m4b metadata loss with Convert format...

[Deranged Hermit]

Hi,

First post. I'm using Windows MediaMonkey Gold v6.x 2024.0.0.3082. I'm converting audiobook m4b files to m4b files with smaller file sizes. Input files are stereo, either 22k or 44k samples/sec, and I'm converting to mono and 11k, using the MM Codec Pack 3.08 (Trial). I bought the MM Codec Pack (3.09), but after three or four reinstalls, have not been able to get that one to work at all.

The re-encoding has reduced the size of my audiobook database from ~450Gb to ~200Gb. That took about a week. I started with the free MM, and got the paid version when I saw it will use multiple processors for format conversion. That worked very nicely, and the background batch function worked well. Looking at Windows Resource Manager, I could see that one batch job of 50-100 books would keep the 12 processors loaded to around 40%-60%. But starting another batch job of similar size boosted processor use up to around 90%, so I could kick off two jobs before bed and let them run overnight.

Unfortunately, it seems some metadata has been lost as part of the process. Specifically, the chapter info seems to not be transferred. I also notice the book summary is gone, so other metadata may also be lost. I see no options in the "Convert format..." dialog to include / remove various metadata.

I hope MediaMonkey Android can use the chapter metadata once it is there. I will try it with some audiobooks with known chapter data to see what it does. I like the MMA user interface better than Listen or Smart ABP.

Maybe I am doing something wrong. Any help appreciated.

[Lowlander]

Can you please provide an original M4B file to Support?

[Peke]

Hi,
Can you also if possible also same file but Converted M4B file to compare your and our results?

[MiPi]

Hello,
sadly chapters are not supported yet in MM. MP4/M4B format does not save them as metadata (which are preserved even if unknown), it is special kind of track inside the M4B file, our encoder supports only audio track, not this text track. The only way I see now is to use some 3rd party tool to save chapters to text file, then convert files, and then add chapters back by the tool.

[Deranged Hermit]

Thanks for the answers. As the IT support person for the family, I put it to a vote, and family members prefer chapters over having twice as many books on their phones, so I dropped re-encoding the audio.

Although I prefer MMA overall as a player, both Listen and Smart ABP both support the chapter data format in our audiobooks, and MMA currently doesn't, so we'll try all three for a few weeks and have another vote.

Thanks again for the clarifying info.