OCA\FaceRecognition\BackgroundJob\Tasks\CreateClustersTask

Complexity

Total Complexity

57

Size/Duplication

Total Lines	348
Duplicated Lines	0 %

Test Coverage

Coverage

0%

Importance

Changes	5
Bugs	0	Features	1

8 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	13	1
A	description()	0	2	1
A	execute()	0	21	3
B	fillFaceRelationsFromPersons()	0	34	7
F	mergeClusters()	0	59	14
A	getCurrentClusters()	0	11	4
C	createClusterIfNeeded()	0	111	15
C	getNewClusters()	0	52	12

<?php
/**
 * @copyright Copyright (c) 2017-2020 Matias De lellis <mati86dl@gmail.com>
 * @copyright Copyright (c) 2018, Branko Kokanovic <branko@kokanovic.org>
 *
 * @author Branko Kokanovic <branko@kokanovic.org>
 *
 * @license GNU AGPL version 3 or any later version
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
namespace OCA\FaceRecognition\BackgroundJob\Tasks;

use OCP\IUser;

use OCA\FaceRecognition\BackgroundJob\FaceRecognitionBackgroundTask;
use OCA\FaceRecognition\BackgroundJob\FaceRecognitionContext;

use OCA\FaceRecognition\Db\FaceMapper;
use OCA\FaceRecognition\Db\ImageMapper;
use OCA\FaceRecognition\Db\PersonMapper;

use OCA\FaceRecognition\Db\Relation;
use OCA\FaceRecognition\Db\RelationMapper;

use OCA\FaceRecognition\Helper\Euclidean;

use OCA\FaceRecognition\Service\SettingsService;
/**
 * Taks that, for each user, creates person clusters for each.
 */
class CreateClustersTask extends FaceRecognitionBackgroundTask {
	/** @var PersonMapper Person mapper*/
	private $personMapper;

	/** @var ImageMapper Image mapper*/
	private $imageMapper;

	/** @var FaceMapper Face mapper*/
	private $faceMapper;

	/** @var RelationMapper Relation mapper*/
	private $relationMapper;

	/** @var SettingsService Settings service*/
	private $settingsService;

	/**
	 * @param PersonMapper
	 * @param ImageMapper
	 * @param FaceMapper
	 * @param SettingsService
	 */
	public function __construct(PersonMapper    $personMapper,
	                            ImageMapper     $imageMapper,
	                            FaceMapper      $faceMapper,
	                            RelationMapper  $relationMapper,
	                            SettingsService $settingsService)
	{
		parent::__construct();

		$this->personMapper    = $personMapper;
		$this->imageMapper     = $imageMapper;
		$this->faceMapper      = $faceMapper;
		$this->relationMapper  = $relationMapper;
		$this->settingsService = $settingsService;
	}

	/**
	 * @inheritdoc
	 */
	public function description() {
		return "Create new persons or update existing persons";
	}

	/**
	 * @inheritdoc
	 */
	public function execute(FaceRecognitionContext $context) {
		$this->setContext($context);

		// We cannot yield inside of Closure, so we need to extract all users and iterate outside of closure.
		// However, since we don't want to do deep copy of IUser, we keep only UID in this array.
		//
		$eligable_users = array();
		if (is_null($this->context->user)) {
			$this->context->userManager->callForSeenUsers(function (IUser $user) use (&$eligable_users) {
				$eligable_users[] = $user->getUID();
			});
		} else {
			$eligable_users[] = $this->context->user->getUID();
		}

		foreach($eligable_users as $user) {
			$this->createClusterIfNeeded($user);
			yield;
		}

		return true;
	}

	private function createClusterIfNeeded(string $userId) {
		// Check that we processed enough images to start creating clusters
		//
		$modelId = $this->settingsService->getCurrentFaceModel();

		$hasPersons = $this->personMapper->countPersons($userId, $modelId) > 0;

