Ben:

I'm wondering if there is an easy way I can use an effect or similar function to display the waveform of an audio track in the compositor output (and final render).

The ffmpeg plugins that I "think" might get you what you want are all commented out in {your cinelerra path}/bin/ffmpeg/ plugin.opts file. When I uncomment these to test, they all come up with "Input/output error" and am assuming that this is because the required data is not available at the time needed. I will have to ask GG to be sure though or to see if there is a workaround using a pre-Opts file, and he is unavailable right now. If you want to test this yourself you can do so by modifying the plugin.opts file in the cinelerra bin ffmpeg directory and uincommenting and removing the #-s at the end of the line for ahistogram...showcqt... or whatever. Then delete Cinelerra_plugins in your $HOME/.bcast5 directory so that the plugins are reloaded. Start Cin from a window to see the messages instead of an application icon. gg/Phyllis ------------------ Error messages I get in Cin-GG ---------------------------- PluginFFilter::new_ffilter(ahistogram) err: Input/output error PluginFFilter::new_ffilter(aphasemeter) err: Operation not permitted PluginFFilter::new_ffilter(showcqt) err: Input/output error PluginFFilter::new_ffilter(showfreqs) err: Input/output error PluginFFilter::new_ffilter(showspectrum) err: Input/output error PluginFFilter::new_ffilter(showspectrumpic) err: Input/output error PluginFFilter::new_ffilter(showvolume) err: Input/output error PluginFFilter::new_ffilter(showwaves) err: Input/output error PluginFFilter::new_ffilter(showwavespic) err: Input/output error

Ben:

I'm wondering if there is an easy way I can use an effect or similar function to display the waveform of an audio track in the compositor output (and final render).

GG has not come up with anything but has checked into the reason for the inability to load the ffmpeg plugins that work from its command line. As is, it will not work (see Andrew's email reply or look below). He also attempted to get this working with a pre-load OPTS file but found that to be totally impractical -- it required manual intervention in the debugger to set up certain variables. If you want to do this kind of thing frequently, you could possibly set up a "shell command" within Cinelerra. The Shell Command function is the DOS-like icon in the Main window, upper right hand corner above the FF icon. There is a usage description there too and it is documented in Features5.pdf. But it is probably more work than simply using ffmpeg direct. Andrew:

Aren't those plugins somewhat special? In sense they _consume_ audio data (and thus their input must be attached to audio track) yet they _produce_ video (image) data, so their output must be connected (somehow) to video track?

You are right. GG tracked down the Input/Output error coming from ffmpeg. Like you said, the code checks for just audio or just video.