2/24/2008 9T6WP
Preliminary Hardware Data Module
BCM7405
06/29/07
Functional Description
Bro a d c o m Co rp o r a ti o n
Document
7405-1HDM00-R
Video and Graphics Display Page 1-41
-
W_RGB_1_565
•
16-bit formats
-
RGB_565
-
WRGB_1555
-
RGBW_5551
-
ARGB_4444
-
RGBA_4444
-
AP_88
•
8-bit format
-
A_8
-
P_8
•
Other formats
-
P_4
-
P_2
-
P_1
-
P_0
-
A_4
-
A_2
-
A_1
A horizontal scaler is either inside the graphics feeder or just downstream from it. This scaler can only handle horizontal
upscaling, and has an 8-tap filter for this up-scaling function.
Video Scaler
The video scaler is SD and HD capable and is designed to include the following features:
•
Picture size: Up to 1920 pixels per line and 1080 lines per picture (both input and output).
•
Pixel format: Both input format and output format are 4:2:2 YCrCb with 8-bits per component.
•
Scaling capability: Independent horizontal and vertical scale factors. Both of them are ranged from 1/32 (downscaling)
to 32 (upscaling).
•
Sampling position: Sampling position is maintained internally using two M mod N counters (one horizontal and one
vertical). It is rounded to the nearest 1/256 pixel in both directions. In addition, sampling position can be initialized by a
subpixel amount.
•
Mode of operation: Four modes of vertical FIR and/or block averaging can be selected.
•
Two optional horizontal halfband decimation filters can be enabled for cascaded operation in high-quality decimation.
•
Horizontal non-linear scaling allows projection of 4:3 material onto 16:9 screen.
Motion Adaptive De-interlacer
The motion adaptive de-interlacer block is responsible for converting the an interlaced format into a progressive format. This
improves the visual quality for progressive displays.
•
Accepts up to 720x480i and produces 720x480p in the case of NTSC.
•
For PAL, up to 720x576i is accepted producing 720x576p.
•
Motion adaptive algorithm smoothly blends various approximations for the missing pixels to prevent visible contours
produced by changing decisions.
•
Automatic 3:2 pull-down cadence detection.
•
Reverse 3:2 pull-down for improved quality from film based sources.