Opened 14 years ago

Closed 10 years ago

#3911 closed defect (Won't Fix)

Downmixed multi channel AC3 audio is quieter after ffmpeg resync in [13655]

Reported by: Janne Grunau Owned by: JYA
Priority: minor Milestone: unknown
Component: MythTV - Audio Output Version: head
Severity: medium Keywords:
Cc: Ticket locked: no


The new internal AC3 decoder is 9-10dB quieter than the liba52 based one for downmixing 5.1 audio to stereo. This seems to be a issue of the downmixing code as decoding stereo AC3 is working fine.

The difference is only 4dB with ffmpeg revision 10252 from svn trunk.

Change History (6)

comment:1 Changed 14 years ago by Janne Grunau

(In [14365]) Refs #3911. Add 9dB amplification to libavcodec's ac3 downmix code.

Downmixed 5.1 is since [13655] 9-10dB quieter than the old lib52 based decoder Reprted and suggested fix by bjm

comment:2 Changed 12 years ago by Dibblah

Status: newassigned

comment:3 Changed 12 years ago by stuartm

Component: mythtvMythTV - Video Playback

comment:4 Changed 11 years ago by beirdo

Component: MythTV - Video PlaybackMythTV - Audio Output

Is this even valid anymore?

comment:5 Changed 10 years ago by Raymond Wagner

Owner: changed from Janne Grunau to JYA

This capability has been replaced by an alternate library, and we only fall through to the ffmpeg mixer if SSE is not supported by the hardware (which leaves only ARM?). It's probably safe to close this one fixed.

comment:6 Changed 10 years ago by JYA

Resolution: Won't Fix
Status: assignedclosed
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