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JPEG XR Encoder Design. Chia-Ho Pan DSPIC/GIEE NTU 10.24.2008. Outline. Introduction JPEG XR Standard Encoder Design Concept Implementation Conclusions. Introduction.
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JPEG XR Encoder Design Chia-Ho Pan DSPIC/GIEE NTU 10.24.2008
Outline • Introduction • JPEG XR Standard • Encoder Design Concept • Implementation • Conclusions
Introduction • HD Photo/WMP (Window Media Photo) has been announced by Microsoft and the JPEG (Joint Photographic Experts Group) to be under FCD consideration for a JPEG standard, titled JPEG XR. • JPEG XR is a royalty-free still image coding standard. • The goal of JPEG XR is to support the greatest possible level of image dynamic range, color precision, and keep simple device implementations.
Introduction • PSNR Comparison with JPEG and JPEG 2000 2175x2800
Introduction • High Dynamic Range
Transform • PCT (Photo Core Transform) • 2 stages in PCT module • A 16x16 MB is partitioned into 16 4x4 blocks. • 2nd stage process the DC values from 1st stage
Transform and Quantization • 3 bands after PCT transformed: DC band, low pass band (AD), and high pass band (AC)
DC Prediction • Use the LEFT and TOP block to prediction direction of current block. • The AD prediction direction follows DC prediction model.
AD/AC Prediction • The AC prediction direction is decided after the comparisons between the horizontal and vertical correlated position weighting of AD block.
Pipeline • The color conversion, pre-filter and PCT are computing with the 4x4 block style, they are arranged into the same pipeline.
Memory Reuse • Store last 2 column data for memory reusing in pre-filter, and PCT module to reduce off-chip memory access and execution time.
Implementation • Synopsys DC and PrimePower results with TSMC .18um 1P6M technology
Conclusions • The first JPEG XR chip design for HD resolution is implemented with 25 mm2 area in TSMC 0.18um CMOS 1P6M technology at 100MHz. • This powerful and advanced still image compression chip can be used for the next generation HDR display, the digital surveillance, the mobile phone, cameras of all uses, etc. • In comparing with existing JPEG2000 encoder chip, the JPEG XR has the higher PSNR performance and lower production cost (including HW area and royalty issue) benefit.