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Description  |
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BACKGROUND OF THE INVENTION
Technical Field
The present invention relates to information processing of computer
networks, more specifically, to a method for indicting the location of
video hot links.
Prior Art
Hypermedia is a term used to describe the fusion of two other new
technologies: multimedia and hypertext. Multimedia refers to information
forms containing text, image, graphics, audio and video. A hypertext
document is one which is linked to other documents via hyperlinks. A
hyperlink often appears in a hypertext document as a piece of highlighted
text. The text is usually a word or phrase describing something of which a
user might want further information. When the user activates the
hyperlink, typically by clicking on it using a mouse, the user view is
changed so as to show the linked document, which typically contains more
information on the highlighted word or phrase concerned. Hyperlinks make
it easy to follow cross-references between documents. Hypermedia documents
are hypertext documents with multimedia capabilities. The regions on the
screen which are active hyperlinks are called hot-links.
Nowadays, most people are familiar with the application of hypertext by
using a mouse to click on hot-links on computer displays of homepages from
the World Wide Web (the Web) on the Internet. Data on the Web is located
via URLs. URL stands for Uniform Resource Locator. It is a draft standard
for specifying an object on the Internet. It specifies access method and
the location for the files. Documents on the Web are written in a simple
markup language called HTML, which stands for Hypertext Markup Language.
File formats of data on the Web are specified as MIME formats; MIME stands
for "Multipurpose Internet Mail Extensions". (Reference:
http://www.oac.uci.edu/indiv/ehood/MIME/MIME.html). Examples of File
formats on the Web are .au (probably the most common audio format), .html
(HTML files), .jpg (JPEG encoded images), .mid (Midi music format), .mpg
(MPEG encoded video), and .ps (postscript files).
While presently hypertext technology is most common in text and image
media, it is beginning to also appear in animation and video. HyperVideo
is the name for video augmented with hyperlinks. NEC corporation has
demonstrated to Newsbytes such a system, named video hypermedia system,
that will bring the point and click capabilities of hypertext to full
motion video (NEC's Video Hypertext System, Newsbytes News Network, Jul.
31, 1995.).
HyperCafe is an experimental hypermedia prototype, developed as an
illustration of a general hypervideo system (Nitin "Nick" Sawhney, David
Balcom and Ian Smith, HyperCafe: Narrative and Aesthetic Properties of
Hypervideo, Hypertext 96: Seventh ACM Conference on Hypertext (Recipient
of the first Engelbart Best Paper Award at Hypertext 96, Mar. 20, 1996),
http://silver. skiles. gatech. edu/gallery/hyper cafe/HT96_Talk/). This
program places the user in a virtual cafe, composed primarily of digital
video clips of actors involved in fictional conversations in the cafe.
Hypercafe allows the user to follow different conversations, and offers
dynamic opportunities of interaction via temporal, spatio-temporal and
textual links to present alternative narratives.
VideoActive is an authoring tool for the creation of interactive movies
(HyperVideo Authoring Tool (User Notes), http://ephyx.com/, Pre-Release
version, Feb. 1996). It uses the HyperVideo technology to include
hot-links in digital video files. The tool allows one to prepare video
clips with the hot-link information and then to link them with other types
of media.
Hot links in hypertext files are highlighted presently by way of color
variation. When normal hypertexts are black, for instance, the hypertexts
containing hot links are of another color (e.g. blue). In this way, the
users can learn whether there exists a hot link in the hypertexts through
changes of the colors. However, color is an important information in other
hypermedia (image and video) files, hence the user might get a distorted
image and video if the same method as mentioned above were still used to
indicate whether there exist hot links in the image and video files. In
case that there is a red flower in a certain frame of a video, for
instance, the information contained in the video itself will evidently
distorted if the hot link on the red flower is indicated directly by way
of color variation. Therefore, it is undesirable to directly adopt the
method of color variation in hypermedia (such as video) files. In the
current hypervideo demo systems, the mouse cursor is often moved into a
video display window and is moved around continuously within the window to
find out whether there exist hot links in the video. For instance, when
the cursor shape changes, it shows that there is a hot link. The method
for seeking hot links contained in the video by way of mouse cursor's
roaming within the video window is very inconvenient.
