Broadcom BCM7405 - Motion Adaptive De-Interlacer; Video Scaler

2/24/2008 9T6WP
Preliminary Hardware Data Module BCM7405
06/29/07 Functional Description
Broadcom Corporation
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.