		// Depending on whether we already have clusters, decide if we should create/recreate them.
		//
		if ($hasPersons) {
			// OK, we already got some persons. We now need to evaluate whether we want to recreate clusters.
			// We want to recreate clusters/persons if:
			// * Some cluster/person is invalidated (is_valid is false for someone)
			//     This means some image that belonged to this user is changed, deleted etc.
			// * There are some new faces. Now, we don't want to jump the gun here. We want to either have:
			// ** more than 10 new faces, or
			// ** less than 10 new faces, but they are older than 2h
			//  (basically, we want to avoid recreating cluster for each new face being uploaded,
			//  however, we don't want to wait too much as clusters could be changed a lot)
			//
			$haveNewFaces = false;
			$facesWithoutPersons = $this->faceMapper->countFaces($userId, $modelId, true);
			$this->logDebug(sprintf('Found %d faces without associated persons for user %s and model %d',
				$facesWithoutPersons, $userId, $modelId));
			// todo: get rid of magic numbers (move to config)
			if ($facesWithoutPersons >= 10) {
				$haveNewFaces = true;
			} else if ($facesWithoutPersons > 0) {
				// We have some faces, but not that many, let's see when oldest one is generated.
				$face = $this->faceMapper->getOldestCreatedFaceWithoutPerson($userId, $modelId);
				$oldestFaceTimestamp = $face->creationTime->getTimestamp();
				$currentTimestamp = (new \DateTime())->getTimestamp();
				$this->logDebug(sprintf('Oldest face without persons for user %s and model %d is from %s',
					$userId, $modelId, $face->creationTime->format('Y-m-d H:i:s')));
				// todo: get rid of magic numbers (move to config)
				if ($currentTimestamp - $oldestFaceTimestamp > 2 * 60 * 60) {
					$haveNewFaces = true;
				}
			}

			$stalePersonsCount = $this->personMapper->countPersons($userId, $modelId, true);
			$haveStalePersons = $stalePersonsCount > 0;
			$staleCluster = $haveStalePersons === false && $haveNewFaces === false;

			$forceRecreation = $this->settingsService->getNeedRecreateClusters($userId);

			$this->logDebug(sprintf('Found %d changed persons for user %s and model %d', $stalePersonsCount, $userId, $modelId));

			if ($staleCluster && !$forceRecreation) {
				// If there is no invalid persons, and there is no recent new faces, no need to recreate cluster
				$this->logInfo('Clusters already exist, estimated there is no need to recreate them');
				return;
			}
			else if ($forceRecreation) {
				$this->logInfo('Clusters already exist, but there was some change that requires recreating the clusters');
			}
		} else {
			// User should not be able to use this directly, used in tests
			$forceCreation = $this->settingsService->getForceCreateClusters($userId);

			// These are basic criteria without which we should not even consider creating clusters.
			// These clusters will be small and not "stable" enough and we should better wait for more images to come.
			// todo: 2 queries to get these 2 counts, can we do this smarter?
			$imageCount = $this->imageMapper->countUserImages($userId, $modelId);
			$imageProcessed = $this->imageMapper->countUserProcessedImages($userId, $modelId);
			$percentImagesProcessed = 0;
			if ($imageCount > 0) {
				$percentImagesProcessed = $imageProcessed / floatval($imageCount);
			}
			$facesCount = $this->faceMapper->countFaces($userId, $modelId);
			// todo: get rid of magic numbers (move to config)
			if (!$forceCreation && ($facesCount < 1000) && ($imageCount < 100) && ($percentImagesProcessed < 0.95)) {
				$this->logInfo(
					'Skipping cluster creation, not enough data (yet) collected. ' .
					'For cluster creation, you need either one of the following:');
				$this->logInfo(sprintf('* have 1000 faces already processed (you have %d),', $facesCount));
				$this->logInfo(sprintf('* have 100 images (you have %d),', $imageCount));
				$this->logInfo(sprintf('* or you need to have 95%% of you images processed (you have %.2f%%)', $percentImagesProcessed));
				return;
			}
		}

