IBM39MPEGS42x
IBM39MPEGSI
MPEG S422, MPEG S420 and MPEG SI Encoders
Sseries_sds_071701.fm.02
July 17, 2001
SI Encoder Operations/Features
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For the various combinations of the above parameters, the encoded bitstream VBV size, prole and level elds are
set according to the following table.
Note: Combinations listed as INVALID will cause the encoder to either automatically adjust conicting parameters
to be consistent or hang after initialization.
The VBV buffer size may alternatively be specied by the user via command code X'0005' to Host Register X'3D'.
Picture Format
The encoder supports combinations of progressive and interlaced video formats as specied in the Table entitled:
“Input/Output Formats,” on page 17.
Input Pixel Interface
The pixel data interface will accept raster scanned digital video data up to the following:
– For NTSC, 720x512 pixels/frame at 30 frames per second
– For PAL, 720x608 pixels/frame at 25 frames per second
Data is accepted at the pixel interface at a nominal rate of 13.5MHz for a 16 bit YCbCr format, and 27 MHz for 8 bit
CCIR 656 format. The encoder will accept pixel data down to 64x64 pixels/frame. The data can be in either 4:2:0 or
4:2:2 format.
Maximum Picture Resolution
The encoder can support various picture widths, for example 720, 704, 608, 544, 352 etc. The encoder retrieves
the rst n number of pixels from each active input picture line, where n is specied by the user in Host Register
X’14’. The encoder will ignore the number of video lines specied by the user in Host Register X’1B’ and
subsequently processes the number of video lines specied by the user in Host Register X’15’.
VBV_SI Size/Prole/Level
Host Register
Parameter
Settings
MPEG-1
MPEG-2 /
≤SIF
MPEG-2 / >SIF /
≤15 Mbps
MPEG-2 / >SIF /
>15 Mbps
SP / <11-b DC
INVALID
475,136
1,835,008
9,437,184
SP / 11-b DC
INVALID
9,437,184
MP / <11-b DC
327,680
475,136
1,835,008
9,437,184
MP / 11-b DC
INVALID
9,437,184
422P / <11-b DC
INVALID
9,437,184
422P / 11-b DC
INVALID
9,437,184