TM1100 Preliminary Data Book
Philips Semiconductors
13-26
PRELIMINARY INFORMATION
File: icp.fm5, modified 7/26/99
zontal direction during the move. Optional bit masking
and/or RGB overlay may be used during the move when
PCI output is specified.
13.6.10.1 Algorithms
The routine reads image data from SDRAM using the Y,
U, and V address counters, scales and filters the data in
the horizontal direction and writes it to the PCI interface
or SDRAM. The 5-tap filter scales and filters the data.
The LSB Increment value for each of the Y, U and V com-
ponents supplied by the parameter table determines the
scaling. Separate scaling factors allows YUV 4:2:2 inter-
spersed to co-sited transformation as the data is being
filtered. The scaled and filtered data is converted to RGB
or YUV format before being sent to the PCI interface or
to SDRAM. In the PCI output case, overlay data with al-
pha blending and chroma keying can be added to the
output image, and the output image can be gated by a bit
mask before it is sent to the PCI interface.
The routine reads and writes a line at a time until the full
image is transferred. The filter mirrors the ends of each
line to provide the extra pixels needed by the filter at the
ends of each line.
13.6.10.2 Parameter Table
the input and output starting addresses and offsets for Y,
U, V, OL, B and Z, the image height in lines and width in
pixels, and the scale factors for each component.
The input and output addresses are the byte addresses
of their respective tables. They need not be word or block
aligned. Note the following restriction: In packed RGB24
to PCI operation the output address offset from the start
of video memory must be a multiple of 6 bytes, i.e. on an
even pixel boundary.
The input and output line offsets define the difference in
bytes from the address of the first pixel in the first line to
the address of the first pixel in the second line for their re-
spective blocks. The line offset must be constant for all
lines in each table. The line offset allows some space be-
tween the end of one line and the start of the next line. It
also allows the ICP to scale and filter a subset of an ex-
isting image, such as magnifying a portion of an image.
There are no restrictions on line offset values other than
they must be 16-bit, two’s complement integer values.
(Note that this allows negative offsets. You can use this
to flip an image vertically.)
The input and output image height and width values are
the height in lines and width in pixels per line for their re-
spective images. The height and width are 16-bit positive
binary numbers between 0 and 64K-1.
Table 13-14. Horizontal Filter to RGB Output Parameter Table
Parameter Word
Description
Upper 2 bytes
Lower 2 bytes
Input Image Y Start Address
Y Start address of X0Y0 (byte address)
Y Counter
Start Fraction
Input Image
Y Line Offset
Starting value: may be 0.5, etc. for interspersed convert;
Y Line offset from X0Y0 to X0Y1
Y Fraction increment
Y Integer increment
Increment value for U = 1/scale factor
Y Input Image Height
Y Input Image Width
Y& Height and width in pixels
Input Image U Start Address
U Start address of X0Y0 (byte address)
U Counter
Start Fraction
Input Image
U Line Offset
Starting value: may be 0.5, etc. for interspersed convert;
U Line offset from X0Y0 to X0Y1
U Fraction increment
U Integer increment
Increment value for Y = 1/scale factor
U Input Image Height
U Input Image Width
U Height and width in pixels
Input Image V Start Address
V Start address of X0Y0 (byte address)
V Counter
Start Fraction
Input Image
V Line Offset
Starting value: may be 0.5, etc. for interspersed convert;
V Line offset from X0Y0 to X0Y1
V Fraction increment
V Integer increment
Increment value for V = 1/scale factor
V Input Image Height
V Input Image Width
V Height and width in pixels
Output Image Start Address
Start address of X0Y0 (byte address)
Control
Output Image
Line Offset
Input & output formats & control bits;
Line offset from X0Y0 to X0Y1
Output Image Height
Output Image Width
Height and width in output pixels
Bit Map Image Start Address
Start address of X0Y0 (byte address)
0
Bit Map Image
Line Offset
Line offset from X0Y0 to X0Y1
RGB Overlay Start Address
Start address of X0Y0 (byte address)