		$faces = $this->faceMapper->getFaces($userId, $modelId);
		$this->logInfo(count($faces) . ' faces found for clustering');

		// Cluster is associative array where key is person ID.
		// Value is array of face IDs. For old clusters, person IDs are some existing person IDs,
		// and for new clusters is whatever chinese whispers decides to identify them.
		//
		$currentClusters = $this->getCurrentClusters($faces);
		$newClusters = $this->getNewClusters($faces);
		$this->logInfo(count($newClusters) . ' persons found after clustering');

		// New merge
		$mergedClusters = $this->mergeClusters($currentClusters, $newClusters);
		$this->personMapper->mergeClusterToDatabase($userId, $currentClusters, $mergedClusters);

		// Remove all orphaned persons (those without any faces)
		// NOTE: we will do this for all models, not just for current one, but this is not problem.
		$orphansDeleted = $this->personMapper->deleteOrphaned($userId);
		if ($orphansDeleted > 0) {
			$this->logInfo('Deleted ' . $orphansDeleted . ' persons without faces');
		}

		// Fill relation table with new clusters.
		$relations = $this->fillFaceRelationsFromPersons($userId, $modelId);
		$this->logInfo($relations . ' relations added as suggestions');

		// Prevents not create/recreate the clusters unnecessarily.
		$this->settingsService->setNeedRecreateClusters(false, $userId);
		$this->settingsService->setForceCreateClusters(false, $userId);
	}

	private function getCurrentClusters(array $faces): array {
		$chineseClusters = array();
		foreach($faces as $face) {
			if ($face->person !== null) {
				if (!isset($chineseClusters[$face->person])) {
					$chineseClusters[$face->person] = array();
				}
				$chineseClusters[$face->person][] = $face->id;
			}
		}
		return $chineseClusters;
	}

	private function getNewClusters(array $faces): array {
		// Create edges for chinese whispers
		$sensitivity = $this->settingsService->getSensitivity();
		$min_confidence = $this->settingsService->getMinimumConfidence();
		$edges = array();

		if (version_compare(phpversion('pdlib'), '1.0.2', '>=')) {
			for ($i = 0, $face_count1 = count($faces); $i < $face_count1; $i++) {
				$face1 = $faces[$i];
				if ($face1->confidence < $min_confidence) {
					$edges[] = array($i, $i);
					continue;
				}
				for ($j = $i, $face_count2 = count($faces); $j < $face_count2; $j++) {
					$face2 = $faces[$j];
					$distance = dlib_vector_length($face1->descriptor, $face2->descriptor);

The function dlib_vector_length was not found. Maybe you did not declare it correctly or list all dependencies?

					if ($distance < $sensitivity) {
						$edges[] = array($i, $j);
					}
				}
			}
		} else {
			$euclidean = new Euclidean();
			for ($i = 0, $face_count1 = count($faces); $i < $face_count1; $i++) {
				$face1 = $faces[$i];
				if ($face1->confidence < $min_confidence) {
					$edges[] = array($i, $i);
					continue;
				}
				for ($j = $i, $face_count2 = count($faces); $j < $face_count2; $j++) {
					$face2 = $faces[$j];
					// todo: can't this distance be a method in $face1->distance($face2)?
					$distance = $euclidean->distance($face1->descriptor, $face2->descriptor);

					if ($distance < $sensitivity) {
						$edges[] = array($i, $j);
					}
				}
			}
		}

		$newChineseClustersByIndex = dlib_chinese_whispers($edges);

The function dlib_chinese_whispers was not found. Maybe you did not declare it correctly or list all dependencies?