The objective of the invention is to provide a method for indicating the
location of time dependent video hot links to a user, including the method
for indicating the presence and the location of a hot link.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a method for indicating the
location of time dependent video hot links to a user, comprising the steps
of: displaying a motion video presentation on a first portion of a display
device, the device presentation including a hot link region which can be
selected by a user to link to different content; displaying an indication
of the presence of the hot link region in the video presentation.
The method of the invention may comprise the further step of altering a
visual attribute of at least a portion of the hot link region when a user
manipulable cursor is within the first portion.
The method of the invention may comprise the further step of displaying an
indication of the presence of the hot link region in the video
presentation on a second portion of the display screen.
With the method of the present invention, it is possible to indicate the
presence and location of a hot link without mouse cursor roaming or
intrusion of the active video window. That is to say, a user can view in a
non-intrusive mode while he can get the information about the presence and
the corresponding location (if present) of a hot link.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be described by
vary of example only, with reference to the accompanying drawings, in
which:
FIG. 1 shows schematically a first embodiment of the present invention.
FIG. 2 shows schematically a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
FIG. 1 shows schematically a first embodiment of the invention. In this
embodiment, video is being displayed on a computer monitor 1000. This
monitor displays data (text, video) which is generated by a computer 1001,
to which are also attached a keyboard 1002 and a mouse 1003 in standard
configuration. Speakers are attached to the computer. The video is
accompanied by audio, as is typical in motion pictures. The computer is
also connected in standard fashion to a network connecting device 1004
such as ethernet, token ring or telephone modem, which allows access to
the World Wide Web.
The video is contained inside a video display window 1010. The window is
bordered in standard fashion, to allow for moving it or resizing it by
utilizing the mouse in standard fashion. The top border is a standard
panel bar 1020 with an active file button 1021 which, when activated by
pointing the cursor at it and clicking with the mouse, displays a menu for
initiating actions such as exiting the video program; an active button
1022 which, when activated, displays an options menu; and active buttons
1023 for miniaturizing the display window to an icon on the screen or on a
control bar (as in Windows 95), for fast resizing between normal size to
full screen size, and for fast termination of the video program. Such
button configurations are standard. Underneath the window is a panel bar
1030 which contains active regions (buttons) 1040 for controlling typical
video functions as play and stop/pause, and an active slider 1050 For
controlling random access to temporal locations in the video. Such
configurations are standard in the art.
The displayed video has been encoded with embedded hyperlinks. These are
certain regions 1080 within the video display window for which at certain
time intervals special information has been encoded in the video data
stream that point to html files in various URLs which are connected to the
computer network. Such region 1080 during such time period is called a
hot-link.
On the panel bar 1030 is an active light region 1060. During those time
periods in which there are no hot-links encoded in the video, the light
region is green. During those time periods in which there are hot-links in
the video, the light region is red. If the cursor is inside the display
window while there is a hot-link in the video, that region is highlighted
by either a color change or an easily observed border; the option is
offered in the options menu.
If a user clicks the left button of the mouse while the cursor 1070 is
inside the hot-link, a signal is transmitted from the computer to the
encoded URL requesting the delivery of the linked html file back to the
computer. The contents of the html file contain instructions which the
computer executes. Typically these will be to display text or multimedia
data on the monitor; the multimedia data may also include audio played out
of the speakers. While this new data is being displayed, the video is
paused. This is achieved either by a pause command on the video player if
the video data has already been downloaded to a local file, or (more
typically) by transmitting a pause request to the URL from which the hot
video is being streamed, and having that location issue a pause command to
stop the streaming. If the originating URL does not support a pause
command, then the video continues. The user has an option to miniaturize
the video display window while he is viewing the newly displayed
information. At some later time, the user may resume the hot video by
pointing to the play button in 1040 with the cursor and clicking a button
on the mouse.
