Re: [PATCH v1 00/19] UVC 1.5 VP8 support for uvcvideo

Paulo Assis
2013-10-10T10:27:57Z

Hi,
just want t know the current state on this series.

I'm currently adding h264 stream preview support to guvcview.
It's already working fine on uvc 1.1 cameras like the BCC950 but for
uvc 1.5 devices like the c930e it could really use some driver
support.

Bets Regards,
Paulo

2013/8/30 Pawel Osciak <posciak@chromium.org>:
> Hello everyone,
>
> This series adds support for UVC 1.5 and VP8 encoding cameras to the uvcvideo
> driver. The official specification for the new standard can be found here:
> http://www.usb.org/developers/devclass_docs.
>
> The main change in 1.5 is support for encoding cameras. Those cameras contain
> additional UVC entities, called Encoding Units, with their own set of controls
> governing encode parameters. Typical encoding cameras (see examples in class
> spec) expose two USB Video Streaming Interfaces (VSIs): one for raw stream
> formats and one for encoded streams. Typically, both get their source stream
> from a single sensor, producing raw and encoded versions of the video feed
> simultaneously.
> Encoding Units may also support the so-called "simulcast" formats, which allow
> additional sub-streams, or layers, used to achieve temporal scalability.
> The spec allows up to 4 simulcast layers. Those layers are encoded in the same
> format, but encoding parameters, such as resolution, bitrate, etc., may,
> depending on the camera capabilities, be changed independently for each layer,
> and their streaming state may also be controlled independently as well. The
> layers are streamed from the same USB VSI, and the information which layer
> a frame belongs to is contained in its payload header.
>
> In V4L2 API, a separate video node is created for each VSI: one for raw formats
> VSI and another for the encoded formats VSI. Both can operate completely
> independently from each other. In addition, if the Encoding Unit supports
> simulcast, one V4L2 node is created for each stream layer instead, and each
> can be controlled independently, including streamon/streamoff state, setting
> resolution and controls. Once a simulcast format is successfully set for one
> of the simulcast video nodes however, it cannot be changed, unless all connected
> nodes are idle, i.e. they are not streaming and their buffers are freed.
>
> The userspace can discover if a set of nodes belongs to one encoding unit
> by traversing media controller topology of the camera.
>
>
> I will be gradually posting documentation changes for new features after initial
> rounds of reviews. This is a relatively major change to the UVC driver and
> although I tried to keep the existing logic for UVC <1.5 cameras intact as much
> as possible, I would very much appreciate it if these patches could get some
> testing from you as well, on your own devices/systems.
>
> Thanks,
> Pawel Osciak
>
>
> Pawel Osciak (19):
> uvcvideo: Add UVC query tracing.
> uvcvideo: Return 0 when setting probe control succeeds.
> uvcvideo: Add support for multiple chains with common roots.
> uvcvideo: Create separate debugfs entries for each streaming interface.
> uvcvideo: Add support for UVC1.5 P&C control.
> uvcvideo: Recognize UVC 1.5 encoding units.
> uvcvideo: Unify error reporting during format descriptor parsing.
> uvcvideo: Add UVC1.5 VP8 format support.
> uvcvideo: Reorganize uvc_{get,set}_le_value.
> uvcvideo: Support UVC 1.5 runtime control property.
> uvcvideo: Support V4L2_CTRL_TYPE_BITMASK controls.
> uvcvideo: Reorganize next buffer handling.
> uvcvideo: Unify UVC payload header parsing.
> v4l: Add v4l2_buffer flags for VP8-specific special frames.
> uvcvideo: Add support for VP8 special frame flags.
> v4l: Add encoding camera controls.
> uvcvideo: Add UVC 1.5 Encoding Unit controls.
> v4l: Add V4L2_PIX_FMT_VP8_SIMULCAST format.
> uvcvideo: Add support for UVC 1.5 VP8 simulcast.
>
> drivers/media/usb/uvc/uvc_ctrl.c | 960 ++++++++++++++++++++++++++++++++---
> drivers/media/usb/uvc/uvc_debugfs.c | 3 +-
> drivers/media/usb/uvc/uvc_driver.c | 604 ++++++++++++++--------
> drivers/media/usb/uvc/uvc_entity.c | 129 ++++-
> drivers/media/usb/uvc/uvc_isight.c | 12 +-
> drivers/media/usb/uvc/uvc_queue.c | 25 +-
> drivers/media/usb/uvc/uvc_v4l2.c | 284 +++++++++--
> drivers/media/usb/uvc/uvc_video.c | 704 ++++++++++++++++---------
> drivers/media/usb/uvc/uvcvideo.h | 214 +++++++-
> drivers/media/v4l2-core/v4l2-ctrls.c | 29 ++
> include/uapi/linux/usb/video.h | 45 ++
> include/uapi/linux/v4l2-controls.h | 31 ++
> include/uapi/linux/videodev2.h | 8 +
> 13 files changed, 2421 insertions(+), 627 deletions(-)
> --
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