string standard - "PAL" (default) or "NTSC"
- default is based upon MLT_NORMALISATION
environment variable, which defaults to PAL.
- int frames - the number of DMA video frames. default is 4.
+ int frames - the number of DMA video frames. default is 8.
minimum is 2. maximum on my system is 11.
int buffer - the number of frames to buffer within MLT, minimum 1,
default 25.