Dear PowerArchiver users,

As PowerArchiver 2017 Beta 1 is being released today and here is an update on the
Advanced Codec Pack original article from a few months ago.

What is – Advanced Codec Pack (.pa format)?

Advanced Codec Pack combines the best available codecs and filters into one fantastic package. Most of the codecs and filters are built by us at Conexware and we also use the best open source tools where needed. PA (.pa) format has two distinctive modes – the Optimized Strong mode that focuses on superior compression strength and Optimized Fast mode that focuses on combination of great speed and good compression strength (better than ZIP in every way).

While using different modes, users may manually configure the mode that works best for them. Thanks to some unique filters and compression models, Optimized Strong mode is most likely the strongest compression mode on the market now (outside experimental archivers), and at the same time Optimized Fast mode most likely provides the best speed/strength ratio on the market as well. Together with The Advanced Codec Pack (.pa), we now fully support 64-bit systems which lets us not only increase the speed in the new .pa format (codecs and filters) but also address the maximum amount of memory available during usage.

Advanced Codec Pack (.pa) main/unique features

  • Optimized Strong mode – Optimizes codecs and filters based on selected compression level with focus on superior compression strength. It features medium to high RAM and multi-thread usage. We recommend using it with computers that have at least 4GB of RAM and 4 threads available.
  • Optimized Fast mode – Optimizes codecs and filters based on file extension with focus on fast compression and decompression speed. Up to 400-500MBs speeds in real life scenarios with normal computers (8 threads with SSD).
  • PLZMA4 (codec) – Variation of LZMA with parallel compression and decompression (multicore) for maximum speed and a unique lzmarec compression model for extra strength. This is the main codec used under Optimized Strong mode.
  • Reflate (filter) – Pre-processing filter is designed to increase compression of all deflate streams, most common ones found in PDF, DOCX, XLSX, PNG, SWF, etc. files. Translated to plain English, the pre-processing improves the compression of PDF files between 30% and 50% on average and DOCX/XLSX files up to 70% better (other archivers without special support for these files can usually compress up to 5%). The Reflate filter is used only in Optimized Strong mode due to slower speed. <click for more>
  • Deltb (filter) – A smart pre-processor for exe/dll files. It increases compression of exe/dll files by up to 10%. It is extremely fast and suitable to be used in both Optimized Strong and Optimized Fast modes.
  • x64flt (filter) – Special filter that increases compression of x64 exe/dlls by up to 10%. Extremely fast, suitable to be used in both Optimized Strong and Optimized Fast modes. Variations used: x64flt2 (slightly faster), x64flt4 (better compression).
  • FMA-REP (filter) – Deduplication filter. Due to much lower memory requirements than main codecs such as PLZMA4, the Deduplication filter can be used on a much larger window size (up to 2GB). Very fast and suitable to be used in both Optimized Strong and Optimized Fast modes. It increases compression substantially on large files.
  • ZStandard2 (Codec) – Our (parallel) version of the open source ZStandard codec used in Optimized Fast modes. It features very fast compression and decompression (up to 500MBs on real computers with SSDs) and also helps in improving the Optimized Fast mode with our filters that increase compression substantially while still maintaining excellent speed.
  • BWT/QLFC (Codec) – Fast BWT transform with QLFC compressor. Good text compression/speed ratio and is used for text/html compression as well as in combo with reflate for epub files.
  • Lepton (Codec) – Great jpeg compression codec which supports most popular jpeg format variations.
  • Ppmd_sh (Codec) – PPMd version created by our compression engineer Eugene Shelwien and is probably the best ppmd based codec available. It is used for text compression in Optimized Strong mode. Open source is available on our github.
  • Secure AES 256 bit encryption – For added security, we use the BWTS algorithm to scramble the data before AES, so attackers can not use LZ compression redundancy and other plaintext attacks to quickly check if given password is valid. This makes .pa format considerably more secure than ZIP AES. For the AES encryption module, we use FIPS 140-2 validated modules from Windows so you can rest assured that AES implementation has been tested and validated.

Big thanks to our users that have participated in the private beta testing for reporting their issues and suggestions. Since testing began, we have added a new jpeg codec and text codec. The Advanced Codec Pack (.pa) is on an accelerated development schedule and we expect to gain at least another codec before the end of beta testing, as well as to improve the current set of codecs.

PowerArchiver 2017 with Advanced Codec Pack (.PA) is now available from our download page. For more detailed information on specific features, please check other posts on our blog. We hope you will love PA 2017 as much as we do. Thank you for your support since 1998!