		$newClusters = array();
		for ($i = 0, $c = count($newChineseClustersByIndex); $i < $c; $i++) {
			if (!isset($newClusters[$newChineseClustersByIndex[$i]])) {
				$newClusters[$newChineseClustersByIndex[$i]] = array();
			}
			$newClusters[$newChineseClustersByIndex[$i]][] = $faces[$i]->id;
		}

		return $newClusters;
	}

	/**
	 * todo: only reason this is public is because of tests. Go figure it out better.
	 */
	public function mergeClusters(array $oldCluster, array $newCluster): array {
		// Create map of face transitions
		$transitions = array();
		foreach ($newCluster as $newPerson=>$newFaces) {
			foreach ($newFaces as $newFace) {
				$oldPersonFound = null;
				foreach ($oldCluster as $oldPerson => $oldFaces) {
					if (in_array($newFace, $oldFaces)) {
						$oldPersonFound = $oldPerson;
						break;
					}
				}
				$transitions[$newFace] = array($oldPersonFound, $newPerson);
			}
		}
		// Count transitions
		$transitionCount = array();
		foreach ($transitions as $transition) {
			$key = $transition[0] . ':' . $transition[1];
			if (array_key_exists($key, $transitionCount)) {
				$transitionCount[$key]++;
			} else {
				$transitionCount[$key] = 1;
			}
		}
		// Create map of new person -> old person transitions
		$newOldPersonMapping = array();
		$oldPersonProcessed = array(); // store this, so we don't waste cycles for in_array()
		arsort($transitionCount);
		foreach ($transitionCount as $transitionKey => $count) {
			$transition = explode(":", $transitionKey);
			$oldPerson = intval($transition[0]);
			$newPerson = intval($transition[1]);
			if (!array_key_exists($newPerson, $newOldPersonMapping)) {
				if (($oldPerson === 0) || (!array_key_exists($oldPerson, $oldPersonProcessed))) {
					$newOldPersonMapping[$newPerson] = $oldPerson;
					$oldPersonProcessed[$oldPerson] = 0;
				} else {
					$newOldPersonMapping[$newPerson] = 0;
				}
			}
		}
		// Starting with new cluster, convert all new person IDs with old person IDs
		$maxOldPersonId = 1;
		if (count($oldCluster) > 0) {
			$maxOldPersonId = max(array_keys($oldCluster)) + 1;
		}

		$result = array();
		foreach ($newCluster as $newPerson => $newFaces) {
			$oldPerson = $newOldPersonMapping[$newPerson];
			if ($oldPerson === 0) {
				$result[$maxOldPersonId] = $newFaces;
				$maxOldPersonId++;
			} else {
				$result[$oldPerson] = $newFaces;
			}
		}
		return $result;
	}

	private function fillFaceRelationsFromPersons(string $userId, int $modelId): int {
		$deviation = $this->settingsService->getDeviation();
		if (!version_compare(phpversion('pdlib'), '1.0.2', '>=') || ($deviation === 0.0))
			return 0;

		$sensitivity = $this->settingsService->getSensitivity();

		// Get the representative faces of each person
		$mainFaces = array();
		$persons = $this->personMapper->findAll($userId, $modelId);
		foreach ($persons as $person) {
			$mainFaces[] = $this->faceMapper->findRepresentativeFromPerson($userId, $modelId, $person->getId(), $sensitivity);
		}

		// Get similar faces taking into account the deviation
		$relations = array();
		$faces_count = count($mainFaces);
		for ($i = 0 ; $i < $faces_count; $i++) {
			$face1 = $mainFaces[$i];
			for ($j = $i+1; $j < $faces_count; $j++) {
				$face2 = $mainFaces[$j];
				$distance = dlib_vector_length($face1->descriptor, $face2->descriptor);

The function dlib_vector_length was not found. Maybe you did not declare it correctly or list all dependencies?

				if ($distance < ($sensitivity + $deviation)) {
					$relation = new Relation();
					$relation->setFace1($face1->getId());
					$relation->setFace2($face2->getId());
					$relation->setState(RELATION::PROPOSED);
					$relations[] = $relation;
				}
			}
		}

		// Merge new suggested relations
		return $this->relationMapper->merge($relations);
	}

}