If the viewer chooses to view the video in full screen mode (which he can
do by clicking the resize button in 1023), then the active light region is
embedded in the video display window (now the entire display window) at
the bottom right corner.
At any time period, more than one hot-link may be present in the video, and
they are simultaneously visible if the cursor is inside the video display
window.
A second embodiment of the invention is schematically shown in FIG. 2. The
configuration is similar to that of FIG. 1, with objects (2xxx) of FIG. 2
corresponding to objects (1xxx) of FIG. 1. An object corresponding to 1060
of FIG. 1 is not present in FIG. 2. Objects 2009 and 2100 of FIG. 2 have
no corresponding objects in FIG. 1 Object 2009 is a horizontal indicator
bar and object 2100 is a vertical indicator bar. When a hot-link is
present in the displayed video, the X-coordinate of the center of the
hot-link is indicated on the horizontal indicator bar directly below it by
a bright dot, and the Y-coordinate of the center of the hot-link is
indicated on the vertical indicator bar directly to its right by a bright
dot. As in the previous embodiment, if the cursor is inside the display
window while there is a hot-link in the video, that region is highlighted
by either a color change or an easily observed border; the option is
offered in the options menu. The user accesses the html file corresponding
to the hot region in the same manner as in the first embodiment.
Since the indicators of the second embodiment pinpoint the center of the
hot-link, there is an option also accessible via the option menu for
eliminating the hot-link highlighters inside the video display window. The
user can still quickly move the cursor to the appropriate X-Y coordinate
position within the video display window and click on the hot-link. Since
hot regions typically correspond to recognizable image segments, such as
people, faces, animals, objects, the user need not position the cursor
exactly at the X-Y coordinates to be within the hot-link region. Another
option within the options menu is that the cursor itself is changed when
it is inside the hot-link. This may be a color change or an addition of a
question mark next to the typical cursor, or other change.
Another option accessible via the options menu is that the horizontal and
vertical indicator bars exhibit via lighted horizontal and vertical line
segments the corresponding support intervals of hot-link. Thus, if the
hot-link is a rectangle, then the horizontal bar is lighted along the
entire interval directly below the hot-link, and the vertical bar is
lighted along the entire interval directly to the right of the hot region.
If the hot-link is an ellipse, the lighted intervals on the indicator bars
may correspond to either the largest rectangle whose sides are parallel to
the indicator bars and which lies either completely inside the ellipse of
the smallest rectangle whose sides are parallel to the indicator bars and
which contains completely the ellipse. Multiple hot-links in a single
frame may have regions whose x-coordinates or y-coordinates overlap.
Various options for user interfaces to convey this information on the
indicator bars are envisioned, and follow directly from the invention
herein.
It will be observed that the invention provides the user the ability to
view a hot video without intrusion of hot-link indications inside the
video window as well as the ability to view the video with indicators
inside the video window visible. The choice can be dynamically invoked by
simply moving the cursor out of or into the video display window. When the
user is viewing in a non-intrusive mode, the light indicator provides
information as to the presence of a hot region, alerting the viewer that
if he so chooses, he can quickly determine the location of the hot-link by
moving the cursor inside the display window.
Creation of hot video content is achieved in the following way. An MPEG
encoded video source is used for this particular embodiment (D. LeGall,
MOEG: A Video Compression Standard For Multimedia Applications,
Communications of the ACM, Vol. 34, No. 4, April 1994). The MPEG system
layer contains packets of video, audio, and user specified date
(International Organization For Standardation, ISO/IEC JICI/SC291/WG1,
Coding of Motion Pictures and Associated Audio, NO272, Jun. 10, 1994). The
user specified data will contain the hot-link information. Hot-link
information for a given frame in the video will be encoded in a packet
which immediately precedes the packet which contains the beginning of the
video data for that frame. A hot video editing system comprising an MPEG
playback system is used. It can play back the MPEG video in real-time
mode, slow mode, or single-frame-at-a-time mode. It also has editing tools
for inserting the hot link information. At any desired frame, the user
freezes the playback at that frame. Using the editing tools, the user
indicates the desired region which is to be hot. After the region is
indicated, the user labels the region with a pointer to a URL. A list of
URLs for the particular video sequence is maintained, and displayed along
the frozen single frame. If the desired URL is already in the list, the
user simply has to click on it with a mouse to achieve the labeling. If
this URL is new, the user has to enter it into the list and then point the
hot-link to it. The editing system inserts this information into the user
data packet, as discussed above.
