PNX1500E NXP Semiconductors, PNX1500E Datasheet - Page 362

• Manufacturer Part Number: PNX1500E
• Manufacturer: NXP Semiconductors

Specifications of PNX1500E

• Lead Free Status / Rohs Status: Not Compliant

NXP Semiconductors
Volume 1 of 1
PNX15XX_PNX952X_SER_N_4
Product data sheet
Figure 3:
Undithering and Pedestal Manipulation
range for 9+1
range for 8bits
nominal data
nominal data
format
nominal data
range for 10
For true 10bits input, pedestal substraction is recommended off, the different nominal ranges for various layers
bits input
bits input
format
10 bits input
8 bits input
input
alpha (2 bit)
u/m/l (8 bit)
288~726
64~940
16~235
10bu
8bu
The UDTH unit, however, does more than just undithering. It does format conversion
as well. QVCP has its own data format protocol (10-bit signed data -- UP(Y/R), MI(U/
G), LO(V/B) --- and 8-bit unsigned alpha) and is designed to process data with a
nominal range of 9 bits; one extra bit is reserved for overshoots and undershoots.
Input data gets converted, from an external format to the native QVCP format, inside
the UDTH module.
figure, the nominal data range is shown for each conversion step for both 8- (bottom
part) and 10- (top part) bit inputs. Note that an 8-bit input to QVCP will be converted
to a 9+1 format by undithering or by left shifting. A 10-bit input, however, can be either
true 10 bits or 9+1 bits; for the former, there is not too much head-room left and so,
the nominal range of the various layers should be equalized at the VCBM unit.
The function of Alpha Processing unit is to insert a fixed alpha or pre-multiply each
pixel with a per-pixel alpha. For a 10-bit input, only fixed alpha is supported.
8bs
Unsigned to
conversion
signed
-112~107
-448~428
-224~214
Increasing nominal range by 2
8bs
10bs
could be equalized at the VCBM unit.
Rev. 4.0 — 03 December 2007
2LSB
Left shift by 1 add 0 to
increasing
Append 2nd MBS to
Nominal
8MSB
range
Figure 3
by 2
LSB position
LSB position
Undither
or
or
-224~214
10bit data from
9bs
u/m/l path and
Reconstruct
alpha path
of the MSB
shows the data-flow diagram of the UDTH unit. In the
extension
Sign
bit
-224~214
-448~428
-224~214
10bs
10bs
processing
Alpha
9bs
PNX15xx/952x Series
if pedestal substraction is on
if pedestal substraction is on
if pedestal substraction is on
removing
Pedestal
-512~364
-448~428
-256~182
-224~214
-256~182
-224~214
else
else
10bs
else
10bs
~511
-512
clip
Chapter 11: QVCP
© NXP B.V. 2007. All rights reserved.
11-362