Opened 12 days ago
Last modified 12 days ago
#10971 new defect
ffmpeg AC3/EAC3 encoder missing LFE channel in some channel layouts
| Reported by: | Jose Peirote | Owned by: | |
|---|---|---|---|
| Priority: | normal | Component: | ffmpeg |
| Version: | git-master | Keywords: | ac3 encoder |
| Cc: | Blocked By: | ||
| Blocking: | Reproduced by developer: | no | |
| Analyzed by developer: | no |
Description
ffmpeg.exe -i "5_2-2.1.ac3" -acodec ac3 -ab 384k "5_2-2.1.ac3_.ac3"
ffmpeg version n7.0-3-g607fca80b7-20240405 Copyright (c) 2000-2024 the FFmpeg developers
Input #0, ac3, from '5_2-2.1.ac3':
Stream #0:0: Audio: ac3, 48000 Hz, 5 channels (FL+FR+LFE+SL+SR), fltp, 384 kb/s
Output #0, ac3, to '5_2-2.1.ac3_.ac3':
Stream #0:0: Audio: ac3, 48000 Hz, quad(side), fltp, 384 kb/s
End job
The LFE channel is missing. The same for eac3 encode.
You can test it with the sample encoded with the old Aften.
Also the LFE is deleted in downmix when > 6 channels:
Input #0, 48000 Hz, 6.1, 6.1(back), 6.1(front), 7.1, 7.1(wide), 7.1(wide-side) or 7.1(top) always
Output #0, ac3 or eac3, 5.0
Attachments (1)
Change History (3)
comment:1 by , 12 days ago
comment:2 by , 12 days ago
Sorry my mistake, upload the correct ac3.
FL+FR+LFE+SL+SR is supported by Aften
by , 12 days ago
| Attachment: | 5_2-2.1.ac3 added |
|---|
Your 5_2-2.1.ac3 sample is not 5 channels (FL+FR+LFE+SL+SR) as your ticket suggests, but already quad(side). In fact, AC-3 does not support FL+FR+LFE+SL+SR at all.