Greetings, On Tuesday 05 March 2002 16:52, you wrote: > > Basically, it would be sweet if the v4l2_buffer had a pointer on it, > > instead of an index. Then you would just capture to that pointer. > > Chris > > The problem with this approach is that there are a some corner cases > where it doesn't work that nicely: > > * If the driver has to touch the video data (which is true for many usb > cams because they have to uncompress the data) it doesn't work nicely. > Basically the driver will have to do a extra memcpy then: > copy_to_user(v4l2_buffer->ptr,kernelbuf,size). I doubt that this is ever an issue. Clearly, anyone who is using the same buffer to gather his compressed datastream *and* the uncompressed image is nuts :-) And of course the decompression engine pokes data right into the output buffer. The application is never aware of any background decompression. Just my 2 eurocents. - Nemosoft
