Reduce start-capture workload by moving the elements' state reseting to the
finishing steps of the capture. This reduces the time start-capture takes to
actually start a capture and return to its caller, improving user experience.
As the elements' state reset is now triggered from the message handling
function, it needs to spawn a new thread, changing state from the pad's
task would cause a deadlock.
Adds a new variable to keep track of the state of the video
recording in camerabin2. This allows start-capture to reject
new video recording requests when one is already ongoing. This
fixes one of check tests.
Rename the image taglists' mutex into image capture mutex and
use it also for the image capture list to prevent concurrent
access from different threads (application and capture threads).
Tags are currently sent from start-capture, which is run in the
application thread. For images we can delay the tags pushing to the
buffer probe and push the tags with the location event and reduce
start-capture time.
The preview filename list is acessed whenever a new capture is started, when
camera-source posts a new preview message or on state changes. All of those can
occur simultaneously, so add a mutex to prevent concurrent access.
Makes camerabin2 intercept preview-image messages and add
the filename corresponding to the message structure in the
'location' field.
Makes easier for applications to track preview images
If we know that our camera source element produces buffers at the same
resolution and appropriate colourspace for the output, we don't need any
of the generic conversion elements in encodebin. This reduces caps
negotiation overheads among other things.
Basesrc derived classes send an eos when they change state
from paused to ready and that breaks video recordings on camerabin2
as it makes the whole audio branch pads flushing.
Prevent it by using a pad probe that only allows the eos to pass
when it is caused by a stop-capture action.
Adds a property to add a custom GstElement to the audio
branch of the pipeline. This allows the user to do custom audio
processing/analysis when recording videos.
A flags property has been added to encodebin to toggle whether the
conversion elements (ffmpegcolorspace, videoscale, audioconvert,
audioresample, audiorate) are created and linked into the appropriate
branches of encodebin.
Not including these elements avoids some slow caps negotiation and
allows the first buffers to flow through encodebin much more quickly.
However, it imposes that the uncompressed input is appropriate for the
target profile and elements selected to meet that profile.
Since camerabin2 has switched to encodebin and encodebin has its own
queues and conversion elements, those preceding encodebin are no longer
necessary and as such can be removed.
Using serialized custom events for switching image capture saving
location makes camerabin2 save each capture correctly to the location
that was set during the moment start-capture was called, and not
the moment the filesink was writing to disk.
This prevents captures to be overwriten by racyness among start-capture
and setting location for images.
This is not implemented in any of our real sources to which wrappercamerabinsrc
might connect but this is optional and can be implemented at any time. A
limit on the software zoom level using video{crop,scale} would be arbitrary.
Adds an audio source and audio capsfilter/queue/convert, creating
a new branch on camerabin2 that is used to feed encodebin with
audio buffers for video recording.
Implement previewing functionality using 2 properties. A boolean
(post-previews) that indicates if previews should be posted, and a
GstCaps (preview-caps) to provide the desired preview caps.
wrappercamerabinsrc implements previewing by supplying the captured
image to a pipeline to adapt it to the required caps before posting.
Use better name for the variables, making the code clearer. Also
keep a ref for some internal elements to avoid fetching them
by name when needed later.
We need to reset the elements from the video recording branch, including
the queue and capsfilter in order to clear the eos state and activate
the pads.
This makes it possible to record multiple videos with camerabin2 in a
sequence, otherwise the source would get a unexpected return and
push EOS, stopping the whole pipeline.
Adds a location property to enable applications to select
the captured files names. Locations are handled just like
multifilesink ones
Also disables -Wformat-nonliteral to allow to use non-literals
on g_strdup_printf on camerabin and generate a sequence of
locations for captures.
Keep vidbin state locked to avoid it going to playing without
being used and leaving an empty file created.
Check the docs on the code for details on the handling.
Removes the old logic for v4l2camerasrc that used the mode
property switching to start/stop captures to make it identical
to camerabin2 behavior and to allow the future addition of
pausing a video recording.
This also removes the MODE_PREVIEW as it became useless.
Adds mode property to camerabin2, allowing users to
select between video and stills capture. Also adds
start/stop capture actions to trigger and stop
capturing
