.. SPDX-License-Identifier: CC-BY-SA-4.0 .. include:: documentation-contents.rst Environment variables ===================== The libcamera behaviour can be tuned through environment variables. This document lists all the available variables and describes their usage. List of variables ----------------- LIBCAMERA_LOG_FILE The custom destination for log output. Example value: ``/home/{user}/camera_log.log`` LIBCAMERA_LOG_LEVELS Configure the verbosity of log messages for different categories (`more `__). Example value: ``*:DEBUG`` LIBCAMERA_LOG_NO_COLOR Disable coloring of log messages (`more `__). LIBCAMERA_IPA_CONFIG_PATH Define custom search locations for IPA configurations (`more `__). Example value: ``${HOME}/.libcamera/share/ipa:/opt/libcamera/vendor/share/ipa`` LIBCAMERA_IPA_FORCE_ISOLATION When set to a non-empty string, force process isolation of all IPA modules. Example value: ``1`` LIBCAMERA_IPA_MODULE_PATH Define custom search locations for IPA modules (`more `__). Example value: ``${HOME}/.libcamera/lib:/opt/libcamera/vendor/lib`` LIBCAMERA_IPA_PROXY_PATH Define custom full path for a proxy worker for a given executable name. Example value: ``${HOME}/.libcamera/proxy/worker:/opt/libcamera/vendor/proxy/worker`` LIBCAMERA_PIPELINES_MATCH_LIST Define an ordered list of pipeline names to be used to match the media devices in the system. The pipeline handler names used to populate the variable are the ones passed to the REGISTER_PIPELINE_HANDLER() macro in the source code. Example value: ``rkisp1,simple`` LIBCAMERA_RPI_CONFIG_FILE Define a custom configuration file to use in the Raspberry Pi pipeline handler. Example value: ``/usr/local/share/libcamera/pipeline/rpi/vc4/minimal_mem.yaml`` LIBCAMERA_RPI_TUNING_FILE Define a custom JSON tuning file to use in the Raspberry Pi. Example value: ``/usr/local/share/libcamera/ipa/rpi/vc4/custom_sensor.json`` Further details --------------- Notes about debugging ~~~~~~~~~~~~~~~~~~~~~ The environment variables ``LIBCAMERA_LOG_FILE``, ``LIBCAMERA_LOG_LEVELS`` and ``LIBCAMERA_LOG_NO_COLOR`` are used to modify the default configuration of the libcamera logger. By default, libcamera logs all messages to the standard error (std::cerr). Messages are colored by default depending on the log level. Coloring can be disabled by setting the ``LIBCAMERA_LOG_NO_COLOR`` environment variable. The default log destination can also be directed to a file by setting the ``LIBCAMERA_LOG_FILE`` environment variable to the log file name. This also disables coloring. Log levels are controlled through the ``LIBCAMERA_LOG_LEVELS`` variable, which accepts a comma-separated list of 'category:level' pairs. The `level `__ part is mandatory and can either be specified by name or by numerical index associated with each level. The optional `category `__ is a string matching the categories defined by each file in the source base using the logging infrastructure. It can include a wildcard ('*') character at the end to match multiple categories. For more information refer to the `API documentation `__. Examples: Enable full debug output to a separate file, for every `category `__ within a local environment: .. code:: bash :~$ LIBCAMERA_LOG_FILE='/tmp/example_log.log' \ LIBCAMERA_LOG_LEVELS=0 \ cam --list Enable full debug output for the categories ``Camera`` and ``V4L2`` within a global environment: .. code:: bash :~$ export LIBCAMERA_LOG_LEVELS='Camera:DEBUG,V4L2:DEBUG' :~$ cam --list Log levels ~~~~~~~~~~ This is the list of available log levels, notice that all levels below the chosen one are printed, while those above are discarded. - DEBUG (0) - INFO (1) - WARN (2) - ERROR (3) - FATAL (4) Example: If you choose WARN (2), you will be able to see WARN (2), ERROR (3) and FATAL (4) but not DEBUG (0) and INFO (1). Log categories ~~~~~~~~~~~~~~ Every category represents a specific area of the libcamera codebase, the names can be located within the source code, for example: `src/libcamera/camera_manager.cpp /* SPDX-License-Identifier: BSD-2-Clause */ /* * Copyright (C) 2019, Raspberry Pi (Trading) Limited * * sdn_status.h - SDN (spatial denoise) control algorithm status */ #pragma once // This stores the parameters required for Spatial Denoise (SDN). #ifdef __cplusplus extern "C" { #endif struct SdnStatus { double noise_constant; double noise_slope; double strength; }; #ifdef __cplusplus } #endif tions for this operation are the installed system path (for example on Debian: ``/usr/local/x86_64-pc-linux-gnu/libcamera``) and the build directory. With the ``LIBCAMERA_IPA_MODULE_PATH``, you can specify a non-default location to search for IPA modules.