Dolby Digital Plus 7.1 decoding

I am not sure whether this question has been asked before in this forum. I was checking the decoding of various audio codecs and noticed that Infuse Pro doesn’t seem to be decoding Dolby Digital Plus 7.1 track correctly. It is not detecting the dependent substreams. 7.1 track is being decoded as 6 channel LPCM.

The open source decoder in FFmpeg didn’t detect or decode the dependent substreams until the patch released last month (avcodec/eac3: add support for dependent stream · FFmpeg/FFmpeg@ae92970 · GitHub). It still doesn’t decode it correctly. I would have assumed Infuse Pro being Dolby licensed decoded it correctly. Cyberlink PowerDVD does decode it correctly on Windows.

This can tested using the Dolby Digital Plus samples linked here under HD Audio Test Clips: Samples - Official Kodi Wiki The first clip is incorrectly labeled as 5.1. It is actually a 7.1 clip.

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Thanks for the report.

At first glance, this file appears to be tagged differently than the typical 8ch E-AC3 file. For reference, I’ve attached specs for the Kodi sample as well as an E-AC3 reference file provided by Dolby.

Regardless, we’ll take a closer look to make sure we’re handling these properly.

One is encoded with the Blu-ray disc format (Kodi samples) and the other one (Dolby reference) is with the standard format. Even the one in standard format is decoded as 6 channels. Is it different with your reference clip?

Quick update.

There are a number of improvements for various E-AC3 tracks in progress for the upcoming 6.0 release. Among other things, these changes will address a few cases where 7.1 tracks are misidentified as 5.1.

Thanks for your patience. :slight_smile:

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