DGert Vervoort writes: > V4L2 can deal perfectly with a MPEG compressed stream. At work I have a I think Marcus mainly wanted to refer to playback. There are some commands in V4L but not much in V4L2. > prototype board running with a SAA7134 PCI bridge/video decoder and a > SAA6752 MPEG-2 encoder. It uses the SAA7134 driver: > http://bytesex.org/saa7134/ . > I initialise the MPEG encoder via the I2C user space device and then I > can read a transport stream from the card, by just simply reading from a > V4L2 device: > > cat /dev/video1 | mpeg2dec -t 0x100 > > And this is exactly what a kernel space driver should do; just pass a > compressed stream to user space. The DVB API adds mux/demux > functionality to kernel space, but this is clearly a user space issue > instead of a kernel space issue. The problem is that you then would have to implement the DVB network device in userspace. Possible, but more complicated and it adds unnecessary overhead if the DVB card can filter in hardware. It is similar to the situtation with network cards where some have many hardware multicast filters and others where you might have to use promiscuous mode and software filters. Ralph
