lkml.org 
[lkml]   [2017]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: media / v4l2-mc: wishlist for complex cameras (was Re: [PATCH v4 14/36] [media] v4l2-mc: add a function to inherit controls from a pipeline)
    From
    Date
    On Thu, 2017-03-16 at 10:47 +0100, Philippe De Muyter wrote:
    > On Thu, Mar 16, 2017 at 10:26:00AM +0100, Philipp Zabel wrote:
    > > On Wed, 2017-03-15 at 14:55 -0400, Nicolas Dufresne wrote:
    > > > Le mercredi 15 mars 2017 à 11:50 +0100, Philippe De Muyter a écrit :
    > > > > > I would say: camorama, xawtv3, zbar, google talk, skype. If it runs
    > > > > > with those, it will likely run with any other application.
    > > > > >
    > > > >
    > > > > I would like to add the 'v4l2src' plugin of gstreamer, and on the
    > > > > imx6 its
    > > >
    > > > While it would be nice if somehow you would get v4l2src to work (in
    > > > some legacy/emulation mode through libv4l2),
    > >
    > > v4l2src works just fine, provided the pipeline is configured manually in
    > > advance via media-ctl.
    >
    > Including choosing the framerate ? Sorry, I have no time these days
    > to test it myself.

    No, the framerate is set with media-ctl on the CSI output pad. To really
    choose the framerate, the element would indeed need a deeper
    understanding of the pipeline, as the resulting framerate depends on at
    least the source v4l2_subdevice (sensor) framerate and the CSI frame
    skipping.

    > And I cited imxv4l2videosrc for its ability to provide the physical address
    > of the image buffers for further processing by other (not necessarily next
    > in gstreamer pipeline, or for all frames) hardware-accelerated plugins likes
    > the h.264 video encoder. As I am stuck with fsl/nxp kernel and driver on that
    > matter, I don't know how the interfaces have evolved in current linux kernels.

    The physical address of the image buffers is hidden from userspace by
    dma-buf objects, but those can be passed around to the next driver
    without copying the image data.

    regards
    Philipp

    \
     
     \ /
      Last update: 2017-03-16 11:05    [W:4.309 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site