On Wed, 2006-10-11 at 21:08 +0900, Miha Kitič wrote: > Assuming that you will be using another device for audio which can not > be synchronized with the camera... > > I guess that the only way for you to make it work is to produce an event > that will allow you to synchronize audio and video manually. > > I think in movie making they use a small wooden board with which they > make a clicking sound just before they record a scene. I suppose if you > clap loudly near the mike before you take what you want to take (and > make sure that clap of your hands is included in the video), you will be > able to synchronize the clap of your hands with the sound track visually > (you could also hit the camera with the mike ;) .
This assumes that the camera records no sound, which is not the case for video cameras. It is much easier to synchronise two sounds with each other, very accurately: Put the two recordings in an audio track of their own in Cinelerra. Find a sentence or a sequence of sounds that stand out somewhat at the start of the recording, and put a label at a start of a particular word or peak in the sound (you can see the waveform in Cinelerra). Do the same with the other recording. Now shift one of the tracks until the labels align. Listen to the two tracks simulataneously. It helps to pan one track to the left channel and the other to the right. Shift one of the tracks until you get rid of the "echo" effect: The tracks are in perfect synch. Now verify that the external recording does not slip out of synch over time. Skip a little forward; does the "echo" sound come back? Skip to the end; are they still in synch? If the tracks do not stay in synch, you either have to make small cuts or pads now and then to realign them, or change the sample rate of the external recording _slightly_. You can change the sample rate for each meadia file in Cinelerra, in the "Info" dialog (right-click on the media thumbnail in the Media folder). This will make Cinelerra resample the sound. This is a little CPU-heavy and lossy, but it can solve the synch problem. -- Herman Robak _______________________________________________ Cinelerra mailing list [email protected] https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
