IPS-VIDEO Altera, IPS-VIDEO Datasheet - Page 142

• Manufacturer Part Number: IPS-VIDEO
• Description: MegaCore Suite W/ 17 DSP Video/image Processing Functions
• Manufacturer: Altera
• Type: -r

Specifications of IPS-VIDEO

• Software Application: IP CORE, SUITES
• Supported Families: Arria GX, Cyclone II, HardCopy II, Stratix II
• Core Architecture: FPGA
• Core Sub-architecture: Arria, Cyclone, Stratix
• Rohs Compliant: NA
• Function: Suite of IP Functions for Video and Image Processing
• License: Initial License
• Lead Free Status / RoHS Status: na
• Lead Free Status / RoHS Status: na

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Video and Image Processing Suite User Guide
Polyphase and Bicubic Algorithms
The sum is then weighted proportionally to these errors. Note that because the values
are measured from the top-left pixel, the weights for this pixel are one minus the error.
That is, in fixed-point precision:
The sum is then:
The polyphase and bicubic algorithms offer the best image quality, but use more
resources than the other modes of the scaler. They allow up scaling to be performed in
such a way as to preserve sharp edges, but without losing the smooth interpolation
effect on graduated areas.
For down scaling, a long polyphase filter can reduce aliasing effects.
The bicubic and polyphase algorithms use different mathematics to derive their filter
coefficients, but the implementation of the bicubic algorithm is just the polyphase
algorithm with four vertical and four horizontal taps. In the following discussion, all
comments relating to the polyphase algorithm are applicable to the bicubic algorithm
assuming 4×4 taps.
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Chapter 5: Functional Descriptions
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May 2011 Altera Corporation
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