NaiveSemanticFrameSelector.m

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%%   This file is part of SemanticFastForward_EPIC@ECCVW.
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classdef NaiveSemanticFrameSelector < CandidateFrameSelector 
    %NaiveFrameSelector selects output frames based on which frames have
    %more faces
    
    properties
        SemanticData; %Detected semantic data
    end
    
    methods
        function obj = NaiveSemanticFrameSelector (cfg, SemanticData)
            obj = obj@CandidateFrameSelector (cfg);
            obj.SemanticData = SemanticData;
        end
        
        function frame_indices = selectFrames (obj, ~, ~, ~)
            number_of_frames = obj.cfg.get('endInd')-obj.cfg.get('startInd')+1;
            %Sort detected semantics in descend order
            Semantic_Value = cell(obj.cfg.get('endInd')-obj.cfg.get('startInd')+1, 1);
            obj.SemanticData = obj.SemanticData(obj.cfg.get('startInd'):obj.cfg.get('endInd'));
            Semantic_Value(:) = {0};%Initializes the cell
            for i=1:size(obj.SemanticData,1)
                Semantic_Value{i} = FrameSemanticValue(obj.SemanticData{i});
            end
            [dummy, Index] = sort(cellfun(@double, Semantic_Value(:)), 'descend');
            %Select the frames which contain the most faces
            frame_indices = sort(Index(1:round(number_of_frames/obj.cfg.get('FastForwardSkipRatio'))));
        end
        
    end
    
end