C wrapper over Blackmagic Devices Decklink C++ api

A simple high level capture api a quite reduced bmdcapture leveraging it are provided. bmdcapture.cpp and the other tools will be converted later.

You need autotools, recent Decklink drivers and library and, optionally, Libav for the test programs.

./configure --with-sdkdir=/path/to/the/sdk/include
make
make install

The is an experimental branch that leverages libbmd capture to provide an avdevice. In order to enable it:

./configure --enable-libbmd

is enough.

To use it the normal avdevice way to configure the input is enough

./avconv -analyzeduration 0 -f bmd -video_mode 8 -audio_connection 2 -video_connection 4 -video_format 1 -i default ${output options}

Keep in mind that the code is in flux and the options are bound to change.

• Add some high level api for probing/enumerating devices.
• Add the equivalent simple high level api for playback.
• Provide a thin wrapper over the decklink classes.
• Document the whole thing properly