Possible to add chapters to single large m4b based only on silences?

[ajkessel]

I thought this was a simple use-case supported by m4b-tool, but I have been unable to figure out how to make it work. I have a long m4b with no chapter metadata. I'd like m4b-tool to add chapter marks based only on silence. I thought something like this should work:

m4b-tool chapters --adjust-by-silence -a 2500 -o book-chapters.m4b book.m4b

This reports a number of silences detected and creates book-chapters.m4b, but with no chapters.

Am I missing something basic about how this is supposed to work?

[sandreas]

Am I missing something basic about how this is supposed to work?

The chapters command is a bit misleading, because it modifies chapters and does not create them out of thin air. However, you could try to use the merge command with --no-conversion to prevent lowering the quality, because merge will try to create chapters.

m4b-tool merge book.m4b -o book_chapterized.m4b --no-conversion --max-chapter-length=300,900

See https://github.com/sandreas/m4b-tool/?tab=readme-ov-file#by-length for details.

[ajkessel]

m4b-tool merge book.m4b -o book_chapterized.m4b --no-conversion --max-chapter-length=300,900

doesn't create any chapters for me. I've had no problems creating chapters when merge is actually merging separate files, each one a chapter, but here I'm starting with a single monolithic m4b with no chapter markers, and I don't see how to chapterize it with m4b-tool.

[sandreas]

Ok that's strange. I look at this asap