Second Audio Track - Wrong Information

[centuryx476 8]

Hello,

I have an odd one and I do not think it is emby directly. Read to the end....

I'm encoding some movies into HEVC using Hardware Acceleration. I decided to have two audio tracks (1. Original Audio Passthru, 2. AAC Track @ 960K). When I view the data in emby the second AAC audio track is wrong. It is being reported as 320K.

So I figured maybe its the file itself. Here is the audio mediaInfo on the file.

Perhaps it is the FFmpeg commands I am using for the audio. This is the main list of commands I have come up with for encoding HEVC with two audio tracks. Mind you the titles and names of the metadata for the audio tracks can change from title to title.

I am not really sure why the second audio track is being mis-read.

 

ffmpeg -y
-vsync 0
-hwaccel cuda
-i "inputFile.mkv"

// First Audio Track (Source) Commands
-map 0:v
-map 0:a:0?
-c:a:0 copy
-metadata:s:1 title="Surround 5.1 Track"
-metadata:s:1 handler="Surround 5.1 Track"
-metadata:s:1 language=eng

// Second Audio Track (AAC) Commands
-map 0:a:0?
-c:a:1 aac
-metadata:s:2 title="AAC Track"
-metadata:s:2 handler="AAC Track"
-metadata:s:2 language=eng
-b:2 960K
-ac:2 6
-filter:2 aformat=channel_layouts=6.0

 

 

 

 

Edited May 26, 2021 by centuryx476

[rbjtech 4257]

3214 Kbps AAC track ?

I'm not surprised it's confused - that is WAY too high - it's probably defaulted to 320K.

A typical 5.1 AC3 file should result in a ~320K AAC file - not 3214K .. that is HD Audio territory (no compression) ..

[roaku 795]

16 minutes ago, rbjtech said:

3214 Kbps AAC track ?

I'm not surprised it's confused - that is WAY too high - it's probably defaulted to 320K.

A typical 5.1 AC3 file should result in a ~320K AAC file - not 3214K .. that is HD Audio territory (no compression) ..

Ya, the media info is also saying the aac conversion is the same size as the original 24 bit uncompressed source.

I don't keep ffmpeg commands in my head, but I suspect the one above isn't quite right.

[centuryx476 8]

37 minutes ago, rbjtech said:

3214 Kbps AAC track ?

I'm not surprised it's confused - that is WAY too high - it's probably defaulted to 320K.

A typical 5.1 AC3 file should result in a ~320K AAC file - not 3214K .. that is HD Audio territory (no compression) ..

In my command I am telling it to do 960K. But its not doing that

Edit: I think I figured it out. Need to verify now

Need to remove "-map 0:a:0?" from the second audio track command

 

// Second Audio Track (AAC) Commands
-map 0:a:0? - Remove this
-c:a:1 aac
-metadata:s:2 title="AAC Track"
-metadata:s:2 handler="AAC Track"
-metadata:s:2 language=eng
-b:2 960K
-ac:2 6
-filter:2 aformat=channel_layouts=6.0

Edited May 26, 2021 by centuryx476

[centuryx476 8]

So I kinda got it to work.

But I had to use MKVToolnix.

I do not know how to translate what I did there into an ffmpeg command

But in emby it defaults to 320K

Edited May 26, 2021 by centuryx476

[centuryx476 8]

I've given up on figuring out why ffmpeg is doing this. I think I am overlooking something!

Edited May 29, 2021 by centuryx476