Hi Mark, On Mon, Jun 08, 2015 at 10:37:33 -0700, Mark Edwards wrote: > i have been using this npm module: npmjs(dot)com/package/waveform-util > and this npm module creates waveform numeric output such as this below: > [0,0.0062,0.0688,0.2524,0.2691,0.2645,0.1594,0.1397,0.1672
You should have elaborated on what those numbers mean, or what this module does. It took me a minute to figure it out - it (probably) created waveform images something like those used by SoundCloud? > however, this module does not seem reliable and has not been maintained for > a couple of years now. the module describes itself as a "tiny wrapper > around ffprobe". If it's so tiny, I don't see why it should be unreliable, and why it should be maintained. Reliability: I don't know the exact specifications for such a waveform, but to me, it's just parsing, math, visualization. Maintenance: Algorithms shouldn't change, so probably only the ffprobe interface. > my question - what would the command line look like to produce such output? Isn't that exactly what the "tiny wrapper" would expose? I wouldn't have though ffprobe can do this. Isn't this a numerical representation of the peak volume throughout a certain period of time? I _believe_ ffprobe operates frame by frame, not sample by sample or over periods of time. _I_ would have used ffmpeg's "volumedetect" filter over periods of time (-ss <N * interval> -t <interval), and used/displayed the intervals' peaks - if that's how the waveform is specified. Or I would have exported the intervals to raw audio data and sampled for maximum values myself, perhaps using e.g. perl's unpack(). Just my thoughts, Moritz _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
