Gerd Knorr wrote: > Depends on what exactly you need. Wakeup on every field it isn't that > trivial to do as the whole bttv irq handler is designed to be invoked > once per frame. Just filling the fields into separate captyure > buffers (i.e. V4L2_FIELD_ALTERNATE) should be easy through. Alas, the problem isn't separating fields (that's easy enough), it's latency. The extra 20ms hurts. I'll try to give you an idea of my particular problem (though there are many situations where latency is important). I'm building a system for on-stage performance where dancing controls video graphics (like VJ-ing, but controlled through dancing). The point is that music, dancing, _and_ video need to be in sync. The quality of these life performances are determined for a large part by so-called 'micro-timing'. The 30-45ms total delay you'd see with a field-rate image processing system is hardly good enough. An extra 20ms ruins much of the effect... (If you don't believe me, talk to a any professional music/video performer who uses computers;). Well, if this project takes off and brings in money, I may be able to pay you to implement field-rate capture... Would you be interested? (There is a bit of a chicken-and-egg problem here...). - Reinoud
