You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: compute_error_small.m
    path of file: ./repos/OpenFace/matlab_version/experiments_JANUS
    
    the code of the file until where you have to start completion: function [ error_per_image, err_pp, err_pp_dim, frontal_ids ] = compute_error_small( ground_truth_all, detected_points_all )
%compute_error
%   compute the average point-to-point Euclidean error normalized by the
%   inter-ocular distance (measured as the Euclidean distance between the
%   outer corners of the eyes)
%
%   Inputs:
%          grounth_truth_all, size: num_of_points x 2 x num_of_images
%          detected_points_all, size: num_of_points x 2 x num_of_images

    
function [ error_per_image, err_pp, err_pp_dim, frontal_ids ] = compute_error_small( ground_truth_all, detected_points_all )
%compute_error
%   compute the average point-to-point Euclidean error normalized by the
%   inter-ocular distance (measured as the Euclidean distance between the
%   outer corners of the eyes)
%
%   Inputs:
%          grounth_truth_all, size: num_of_points x 2 x num_of_images
%          detected_points_all, size: num_of_points x 2 x num_of_images
%   Output:
%          error_per_image, size: num_of_images x 1


num_of_images = size(ground_truth_all,3);
ground_truth_all_orig = ground_truth_all;

ground_truth_all = ground_truth_all([1:60,62:64,66:end