VideoCapture Direct Show. Added getter for CV_CAP_PROP_CONVERT_RGB, CAP_PROP_CHANNEL properties. (#14592)
* Added getter for CV_CAP_PROP_CONVERT_RGB, CAP_PROP_CHANNEL properties.
Some refactoring.
* One space less.
Do not use compound literals (fix MSVC C4576) (#14276)
* do not use compound literals (compat cpp98)
* only fix msvc path
* remove unnecessary cplusplus check
According to the gstreamer docs [1], the GstMessage pointer returned by
gst_bus_pop() is nullable, meaning NULL is a valid return value.
Previously, gst_is_missing_plugin_message would throw an assert when its
message object parameter would fail the GST_IS_MESSAGE macro check,
crashing the entire process (unless running in a try-catch block of course).
Instead of relying on valid messages, check if the message object itself is
valid before passing it to other gstreamer functions.
[1] https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBus.html#gst-bus-pop
Signed-off-by: Christopher N. Hesse <raymanfx@gmail.com>
* Enabled -Wnarrowing warning
* Fixed type narrowing issues
* Cast python constants
* Use long long for python constants
* Use int for python constants with fallback to long
* Update cv2.cpp
* videoio(librealsense): fix pipeline start with config
fix to apply pipeline settings by passing config to start.
* videoio(librealsense): add support get props
add support get some props.
cap_libv4l depends on an external library (libv4l) yet is still larger
(1966 loc vs 1822 loc).
It was initially introduced copy pasting cap_v4l in order to offload
various color conversions to libv4l.
However nowadays we handle most of the needed color conversions inside
OpenCV. Our own implementation is better tested and (probably) also
better performing. (as it can optionally leverage IPP/ OpenCL)
Currently cap_v4l is better maintained and generally the code is in
better shape. There is however an API
difference in getting unconverted frames:
* on cap_libv4l one need to set `CV_CAP_MODE_GRAY=1` or
`CV_CAP_MODE_YUYV=1`
* on cap_v4l one needs to set `CV_CAP_PROP_CONVERT_RGB=0`
the latter is more flexible though as it also allows accessing undecoded
JPEG images.
fixes#4563