FIELD OF INVENTION
The present invention relates to a method for applying an effect at the time of
channel transition or switching of channels.
BACKGROUND OF THE INVENTION
Generally when user presses a button to switch a channel a black screen (or
video mute) occurs and then next / target channel appears. This "video mute"
situation at the time of switching a channel irritates the user. During this channel
transition period other information or data (or "zap page") can be displayed to a
viewer.
US Patent 7, 237, 251 provides a "zap page" which may include advertising,
information on the next program, a window of a segment of the next program
transmitted over the target channel, information concerning the viewer like
notification of arrival of an e-mail, stock prices of securities in the viewers
portfolio etc, and information about viewers point of interest, and / or local

information. The "zap page" may also include interacted elements pre-rendered
and stored within the digital set top box (STB). The "zap page" is displayed till
the channel switch is completed. If the viewers engage in an interactive session,
the display of the next channel is suspended till the interactive session
dissengages. This is a definitive disadvantage with the prior art method.
SUMMARY OF THE INVENTION
The main object of the present invention is to provide an effect on the existing
channel, whenever the channel-change key is pressed for effecting a change in
the channel. Whenever user presses a key to switch a channel, existing channel
that is being viewed, will show an effect, which can be with / without sound, and
then the display is switched to the next target channel. For example, when a
viewer is watching a particular channel and a key to switch the channel is
pressed, the system will freeze the display first and apply the effect on the
existing display and when the channel-switch is completed, the next target
channel will be displayed.

Thus the present invention provides a method for applying an effect at the time
of channel transition, comprising the steps of: pressing a key for switching a
channel; freezing existing content in display unit; applying special effects on the
display unit after freezing of the existing display; performing channel switching
task; and displaying the next target channel in the display unit.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention can now be described in detail with the help of the figures of the
accompanying drawings in which
Figure 1 shows in block diagram form operation of a generic television
based on the present invention.
Figure 2 is a diagrammatic representation of the
process of the present invention.

Figure 3 is a flow chart for the execution of the present invention.
Figures 4(a),
4(b),4 (c) show example of the invention or
the actual view of the end user at the time of channel switching.
DETAILED DESCRIPTION
As shown in Figure 1 a television remote control 1 is used for transmitting
infrared commands to the infrared receiver of the television receiver circuit 2 for
providing infrared data (PWM waves) to a micro-controller 3. The micro-
controller 3 is used for decoding of IR data, processing the data, invoking of an
appropriate application, and generation of on screen display (OSD) with
appropriate font and colour. The process data can be stored in an EEPROM 4.
The storing and fetching data can be performed with the help of any IIC. The
picture and the OSD are displayed on the display unit 5.

As shown in Figure 2 the process of the present invention involves pressing a key
for switching a channel. The next step is freezing the existing content at the
display unit. The special effects are then applied on the display unit after
freezing of the existing display. The channel switch task is then performed.
Finally the next target channel is displayed in the display unit.
The flow chart for the execution of the present invention is shown
diagrammatically in Figure 3, which is self-explanatory.
Figure 4 shown an example of the display the user observes at the time of
channel switching of the present invention.
Figure 4(a) shows a news channel being watched by a viewer, when the viewer
decides to change the channel. When the user presses a key to switch a
channel, the content of the existing channel that is being viewed is frozen in
stages 1, 2, 3 and 4 as shown in Figure 4(b).

The effect is then applied on the frozen content and the next target channel
program is displayed. The target channel then appears as shown in Figure 4 (c).
For changing the channel the user can press either a sequential channel
navigator, for e.g. the up-down key for channel change, or directly through the
channel number keys. The channel which is being viewed would show an effect
with / without sound and then display the next target channel. This feature of
the present invention work both in reverse and in forward direction, i.e. from
channel 1 to n or from channel n to channel 1.
Thus the present invention hides the "video mute" situation during switching of a
channel and displays some other visual effects of interest to the viewer. The
television memory may contain a list of supportive type of effects that can be
applied at the time of channel switching. The execution of effect/ effects can be
controlled by the user and the effects can be applied in any manner selected by
the user like, random or constant. The effects can also be applied with / without
sound, thus making channel switching task more effective.

WE CLAIM
1. A method for applying an effect at the time of channel transition,
comprising the steps of:
- pressing a key for switching a channel; freezing existing content in
display unit;
- applying special effects on the display unit after freezing of the
existing display;
- performing channel switching task; and
- displaying the next target channel in the display unit.
2. The method as claimed in claim 1, wherein channel switching can be
performed by pressing either a sequential channel navigator, like an up-
down key, or directly through channel-number keys.

3. The method as claimed in claim 1, wherein the television set may content
in its memory a list of supportive types of effects that can be applied
while switching channels.
4. The method as claimed in the preceding claims, wherein the visual effects
can be applied in any manner selected by the user, with / without sound,
thus making the channel making task more effective.
5. The method as claimed in the preceding claims, wherein the channel
switching can be performed in both forward and reverse direction, that is
from channel 1 to channel n or from channel n to channel 1.
6. A method for applying an effect at the time of channel transition,
substantially as herein described and illustrated in the figures of the
accompanying drawings.

The main object of the present invention is to provide an effect on the existing
channel, whenever the channel-change key is pressed for effecting a change in
the channel. Whenever user presses a key to switch a channel, existing channel
that is being viewed, will show an effect, which can be with / without sound, and
then the display is switched to the next target channel. For example, when a
viewer is watching a particular channel and a key to switch the channel is
pressed, the system will freeze the display first and apply the effect on the
existing display and when the channel-switch is completed, the next target
channel will be displayed.