AAC decoder problem.

[K.Y.H]

The AAC decoder cannot restore the original sound and produces a strange sound
libaac or fdk-aac is no problem.

Sample is..
​http://mail.qq.com/cgi-bin/ftnExs_download?t=exs_ftn_download&k=0c3638628ceae9c45171fb704737041757570d03520e0f0e1b0e5e07031a025a0504155a58510515040200035601045902555c556132360a185b4856610a&code=668ba768

[Balling]

Please attach the file to normal cloud storage.

[Balling]

You can use wget to download the file.

So, indeed strange. Plays well in VLC. -c copy does not fix the bug and does nothing to VLC playback, all is good.

[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] ISO: File Type Major Brand: isom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Unknown dref type 0x206c7275 size 12
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 1479, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 1323463, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 2646471, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 3969479, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 5292487, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 6615495, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 7938503, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] found tfdt time 9261511, using it for dts
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001c9e7647400] Duplicated SDTP atom

[Balling]

Sample is here: ​https://0x0.st/optc.mp4

[Carl Eugen Hoyos]

Not an obvious regression, issue disappears when remuxing to adts.

[Balling]

Replying to Carl Eugen Hoyos:

Not an obvious regression, issue disappears when remuxing to adts.

Same happens with thd files that are in containers or even sometimes without containers. They play too fast. It happens only in ffplay, not in ffmpeg though.

[Elon Musk]

Where are samples or you are spreading nonsense as usual.

[Balling]

Replying to Elon Musk:

Where are samples or you are spreading nonsense as usual.

Stop attacking me. Samples are still there (​https://trac.ffmpeg.org/ticket/9511#comment:7, but also here ​https://github.com/VoidXH/Cavern/issues/7#issuecomment-1237104265) and you still did not fix mono.THD that you broke, which I compared with EAE.exe and unless it has DRC, it was not lossless even before. BTW, DRC is supported in Plex Transcoder even for THD, and for eac3 it is much stronger that what our decoder does with drc_scale (BTW, you may want to turn it off for encoders and only default to using it when decoding to output, it may be a problem when you will finaly implement Atmos (copy some C# code from Cavern)).

[hydra3333]

"The AAC decoder cannot restore the original sound and produces a strange sound
libaac or fdk-aac is no problem."

Unless I misunderstood, which seems almost certain - are you in a position to post a sample ffmpeg commandline for decoding aac using fdk-aac library ?
Thanks

[mkver]

If you have a build with the libfdk-aac decoder, all you need to do is using -c as an input option: "-c:a libfdk_aac -i <input>". As usual, -c accepts a stream specifier.