Commit Graph

11 Commits

Author SHA1 Message Date
Nicolas Dufresne d343326d28 gst: libcamerasrc: Push segment event
Now that we have stream-start and caps, we can now push a segment event to
announce what time will our buffer correlate to. For live sources this is just
an open segment in time format.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 2575b49160 gst: libcamerasrc: Implement minimal caps negotiation
This is not expected to work in every possible cases, but should be sufficient as
an initial implementation. What it does is that it turns the StreamFormats into
caps and queries downstream caps with that as a filter.

The result is the subset of caps that can be used. We then keep the first
structure in that result and fixate using the default values found in
StreamConfiguration as a default in case a range is available.

We then validate this configuration and turn the potentially modified
configuration into caps that we push downstream. Note that we trust the order
in StreamFormats as being sorted best first, but this is not currently in
libcamera. A todo has been added in the head of this file as a reminder to fix
that in the core.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne e5f4398c19 gst: libcamerasrc: Send stream start event
Prior to sending caps, we need to send a stream-start event. This requires
generating a stream and a group id. The stream id is random for live sources and
the group id is shared across all pads.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 6d69661c24 gst: libcamerasrc: Store the srcpad in a vector
This will allow implementing generic algorithm even if we cannot
request pads yet.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 1d8cbaf214 gst: libcamerasrc: Add a task for the streaming thread
Use a GstTask as our internal streaming thread. Unlike GstBaseSrc, we
will be running a streaming thread at the element level rather than
per pad. This is needed to combine buffer request for multiple pads.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 58feb69f85 gst: libcamerasrc: Implement selection and acquisition
This adds code to select and acquire a camera. With this, it is now
possible to run a pipeline like:

   gst-launch-1.0 libcamerasrc ! fakesink

Though no buffer will be streamed yet. In this function, we implement the
change_state() virtual method to trigger actions on specific state transitions.
Note that we also return GST_STATE_CHANGE_NO_PREROLL in
GST_STATE_CHANGE_READY_TO_PAUSED and GST_STATE_CHANGE_PLAYING_TO_PAUSED
transitions as this is required for all live sources.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne cfa61225a4 gst: libcamerasrc: Add a debug category
This will allow selecting libcamerasrc traces with the following
environment:

  GST_DEBUG=libcamerasrc:7

Or all libcamera GStreamer element traces using

  GST_DEBUG="libcamera*:7"

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 2c93810ec1 gst: libcamerasrc: Add camera-name property
This property will be used to select by name the camera to use.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 26c923a27c gst: libcamerasrc: Allocate and add static pad
This pad will always be present and will allow simple pipeline to be used to
stream from the camera.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 71a28f9593 gst: Add pads to the source
This simply adds the boiler plate for pads on the source element. The
design is that we have one pad, called "src", that will always be
present, and then more pads can be requested prior in READY or less
state. Initially pads have one property "stream-role" that let you
decide which role this pad will have.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:45 +02:00
Nicolas Dufresne 17cccc68a8 Add GStreamer plugin and element skeleton
This implements the GStreamer plugin interface and adds libcamerasrc
element feature to it. This is just enough to allow plugin
introspection.

gst-inspect-1.0 build/src/gstreamer/libgstlibcamera.so
Plugin Details:
  Name                     libcamera
  Description              libcamera capture plugin
  Filename                 build/src/gstreamer/libgstlibcamera.so
  Version                  0.0.0+1042-6c9f16d3-dirty
  License                  LGPL
  Source module            libcamera
  Binary package           libcamera
  Origin URL               https://libcamera.org

  libcamerasrc: libcamera Source

  1 features:

GST_PLUGIN_PATH=$(pwd)/build/src/gstreamer gst-inspect-1.0 libcamerasrc
Factory Details:
  Rank                     primary (256)
  Long-name                libcamera Source
  Klass                    Source/Video
  Description              Linux Camera source using libcamera
  Author                   Nicolas Dufresne <nicolas.dufresne@collabora.com

Plugin Details:
  Name                     libcamera
  Description              libcamera capture plugin
  Filename                 /home/nicolas/Sources/libcamera/build/src/gstreamer/libgstlibcamera.so
  Version                  0.0.0+1042-6c9f16d3-dirty
  License                  LGPL
  Source module            libcamera
  Binary package           libcamera
  Origin URL               https://libcamera.org

GObject
 +----GInitiallyUnowned
       +----GstObject
             +----GstElement
                   +----GstLibcameraSrc

Pad Templates:
  none

Element has no clocking capabilities.
Element has no URI handling capabilities.

Pads:
  none

Element Properties:
  name                : The name of the object
                        flags: accès en lecture, accès en écriture, 0x2000
                        String. Default: "libcamerasrc0"
  parent              : The parent of the object
                        flags: accès en lecture, accès en écriture, 0x2000
                        Object of type "GstObject"

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[Silence -Wunused-function warning for older GLib versions]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-03-07 01:57:42 +02:00