Opened 14 months ago

Closed 14 months ago

Last modified 14 months ago

#8872 closed enhancement (fixed)

implement Cue-Points Chunk for WAV files (RIFF)

Reported by: Christoph Rackwitz Owned by:
Priority: wish Component: avformat
Version: git-master Keywords: wav
Cc: Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

it appears to me that ffmpeg is unaware of 'cue ' chunks in wav files, for reading and writing. ffmpeg supports cues or chapter markers for other container formats.

this involves

  • a 'cue ' chunk that contains a table of timestamps (the 'fmt ' chunk may be useful to convert sample indices to times)
  • a 'list' 'adtl' chunk that contains 'labl' chunks
  • 'labl' chunks that each contain an index and a string label, which describes the given cue point

the RIFF/WAV file specification details the structures of these chunks. I suspect that this doesn't just apply to wav files but also avi files.

I'll attach a sample file that contains a few cue points.

Attachments (2)

200828-005.wav (2.3 MB ) - added by Christoph Rackwitz 14 months ago.
sample file containing cue points
200828-005.wav -- RIFF dump (2.2 KB ) - added by Christoph Rackwitz 14 months ago.
"free form" text description of the file's structure, contains decoded cue points and labl chunks

Change History (8)

by Christoph Rackwitz, 14 months ago

Attachment: 200828-005.wav added

sample file containing cue points

by Christoph Rackwitz, 14 months ago

Attachment: 200828-005.wav -- RIFF dump added

"free form" text description of the file's structure, contains decoded cue points and labl chunks

comment:1 by Christoph Rackwitz, 14 months ago

I've found one other file where the adtl list contains not just labl chunks but also note and ltxt chunks. the note chunks contained empty strings. the ltxt chunks contained an rgn purpose.

comment:2 by Carl Eugen Hoyos, 14 months ago

Keywords: wav added
Priority: normalwish

comment:3 by Elon Musk, 14 months ago

I posted a patch to resolve this on devel mailing list.

comment:4 by Elon Musk, 14 months ago

Resolution: fixed
Status: newclosed

comment:5 by Christoph Rackwitz, 14 months ago

thanks! very nice!

comment:6 by Carl Eugen Hoyos, 14 months ago

Component: undeterminedavformat
Version: unspecifiedgit-master
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