de5d03673c
There is a condition that would cause the buffers to never be in sync when we using only a single buffer in the bayer and embedded data streams. This occurred because even though both streams would get flushed to resync, one stream's only buffer was already queued in the device, and would end up never matching. Rework the buffer matching logic by combining updateQueue() and tryFlushQueue() into a single function findMatchingBuffers(). This would allow us to flush the queues at the same time as we match buffers, avoiding the the above condition. Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
.. SPDX-License-Identifier: CC-BY-SA-4.0
.. section-begin-libcamera
===========
libcamera
===========
**A complex camera support library for Linux, Android, and ChromeOS**
Cameras are complex devices that need heavy hardware image processing
operations. Control of the processing is based on advanced algorithms that must
run on a programmable processor. This has traditionally been implemented in a
dedicated MCU in the camera, but in embedded devices algorithms have been moved
to the main CPU to save cost. Blurring the boundary between camera devices and
Linux often left the user with no other option than a vendor-specific
closed-source solution.
To address this problem the Linux media community has very recently started
collaboration with the industry to develop a camera stack that will be
open-source-friendly while still protecting vendor core IP. libcamera was born
out of that collaboration and will offer modern camera support to Linux-based
systems, including traditional Linux distributions, ChromeOS and Android.
.. section-end-libcamera
.. section-begin-getting-started
Getting Started
---------------
To fetch the sources, build and install:
::
git clone git://linuxtv.org/libcamera.git
cd libcamera
meson build
ninja -C build install
Dependencies
~~~~~~~~~~~~
The following Debian/Ubuntu packages are required for building libcamera.
Other distributions may have differing package names:
A C++ toolchain: [required]
Either {g++, clang}
Meson Build system: [required]
meson (>= 0.51) ninja-build pkg-config
If your distribution doesn't provide a recent enough version of meson,
you can install or upgrade it using pip3.
.. code::
pip3 install --user meson
pip3 install --user --upgrade meson
for the libcamera core: [required]
python3-yaml python3-ply python3-jinja2
for IPA module signing: [required]
libgnutls28-dev openssl
for the Raspberry Pi IPA: [optional]
libboost-dev
Support for Raspberry Pi can be disabled through the meson
'pipelines' option to avoid this dependency.
for device hotplug enumeration: [optional]
libudev-dev
for documentation: [optional]
python3-sphinx doxygen graphviz
for gstreamer: [optional]
libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev
for cam: [optional]
libevent-dev
for qcam: [optional]
qtbase5-dev libqt5core5a libqt5gui5 libqt5widgets5 qttools5-dev-tools libtiff-dev
for tracing with lttng: [optional]
lttng-ust-dev python3-jinja2
Using GStreamer plugin
~~~~~~~~~~~~~~~~~~~~~~
To use GStreamer plugin from source tree, set the following environment so that
GStreamer can find it.
export GST_PLUGIN_PATH=$(pwd)/build/src/gstreamer
The debugging tool `gst-launch-1.0` can be used to construct and pipeline and test
it. The following pipeline will stream from the camera named "Camera 1" onto the
default video display element on your system.
.. code::
gst-launch-1.0 libcamerasrc camera-name="Camera 1" ! videoconvert ! autovideosink
.. section-end-getting-started