
8-18
Video Decoder Module
8.2.11 User Data
User data is written to the User Data FIFO, which is separate from the
Auxiliary Data FIFO. The Group of Pictures (GOP) User Data Only bit in
Register 239 (
page 4-55
) controls the user data processing. When this
bit is cleared, user data of all layers is written to the User Data FIFO as
shown in
Table 8.11
. When this bit is set for each sequence, only the first
GOP-layer user data is put into the User FIFO. User data belonging to
others layers is discarded. See also
Section 8.2.15, “User Data FIFO
Operation.”
8.2.12 Picture Data
All layers of syntax including and below picture data, i.e., slice, macro-
block, and block are processed by the decoder to reconstruct the picture.
None of the parameters in picture data are written to the Auxiliary Data
FIFO or the User Data FIFO.
8.2.13 Unsupported Syntax
The decoder supports Main Profile @ Main Level. As such, there is no
support for scalable extensions, i.e., sequence scalable extension,
picture temporal scalable extension, and picture spatial scalable
extension. Chroma formats 4:4:4 and 4:2:2 also are not supported.
Table 8.11
All User Data Processing
Parameter
P
N
32
B
bslbf
A
1
1. bslbf = bit stream left bit first; uimsbf = unsigned integer, most significant bit first
W
U
n
U
D
n
B
B
B
B
B
B
B
B
user_data_start_code
(PscB2)
while (nextbits() ! = ‘0000
0000 0000 0000 0000 0001’)
user_data
A[7:0] 8 * n uimsbf
y
n
A7 A6 A5 A4 A3 A2 A1 A0