tor, 17 03 2005 kl. 14:24 +0100, skrev Stephan Kanthak: > > I use oss. I haven't investigated alsa since I got confused the first > > time, however with your recommendation I'll give it another go. Can you > > possibly recommend som options for mencoder? > > for now I use: adevice=/dev/dsp0:audiorate=44100:buffersize=64 > > using oss emulation and alsa drivers. > > I let mencoder read directly from the tv card. My config is > > adevice=/dev/dsp2:audiorate=32000:forceaudio:forcechan=1:buffersize=64 > > where /dev/dsp2 is the audio device from the second analog tv card (i > actually use 2 to support live tv and record at the same time). Note, that > if you do that (it should work for at least bt8x8 and saa7134 based cards) > you are tailored to a small set of sampling rates you can choose from (usually > 32000 and 48000). I've chosen 32000 as there were some problems with 48000 > and analog tv audio bandwidth is at 15000 here in Germany anyway, so 32000 > should be fairly enough. Note that direct sampling from the tv card should > result in synchronized audio and video, whereas the usual pass-through > cable adds some delay. > > Stephan
I tried with alsa now, which does not remove the delay. If maybe reducing it a bit, but I'm unable to measure. Ano should note the tha alsa devices (in mplayer anyway) is denoted different from oss, namely: adevice=/dev/dsp0 corresponds to: alsa:adevice=hw.0,0 You may wish to try this, as it reduced the cpuload of mencoder by a couple of percent. I also tried using direct sampling from my audioboard, unfortunatly it seems audio is not possible from my board even though I can load the snd-bt87x driver and access the mixer of the board, mencoder starts to drop frames since it complains about not getting anough audio samples :( As for the cables I would assume the delay added by those would be either neglectable or constant, since I suppose its sampling delay of the A/D converter on the Live board, and they usually dont have buffers, and the sound is by no means distorted. - Jesper -- PGP/GnuPG key available at http://www.control.aau.dk/~jsma00/pgpkey.txt
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