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    SubjectRe: v4l interface questions
    Date
    Pavel Machek wrote:
    > Hi!
    >
    > I have few questions about v4l api.
    >
    > I have device (vicam == usb 3com homeconnect camera), which would like to
    > fit into v4l framework. But... mmap is not really native operation for
    > usb. Should I emulate it, or just return unsupported and expect
    > applications to use read()?

    IHMO applications should be able to fallback to read() if mmap() doesn't
    work.

    > Similar problem is there with formats. vicam has some really strange
    > formats. Should I do conversion in kernel?

    Probably. The driver should support at least one of the standard
    VIDEO_PALETTE_* formats. It is fine to pick one which comes close to
    the native format of the camera, there is no need to support _all_
    formats.

    > Is there some usermode program that can handle camera without mmap
    > ability and can support arbitrary screen sizes + 16bpp grayscale?

    8bpp grayscale should be no problem with xawtv. I'd suspect you will
    not find any app which can deal with 16bpp, there isn't even a
    VIDEO_PALETTE_* #define for this ...

    Gerd

    --
    Damn lot people confuse usability and eye-candy.
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