I found new version of AC3 filter. I has few new very interesting features
* Full DVD decoders set: MPEG Audio (layer I/II), AC3, DTS, LPCM.
* Possibility to add other decoders in future (MP3, OGG, AAC are planned and considering other formats too)
* SPDIF passthrough for MPA/AC3/DTS
* AC3 encoder for multichannel SPDIF transmission for other formats. For example if your decoder does not support DTS decode it will be possible to reencode it to AC3 on the fly and transmit it over SPDIF.
* More effective dynamic range compression instead of using AC3-embedded DRC (it is about well-known loudness problem)
ac3filter
LPCM feature is interesting. Isn't DVD-A format encrypted LPCM? If someone just could find a way to go a round that encryption.
AC3 encoding feature is also interesting if it could decode multichannel AAC some day.