Hello All,

This is my first post to this project so bear with me if I am asking a question that has already been asked in the past (I searched and couldn't find anything). I have a small field recorder that lets me drop markers into the audio files as it is recording. These markers are stored inside the WAV files in the Broadcast Wave Format BWF. The files have a standard .wav extension and playback in every player I could find as normal wav files.

When I load these files into kdenlive, I notice there is an area in the audio clip properties for markers, but none of the markers created by the unit are parsed out of the file. Is parsing these markers out of the wav files supported? (ie am I doing something wrong?)

If not, I have some decent c/c++ experience along with experience in setting up complex development environments, although nothing ever with audio/video applications. I have reviewed http://www.kdenlive.org/contribution-manual/howto-develop-kdenlive already, but it will take a while before I figure out where to start...

Best Regards,

- Gerry

Not supported. As for coding it, it will be quite a challenge. I do not believe there is any way to get the info from FFmpeg, so you have to make your own MLT filter that parses the BWF and makes them into mlt_properties. Then, you will need to figure out when to apply that filter from within Kdenlive and translate those mlt_properties into GUI widgets.

Hello Dan,

Thank-you for your reply and insight. So perhaps that isn't the best way to approach it. How about being able to import/export clip markers from a text file? That way would could extract the BWF information with a separate application provide it as a simple text file. Currently audacity can import and export markers using a text file which looks something like this:

start\tfinish\tlabel\n
start\tfinish\tlabel\n
start\tfinish\tlabel\n

Audacity does not support extracting the BWF data either right now. So, I was thinking of writing a utility which, when passed a BWF .wav file would parse it and dump a text file. This way one could conceivably load the .wav into an application such as Audacity, import the labels, tune the position, perhaps re-label them, and finally re-export them. Next the user could load the .wav as an audio track into kdenlive and load up the markers in the clip markers.

This would mean adding an "import markers" button to the clip properties/markers tab, along with the code to parse out the text file.

Does that sound like a more manageable task for someone (me) to attempt? Would the feature be accepted into the truck (assuming the code passes muster)?

Best Regards,

- Gerry

Yes, that does seem quite a bit easier and a good exercise for someone new to Kdenlive code.

Although I personally have no BWF files to test, it seems that Mediainfo can read (and one day write) BWF tags:
https://sourceforge.net/projects/mediainfo/forums/forum/297609/topic/3481619/index/page/1
Perhaps it can read your markers as well? Would libmediainfo integrate into Kdenlive?

Hello,

Thank-you for pointing me in this direction! I tried the mediainfo utility. However, I could not get it to read the markers out of the wave files generated by my Zoom H2. I have posted to their forum in hopes of resolving it.

Best Regards,

- Gerry

Took some time, but I finally implemented a basic load / save feature for markers that is compatible with Audacity.

Can be found in the current git tree. To try it, go to the "Clip Properties" dialog, "Marker" tab, you now have load / save buttons.

Hi,

2015 update after 3 years. So is BWF supported now?