function conf = rcnn_config(varargin)

% Set up configuration variables.

% conf = rcnn_config(varargin)

%

% Each variable is named by a path that identifies a field

% in the returned conf structure. For example, 'foo.bar'

% corresponds to conf.foo.bar. You can set configuration

% variables in 3 ways:

% 1) File: directly editing values in this file

% 2) Per-call: pass an override as an argument to this function

% E.g., conf = rcnn_config('foo', 'bar');

% 3) Per-session: assign the global variable RCNN_CONFIG_OVERRIDE

% to a function that returns a conf structure with specific

% overrides set. This method is persistent until RCNN_CONFIG_OVERRIDE

% is cleared.

% E.g., you could put this code in a function to programmatically

% override the config.

%

% global RCNN_CONFIG_OVERRIDE;

% conf_override.exp_dir = '/path/to/experiment_directory';

% RCNN_CONFIG_OVERRIDE = @() conf_override;

% AUTORIGHTS

% ---------------------------------------------------------

% Copyright (c) 2014, Ross Girshick

%

% This file is part of the R-CNN code and is available

% under the terms of the Simplified BSD License provided in

% LICENSE. Please retain this notice and LICENSE if you use

% this file (or any portion of it) in your project.

% ---------------------------------------------------------

% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

% Defaults config (override in rcnn_config_local.m)

% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

% If you want to override any of these, create a **script**

% named rcnn_config_local.m and redefine these variables there.

% Experiments directory. The directory under which most outputs

% generated by running this code will go.

EXP_DIR = './cachedir';

% Set to false if you do not want to use a GPU.

USE_GPU = true;

% Load local overrides if rccn_config_local.m exists

% See rcnn_config_local.example.m for an example

if exist('rcnn_config_local.m')

rcnn_config_local;

end

% ~~~~~~~~~~~~~~~~~~~~~~ ADVANCED SETUP BELOW ~~~~~~~~~~~~~~~~~~~~~~

%

% conf top-level variables

%

% To set a configuration override file, declare

% the global variable RCNN_CONFIG_OVERRIDE

% and then set it as a function handle to the

% config override function. E.g.,

% >> global RCNN_CONFIG_OVERRIDE;

% >> RCNN_CONFIG_OVERRIDE = @my_rcnn_config;

% In this example, we assume that you have an M-file

% named my_rcnn_config.m.

%

% Overrides passed in as arguments have the highest precedence.

% Overrides in the overrides file have second highest precedence,

% but are clobbered by overrides passed in as arguments.

% Settings in this file are clobbered by the previous two.

% Configuration structure

conf = [];

% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

%

% Persistent and per-call overrides

%

% Check for an override configuration file

assert_not_in_parallel_worker();

global RCNN_CONFIG_OVERRIDE;

if ~isempty(RCNN_CONFIG_OVERRIDE)

conf = RCNN_CONFIG_OVERRIDE();

end

% Clobber with overrides passed in as arguments

for i = 1:2:length(varargin)

key = varargin{i};

val = varargin{i+1};

eval(['conf.' key ' = val;']);

end

% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

conf = cv(conf, 'use_gpu', USE_GPU);

conf = cv(conf, 'exp_dir', EXP_DIR);

conf = cv(conf, 'sub_dir', '');

conf = cv(conf, 'cache_dir', fullfile(conf.exp_dir, conf.sub_dir, '/'));

mkdir_if_missing(conf.cache_dir);

% -------------------------------------------------------------------

% Helper functions

% -------------------------------------------------------------------

% -------------------------------------------------------------------

% Does nothing if conf.key exists, otherwise sets conf.key to val

function conf = cv(conf, key, val)

try

eval(['conf.' key ';']);

catch

eval(['conf.' key ' = val;']);

end

% -------------------------------------------------------------------

% Throw an error if this function is called from inside a matlabpool

% worker.

function assert_not_in_parallel_worker()

% Matlab does not support accessing global variables from

% parallel workers. The result of reading a global is undefined

% and in practice has odd and inconsistent behavoir.

% The configuraton override mechanism relies on a global

% variable. To avoid hard-to-find bugs, we make sure that

% rcnn_config cannot be called from a parallel worker.

t = [];

if usejava('jvm')

try

t = getCurrentTask();

catch

end

end

if ~isempty(t)

msg = ['rcnn_config() cannot be called from a parallel worker ' ...

'(or startup.m did not run -- did you run matlab from the ' ...

'root of the rcnn installation directory?'];

error(msg);

end