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



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