SIMD Implementation of Discrete Wavelet TransformOutlineMotivationGoal2D Discrete Wavelet TransformDWT SchemesDWT Schemes (continued)JPEG Codec Analysis using JasPerApproachConclusionReferencesSIMD Implementation of Discrete Wavelet TransformJake AdriaensDiana PalsetiaOutlineMotivationGoal2D Discrete Wavelet TransformDaubechiesLiftingApproachConclusionMotivationIncreasing focus on multimedia has lead new image coding called JPEG-2000JPEG-2000 over JPEGAchieves higher compression rate Computationally more intensiveReplaces low-complexity and memory efficient block DCT with Discrete Wavelet TransformGoalImprove computation of DWT TransformLowering memory access Align memoryApply loop transformation techniquesExtracting ParallelismCompute independent data in parallel2D Discrete Wavelet TransformSubband Decomposition of 1-D signal2-D DWT 1-D DWT on each row followed by 1-D DWT on each columnDWT SchemesDaubechieswavelet function is passed x samples to calculate wavelet coefficientrequire a temporary array hence not memory efficientDWT Schemes (continued)Lifting Schemememory efficient compared to Daubechies Use correlation in data to remove the redundancyOriginal 1-D sequence is split in even and odd indexed sequenceValues are iteratively modified by predict and update steps: update stepd: predict stepP: predict weightsU: update weightsJPEG Codec Analysis using JasPerTable 1: RunTime using GNU profiler for 1792x1200 bitmap imageApproachInitial: modify JPEG-2000 to incorporate SIMD implementation using SSE2Current:Implement C based DWT algorithm (Daubechies 4 and Daubechies 4 with lifting)Take the original algorithm and apply subword parallel functions using SSE2 instruction set Compare Speedup of original algorithm with SSE2 implementationConclusionDWT Superior to DCT (multi-resolution analysis)Computationally complexImplement Wavelet Transform Schemes Use SIMD instruction for optimization Compare PerformanceReferencesDaubechies D4 Wavelet Transform http://www.bearcave.com/software/java/wavelets/daubechies/index.htmlM. Rabbani, and R. Joshi, “An overview of JPEG 2000 still image compression standard”, Signal Processing: Image Communication, vol. 17, pp3-48, 2002A. Shabahrami, B. Juurlink, S. Vassiliads, “Performance Comparison of SIMD Implementations of Discrete Wavelet
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