PXD20RM Datasheet, PDF (456/1628 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

Line 1
SAV
EAV
80
Frame of image data
9D
Line 480
SAV
Frame blanking period
EAV
AB
B6
NOTE: The SAV and EAV bytes are included as part of the blanking period.
Figure 11-97. Relationship Between Hblank and Vblank in Internal Sync
11.8.1.6.3 PDI YCbCr mode and DCU3 YCbCr color format
The DCU3 can process incoming data from the PDI and from memory in YCbCr422 format. Both sources
use the same RGB conversion and interpolation equations, however, the coefficients for the equations and
enable for the interpolation are independently controlled.
In YCbCr mode, the PDI extracts the ITU656 sync (FF-00-00) and sends the video to the processing
functions. The first processing function converts the 422 stream to a 444 stream, by providing interpolation
on the chroma components of the stream depending on PDI_INTERPOL_EN bit. The second processing
function converts the stream to RGB888/RGB565.
The DCU3 can also select YCbCr format in the BPP field of layer descriptor 4, which allows the same
process to be applied to values stored in memory rather than brought in from the PDI. Interpolation is
controlled for the layers using the LYR_INTPOL_EN register.
The RGB pixel value is computed using following equations:
Red
=
_---Y_------–_----1_---6_----_---_---y_----r_--e_---d_-
512
+
_---C_----r_----–_----1_---2_---8_----_--C_----r_---r_--e_---d_--
512
+
-^--^C----^b-----^–----¹---²---⁸----^--^C----^b----^r--^e---^d--
512
Eqn. 11-7
Green = ^---^Y------^–----¹---⁶----^---^---^Y-----^g---^r---^e---^e---ⁿ- + ^---^C----^r----^–----¹---²---⁸----^--^C----^r---^g---^r---^e---^e---ⁿ- + -^--^C----^b-----^–----¹---²---⁸----^--^C----^b----^g---^r---^e---^e---ⁿ-
512
512
512
Eqn. 11-8
Blue
=
_---Y_------–_----1_---6_----_---_---y_----b_---l_--u_---e_-
512
+
_---C_----r_----–_----1_---2_---8_----_--C_----r_---b_---l_--u_----e_-
512
+
_---C_----b_-----–_----1_---2_---8_----_--C_----b_----b_---l_--u_----e_-
512
Eqn. 11-9
Note that the first multiplication (i.e (y-16)*ycoeff) is unsigned, the two others are signed.
11-122
PXD20 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor