Am 04.04.2012 13:37, schrieb Christoph Limbach: > i have a quite specific question: i run cinelerra on avlinux and everything > is smooth, on laptop I have sound, but on my desktop pc, I use a rme > multiface card and i just can t get any sound out of it with cinelerra. I > start hdspmixer at the beginning, but nothing.
Hello Christoph, getting this stuff to work can be tricky at times, but I want to reassure you, it is possible: I am running a RME Multiface and are able to get sound out of Cinelerra. But, since several years, the only sound system that works in Cinelerra (and some other applications like MPlayer) is the damn old OSS. Both on Debian and Ubuntu, and various Cinelerra versions (custom compiled) I found ALSA to be quite problematic with several applications. But the reason to blame is neither ALSA, nor the RME / hdsp interface. The actual problem seems to be that ALSA is quite low-level and "close to the hardware". And, unfortunately, the majority of open source programmers just seem to be too lazy to get their a** up and implement the ALSA interface properly and to full extent. Usually, what's done is just to test some cheapo standard or on board interfaces and then more or less hard wire the connection logic that seemed work with those into the application. Actually, ALSA provides a comprehensive API to query the hardware interface for its capabilities. Moreover, ALSA provides a really elaborate system of automated conversions and custom configuration options. These are difficult to configure and hard to understand just from the available documentation (so this might be another reason for the ongoing problems in this area). >From my own programming efforts, I know for sure that it doesn't work just to open the RME interface from ALSA with "2 fixed channels and 16 bit integer samples". What needs to be done is to query the actual number of channels (which vary depending on your sampling rate and chosen configuration). If I recall correct its about 14 to 24 channels, and the hardware driver reports only the floating point based and the 24bit option to work, and all channels need to be opened, and all of this needs to be set on the right sub interface. At this point, the application using ALSA is required to have the "intelligence" to pick the options actually reported as working by the interface, and then run the output with the necessary conversions / repackaging. On my system, only few applications get this right. e.g. VLC (media player), Audacity (only the more recent releases) the Jack audio connection server, and the PortAudio and OSS emulation libraries. as a sidenote: with current kernels, when you choose "OSS", what you get is actually an emulation of the deprecated old OSS output by forwarding to ALSA. PortAudio is similar, but actually even another layer of abstraction on top: it automatically connects through Jack, Pulse, ESD, ALSA or OSS. > in cinelerra, also the "VU"- meters dont show any activity. I tried alsa and > other sound options.. no more ideas what i can do... First off, the VU meters in Cinelerra *must* be showing some output on playback. Otherwise, either, your video's sound tracks are in a format not understood by cinelerra, or Cinelerra wasn't able to open *any* sound output. Tip: use an uncompressed 16bit WAV file for experiments, to avoid the additional complexities with video and video formats / containers Of course, besides of that, the firmware needs to be loaded into your multiface (but usually this is done automatically on system boot, when the snd_hdsp kernel module is loaded). Important: this loading needs to happen *before* any application tries to open those interfaces. Moreover, you need to open the hdspmixer once after startup (because initially the interface is muted). Another possible pitfall is that the RME / hdsp inteface doesn't show up consistently at the same hardware interface number. In one of my former systems, I had that problem and needed to insert some configuration (I could look that up if required) in order to get it to appear as *second* interface /dev/dsp1 consistently. For me, this is what I want. My on board soundcard isn't wired in any way, so I don't get annoyed by some kindergarten software wanting to do boo-boo beep-beep. And my studio monitors, headphones and further equipment is hooked up to the various RME outputs and enabled explicitly when required. hope that helps Cheers, Hermann V. _______________________________________________ Cinelerra mailing list [email protected] https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
