimed in Claim 5 further comprising retrieval means for retrieving images from the database including stored saved window images.

7. Annotation as claimed in Claim 6 wherein the storage means and retrieval means include a file cabinet icon-to-user interface.

8. Annotation apparatus in a data processing system having means for annotating a displayed document, the annotation apparatus comprising: a processor; an electronic display coupled to the processor; and an annotation input device coupled to the processor; and an annotation routine performed by the processor and responsive to the annotation input device to stop processor performance of a primary task, the annotation routine saving an image of each window generated by the primary task and currently being displayed on the display from performance of the primary task and saving an image of a full screen view currently being displayed on the display, the annotation routine being further responsive to the annotation input device to individually annotate the saved images through the means for annotating, and the annotation routine returning control to the primary task upon completion of annotating at least one saved image with user generated annotations input through the annotation input device.

9. Annotation appartus as claimed in Claim 8 wherein the annotation device includes a stylus.

10. Annotation apparatus as claimed in Claim 8 wherein the wondows currently being displayed as graphically overlapping windows.

11. Annotation apparatus as claimed in Claim 8 further comprising storage means for storing working documents in a database.

12. Annotation apparatus as claimed in Claim 11 further comprising retrieval means for retrieving documents from the database to form working documents which are annotatable during performance of the annotation task and for retrieving previously stored working documents.

13. Annotation apparatus as claimed in Claim 12 wherein the storage means and retrieval means include a file cabinet icon, the annotation routine responding to predefined stylus strokes performed with respect to the icon by moving user selected documents relative to the database.

14. Annotation apparatus in a data processing system having means for annotating a displayed document, the apparatus comprising: a stylus for providing input of data representing stylus strokes; an annotation routine responsive to stylus strokes, the annotation routine responding to predefined stylus strokes by stopping with an annotation task a processor performing a primary multi-window task, saving the state of the primary task and providing at least one working document from a window of the primary task, the working doucment to be annotated during the annotation task; the processor performing the annotation task, and the means for displaying documents displaying the working document and annotations made to it during the annotation task; and the processor returning to the primary task upon completion of the annotation task.

15. Annotation apparatus as claimed in Claim 14 wherein the stylus comprises: a first end for providing additive traces; and a second end for providing eraser traces, a sequence of the additive traces and eraser traces forming a sequence of input data.

16. Annotation apparatus as claimed in Claim 14 wherein the annotation routine further responds to predefined stylus strokes by providing a working document for each window currently displayed during the performance of the primary task, each working document being annotatable during the annotation task.

17. Annotation apparatus as claimed in Claim 16 further comprising storage means for storing the annotated working document in a database of the primary task.

18. Apparatus as claimed in Claim 17 further comprising retrieval means for retrieving an annotated working document from storage in the database.

19. A data processing system having means for annotating a displayed document, the system comprising: a processor for executing programs; an annotation input device coupled to the processor; a display coupled to the processor for displaying screen views generated during processor execution of a program, the screen views including multiple window views generated during processor execution of an image managing program which retrieves images from a database; and an annotation routine responsive to the annotation input device to stop execution of the image managing program during display of multiple windows on the display, the annotation routine generating for each window displayed on the display a corresponding working document annotatable by the means for annotating.

20. A data processing system as claimed in Claim 19 wherein the annotation routine stops execution of the image managing program during display of overlapping multiple windows.

21. A data processing system as claimed in Claim 19 further comprising file means for retrievably storing in the database a working document annotated with user desired annotations input to the means for annotating through the annotation input device.