An alternate embodiment for the creation of hot MPEG video, which is
extensible to other video formats, is the following. A hot video editing
system is used, as above. This time, instead of embedding the hot-link
information into the MPEG system layer data stream, a new type of data
stream is created, which mixes the MPEG system layer with the hot-link
information. This will form a new MIME type, consisting of a sequence of
hot video information for a particular frame, followed by the video data
of that particular frame. Special start code symbols are used to indicate
the start of a hot video data segment; and other special start code
symbols are used to indicate the start of a MPEG video data segment.
Both hot video creation systems described above can be automated for faster
creation of hot video. For example, motion estimation techniques as in
MPEG encoding may be used to predict location of a hot-link in a frame
from a previous frame. The interactive editing system allows the user to
view the automatically created hot-link regions, and the user can make
modifications if necessary.
A hot video decoder is utilized by a browser whenever it identifies the
incoming data as hot video data; this identification is via the suffix of
the data name. If the data is encoded using the first embodiment, with
hot-link information embedded in the MPEG data stream, then the hot video
decoder is an MPEG decoder which also understands the data provided by the
user-specified data packets. The decoder determines start of video, audio
or hot-link info from the packet start codes. It then utilizes these three
sets of information, the hot video data to determine the active regions
and the URLs to which they point, and the MPEG video and audio data to
synchronize and display the audio and video. If the data is encoded using
the second embodiment, the decoder determines start of video or hot-link
info data from the start code headers. It then utilizes the two sets of
information, the hot video data to determine the active regions and the
URLs to which they point, and the MPEG audio/video data to playback the
video.
A hot video decoder is created as follows. Using Microsoft's Visual Basic,
one creates a main form which looks like the one in FIG. 1. It contains a
video window, plus buttons, a slider, and a color indicator. The default
color of the color indicator is green. The decoder utilizes an MPEG
decoder which decodes data coming either from file or streaming data. The
decoder also interprets user packet data, which contains the information
regarding time and place of hot link regions in the video. The decoder
sets up an array for hot-link region information. The array contains the
coordinates of the hot link regions. The decoder also sets up a hot-link
flag; if there is no hot-link region, the flag is set to 0; if there is a
hot link region then the flag is set to 1. The decoder polls the flag
every 33 milliseconds. If the flag is 1, indicating the presence of a hot
link region, the color indicator turns red. The decoder then checks the
hot link region to determine the position of the hot link region. It also
checks the position of the cursor. If the cursor is inside the video
window, then a border is displayed around the hot link regions. If
furthermore the cursor is inside the hot link region, then the cursor
shape is changed. If a user clicks the mouse while the cursor is inside a
hot link indicator, then the linked page is displayed on the computer
monitor, and the video is paused. If the hot link flag is 0, and if the
color indicator was red, it now turns green; if there existed hot link
regions, then all hot link region borders are removed; and if there was a
special shaped cursor inside a hot link region, then the cursor resumes
its default shape. Otherwise, the color indicator remains green, and the
video proceeds undisturbed. The means of achieving the above described
process are standard in the art.
While the invention has been particularly shown and described with respect
to preferred embodiments thereof, it will be understood by those skilled
in the art that the foregoing and other changes in form and details may be
made therein without departing from the spirit and scope of the invention.
* * * * *
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Description  |
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