Vitis Codec Library

Codec Library is an open-sourced library written in C/C++ accelerating image coding, decoding and related processing. About 6 kinds of algorithms are accelerated, including JPEG decoding, pik encoding, WebP encoding, lepton encoding JPEG-XL encoding and bicubic resizing:

• For JPEG decoding, one L2 API is provided for accelerating entire JPEG decoding process, which supports the ‘Sequential DCT-based mode’ of ISO/IEC 10918-1 standard. It can process 1 Huffman token and create up to 8 DCT coefficients within one cycle. It is also an easy-to-use decoder as it can directly parse the JPEG file header without help of software functions. In addition, L1 API is provided for Huffman decoding.
• For pik encoding, 3 L2 APIs are provided for accelerating about 90% workload of lossy compression in Google’s pik. The pikEnc used the ‘fast mode’ of pik encoder which can provide better encoding efficiency than most of other still image encoding methods.
• For WebP encoding, 2 L2 APIs are provided for accelerating about 90% workload of lossy compression in WebP which is a popular image format developed by Google and supported in Chrome, Opera and Android, that is optimized to enable faster and smaller images on the Web.
• For lepton encoding, the API ‘jpegDecLeptonEnc’ can be used for accelerating the encoding process for a new image format ‘Lepton’ developed by Dropbox. The format can save about 22% size of JPEG images losslessly.
• For JPEG-XL encoding, 3 L2 APIs are provided for accelerating the lossy encoding process of the JPEG XL Image Coding System (ISO/IEC 18181). Currently, not all computing intensive modules are offloaded, and more accelerating APIs will be available in feature.
• For bicubic resizing, the L2 APIs ‘resizeTop’ is based on bicubic algorithm, which can take 1 or 8 input samples per cycle. When taking 8 samples, it can process 80 8K images per second. Although resizing is not a coding or encoding algorithm, it is widely used with image codecs in image transcoding applications.

Library Overview

• Requirements
• License
• Trademark Notice
• Release Note
• Vitis Codec Library Tutorial

L1 User Guide

• API Document
  • namespace codec
    • hls_EncodeCoeffOrders
    • kernelParserDecoderTop

• Design Internals
  • kernelParserDecoderTop
  • Internal Design of Order Tokenize

L2 User Guide

• API Document
  • namespace codec
    • pikEncKernel1Top
    • pikEncKernel2Top
    • pikEncKernel3Top
    • kernelJpegDecoderTop
    • resizeTop
    • webp_IntraPredLoop2_NoOut_1
    • webp_2_ArithmeticCoding_1
    • jpegDecLeptonEnc
    • JxlEnc_ans_clusterHistogram
    • JxlEnc_ans_initHistogram
    • JxlEnc_lossy_enc_compute

• Design Internals
  • JPEG Decoder
  • PIK Encoder
  • Lepton Encoder
  • WebP Encoder
  • Resize Down
  • JXL Encoder

Benchmark

• Benchmark

Indices and tables

• Index
• Search Page