PNX1700EH,557 NXP Semiconductors, PNX1700EH,557 Datasheet - Page 802

• Manufacturer Part Number: PNX1700EH,557
• Manufacturer: NXP Semiconductors

Specifications of PNX1700EH,557

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Not Compliant

Philips Semiconductors
Volume 1 of 1
5. Alpha Value and Pixel Transparency
6. RGB and YUV Values
7. Image Storage Format
PNX17XX_SER_1
Preliminary data sheet
Many of the native pixel formats include a per-pixel alpha value. This alpha value is
an inverse measure of the ‘transparency’ of a pixel. The QVCP and 2D Drawing
Engine are the only subsystems that interpret per-pixel alpha values when
compositing surfaces. The native pixel format convention of a per-pixel alpha is
shown in
Table 2: Alpha Code Value and Pixel Transparency
The QVCP input stage allows full alpha value table look-up using a 256 entry, 8-bit
wide table. This can be used to translate a non-native format alpha convention to the
native convention.
8-Bit Data
For 8-bit data, the full range of values is allowed i.e., [0~255]. As an option, the data
range could be clipped in the MBS or VIP according to the ITU-K BT. 601-4
specification.
or
10-Bit Data
For 10-bit data, the full range of values is allowed i.e., [0~1023]. The blank level is
programmable through the register.
With the exception of the planar formats, described in
image in memory is determined by the following elements:
Alpha Code
0
1
...
254
255
•
•
•
•
•
•
Y range [16~235]
U range [16~240]
V range [16~240]
R range [16~235]
G range [16~235]
B range [16~235]
Table
2.
Rev. 1 — 17 March 2006
Transparency
Fully transparent
Almost fully transparent
Almost fully opaque
Fully opaque
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
Section
Chapter 28: Pixel Formats
PNX17xx Series
3.5, the layout of an
Value
0/256
1/256
254/256
256/256
28-11