On Thursday 21 March 2002 05:24 pm, Alan Cox wrote: > (In fact for some drivers like certain USB cams once you have the user > library structure there might be no point in having a kernel mode part at > all) Mmmmm..... (dreaming of day of user space v4l drivers) > The windows world does it in user space on the whole. It often tends to > ask the driver "do this feature" and if the driver says "no" then it falls > back to library code. > > Incidentally another example of why you don't want gamma in kernel space is > that you sometimes want to be careful the order you do > filtering/gamma/scaling Absolutely. But I agree with you that I don't want to do gamma in kernel space at all. I will stand on my soap box and scream to the crowd that kernel drivers should be as light weight as possible. However every time I add something I don't want to do in the kernel to the kernel driver, the users of the driver email me congratulatory notes on how much better the driver now works with v4l apps. The current request is for a YUV420 color space conversion because apparently gnomemeeting doesn't work with RGB24. I don't want to add that, but I know the end user will be happier with the driver if I do, and the time it will take me to put in a color space conversion in the driver is likely a small fraction of what it will take to get the change into gnomemeeting.
