
1999 May 05
15
Philips Semiconductors
Product specification
STB5660 (Set-Top Box) STB concept
OM5721
Anti-flickering
The anti-flickering demonstration highlights the functions available in the SAA7215 to reduce
the line flickering in graphics regions. During this demonstration, 2 graphics regions are
displayed. One with anti-flickering and one without. The contents of the bit map in the regions
is one that shows flickering without anti-flicker measures active. Video and audio decoding are
still active and visible during the demonstration.
A picture of the running video is grabbed and displayed
1
4
of its original size as a 16-bit, bit
map on a graphics plane. The picture data of an I or P picture is copied from a frame store to
SDRAM2 memory. During the copy the format of the data is converted from 4 : 2 : 0 format to
4 : 2 : 2 and converted into the graphics memory bit map format. Then the picture is displayed
on the screen.
Grab frame store to
OSD and scale
1
4
continuously location
The demonstration runs continuously. It displays the running video while a graphics region
1
4
of the screen size is in the top left corner. This graphics region is showing the I- and P-pictures
of the running video.
This demonstration shows a 16 bit /pixel bit map in an OSD region on the screen. This picture
will be scaled to a factor
1
4
and
1
9
of the original size and displayed on the screen, after the
original is removed. The scaling is done by using a software routine that executes a DMU
program. During the demonstration, audio and video is playing.
During all the demonstrations, graphics regions with menu bars and buttons are visible for
control of the demonstration.
Scale
1
9
of 16 bit per
pixel graphics
location
Menu
Scaling
Cut-out
Display of 16 : 9 video on a 4 : 3 display by cutting out 4 : 3 centres and panning/scanning.
This demonstration shows the pan/scan control via the left/right cursor keys. This function
would usually be under control from data in the transport stream.
Display of 16 : 9 video on a 4 : 3 display using letter-boxing.
Allows a window to be selected using the cursor; the video will then be resized to fit the
selected window.
Letter-box
Continuous
horizontal, vertical
steps
Video control
Video control
Scan, freeze, play, stop
Teletext
Teletext
Switch on and off of the VBI insertion by using a graphics region in VBI lines.
Debug
Event logging
User enabled event logging provided via the RS232 debug socket.
SCREEN
FEATURE