Re: [Linux-uvc-devel] Logitech Quickcam for Notebooks Pro

[Laurent P. <lau...@sk...>]

> im currently looking through the libng source code (included in the CVS
> version of aMSN, utils/linux/capture/libng), and i really dont know where
> to start. I cant find (or  just blind to) the YUYV converter in the code,
> and assuming i can find it, still not sure where to put the mjpeg decoder

Try to ask the aMSN developers.

> so are you saying, you would have to take the mjpeg stream, add the huffman
> table, decompress it into yuyv, then it would be acceptable format for the
> webcam?

The webcam produces MJPEG data (JPEG without Huffman tables). To display the 
image on screen, you need to decompress it. The user space application which 
captures the video must implement MJPEG decompression.

> if this is the case, would it not be more, um, economical, to then just
> have a userland application, which decompresses the stream, and then sends
> it back as another v4l2 device? is this even possible? if so, how do you go
> about it all?

The best solution to that problem would probably to have a v4l user-space 
library which would handle decompression in user-space (this would also have 
the benefit to make user-space drivers possible).

Laurent Pinchart