有没有这样的工具，可以变换双语片的左右声道，比如说本来的影片左边是粤语，右边是国语，那么能变成左边是国语右边是粤语吗

那man mplayer算了。这可没试过

这样变换有什么用吗？

左音箱放到右邊，右音箱放到左邊。

或者把接线反一下

不是把，我的是笔记本，只有一个外接音箱接口（就在左边那个左边喇叭旁边），所以只能发出左边喇叭的声音，右边的喇叭不能发出声音，所以想把左边的粤语和右边的国语互相换一下

mplayer可以自己定义声道的映射

你可以指定媒体的某一声道的数据送入某个音响

EXAMPLE:
mplayer -af channels=4:4:0:1:1:0:2:2:3:3 media.avi
Would change the number of channels to 4 and set up 4
routes that swap channel 0 and channel 1 and leave chan-
nel 2 and 3 intact. Observe that if media containing
two channels was played back, channels 2 and 3 would
contain silence but 0 and 1 would still be swapped.
mplayer -af channels=6:4:0:0:0:1:0:2:0:3 media.avi
Would change the number of channels to 6 and set up 4
routes that copy channel 0 to channels 0 to 3. Channel
4 and 5 will contain silence.

mplayer可以哈，看DVD和VCD的时候试过