The DarkHelp Server is an application that runs in the backgroud and waits for images to run inference.

DarkHelp Server is configured using a JSON file. When you run DarkHelp Server without any parameters, the default JSON file is shown. It looks like this:

{
    "darkhelp": {
        "lib": {
            "network": {
                "cfg": "example.cfg",
                "names": "example.names",
                "weights": "example_best.weights"
            },
            "settings": {
                "annotation": {
                    "auto_hide_labels": true,
                    "font_scale": 0.5,
                    "font_thickness": 1,
...

The fields in the JSON configuration file are:

JSON	Example	Description
`darkhelp/lib/network/cfg`	`example.cfg`	DarkHelp::Config::cfg_filename
`darkhelp/lib/network/names`	`example.names`	DarkHelp::Config::names_filename
`darkhelp/lib/network/weights`	`example_best.weights`	DarkHelp::Config::weights_filename
`darkhelp/lib/settings/annotation/auto_hide_labels`	`true`	DarkHelp::Config::annotation_auto_hide_labels
`darkhelp/lib/settings/annotation/shade_predictions`	`0.25`	DarkHelp::Config::annotation_shade_predictions
`darkhelp/lib/settings/annotation/include_all_names`	`true`	DarkHelp::Config::include_all_names
`darkhelp/lib/settings/annotation/font_scale`	`0.5`	DarkHelp::Config::annotation_font_scale
`darkhelp/lib/settings/annotation/font_thickness`	`1`	DarkHelp::Config::annotation_font_thickness
`darkhelp/lib/settings/annotation/include_duration`	`true`	DarkHelp::Config::annotation_include_duration
`darkhelp/lib/settings/annotation/include_timestamp`	`false`	DarkHelp::Config::annotation_include_timestamp
`darkhelp/lib/settings/general/debug`	`false`	DarkHelp::Config::enable_debug
`darkhelp/lib/settings/general/driver`	`darknet` `opencv` `opencvcpu`	DarkHelp::EDriver
`darkhelp/lib/settings/general/fix_out_of_bound_values`	`true`	DarkHelp::Config::fix_out_of_bound_values
`darkhelp/lib/settings/general/modify_batch_and_subdivisions`	`true`	DarkHelp::Config::modify_batch_and_subdivisions
`darkhelp/lib/settings/general/names_include_percentage`	`true`	DarkHelp::Config::names_include_percentage
`darkhelp/lib/settings/general/non_maximal_suppression_threshold`	`0.45`	DarkHelp::Config::non_maximal_suppression_threshold
`darkhelp/lib/settings/general/sort_predictions`	`0`	DarkHelp::Config::sort_predictions (`0` = unsorted, `1` = ascending, `2` = descending)
`darkhelp/lib/settings/general/threshold`	`0.5`	DarkHelp::Config::threshold
`darkhelp/lib/settings/tiling/combine_tile_predictions`	`true`	DarkHelp::Config::combine_tile_predictions
`darkhelp/lib/settings/tiling/enable_tiles`	`false`	DarkHelp::Config::enable_tiles
`darkhelp/lib/settings/tiling/only_combine_similar_predictions`	`true`	DarkHelp::Config::only_combine_similar_predictions
`darkhelp/lib/settings/tiling/tile_edge_factor`	`0.25`	DarkHelp::Config::tile_edge_factor
`darkhelp/lib/settings/tiling/tile_rect_factor`	`1.2`	DarkHelp::Config::tile_rect_factor
`darkhelp/server/settings/camera/buffersize`	`3`	When a digital camera is used for input, this determines the number of image buffers OpenCV should attempt to use.
`darkhelp/server/settings/camera/fps`	`30`	When a digital camera is used for input, this determines the FPS OpenCV should attempt to use.
`darkhelp/server/settings/camera/height`	`480`	When a digital camera is used for input, this determines the image height OpenCV should attempt to use.
`darkhelp/server/settings/camera/name`	`/dev/video0` `3`	When a digital camera is used for input, this determines the device name OpenCV should attempt to use. If the name is a digit, then it is converted to `int` and the camera with that index is opened.
`darkhelp/server/settings/camera/save_original_image`	`true`	When a digital camera is used for input, this determines if the original video frame will be saved in the output directory.
`darkhelp/server/settings/camera/width`	`640`	When a digital camera is used for input, this determines the image width OpenCV should attempt to use.
`darkhelp/server/settings/clear_output_directory_on_startup`	`true`	If old images might remain in the input directory, this can be set to `true` to force all those images to be deleted. If set to `false` then those old images will be processed as soon as the DarkHelp Server starts.
`darkhelp/server/settings/crop_and_save_detected_objects`	`false`	When set to `true`, all the objects detected during inference will be cropped and saved in the output directory.
`darkhelp/server/settings/exit_if_idle`	`false`	When set to `true`, DarkHelp Server will exit once there are no images left to process. Also see `idle_time_in_seconds`.
`darkhelp/server/settings/idle_time_in_seconds`	`60`	When `exit_if_idle` is set to `true`, this value determines how long DarkHelp Server waits before exiting.
`darkhelp/server/settings/input_directory`	`/tmp/darkhelpserver/input`	This is the directory DarkHelp Server uses to find new images. Once an image is moved into this folder, the Server will pick it up and run inference on it, storing the results as configured.
`darkhelp/server/settings/max_images_to_process_at_once`	`10`	The maximum number of images from the input directory that are processed before `run_cmd_after_processing_images` is called.
`darkhelp/server/settings/output_directory`	`/tmp/darkhelpserver/output`	This is the directory DarkHelp Server uses to store results and annotations.
`darkhelp/server/settings/purge_files_after_cmd_completes`	`true`	When set to `true`, all the files in `output_directory` will be deleted
`darkhelp/server/settings/run_cmd_after_processing_images`		The name of an external application or script which is called every once in a while after images have been processed.
`darkhelp/server/settings/save_annotated_image`	`false`	When set to `true`, images will be annotated using DarkHelp and saved in the output directory.
`darkhelp/server/settings/save_json_results`	`true`	When set to `true`, the results of inference in JSON format will be saved in the output directory.
`darkhelp/server/settings/save_txt_annotations`	`false`	When set to `true`, the annotations in Darknet format will be saved in the output directory.
`darkhelp/server/settings/use_camera_for_input`	`false`	When set to `false`, this means images will be loaded from `output_directory`. When set to `true`, this means images will be loaded from the digital camera.

So once the settings are saved to a JSON file, start DarkHelp Server like this:

DarkHelpServer settings.json

Note that the JSON file isn't required to have all the settings in it. Only the ones that differ from the default values listed in the table above. For example, if your JSON file looks like this:

{
    "darkhelp": {
        "lib":{
            "network": {
                "cfg": "/home/stephane/nn/driving/driving.cfg",
                "names": "/home/stephane/nn/driving/driving.names",
                "weights": "/home/stephane/nn/driving/driving_best.weights"
            }
        },
        "server": {
            "settings": {
                "exit_if_idle":true,
                "idle_time_in_seconds":600,
                "save_json_results":true,
                "run_cmd_after_processing_images":"/home/stephane/bin/images_done.sh"
            }
        }
    }
}

Those settings would then be merged with the default values, and the combined settings are also shown on the console when DarkHelp Server starts running.