Place Recognition CNN With Trainable Feature Compression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing place recognition methods face challenges in handling condition and perspective changes, and high computational costs due to high-dimensional image features, which affect efficiency and robustness.

Innovation Solution

A method for training a place recognition model using a convolutional neural network (CNN) with integrated compression processes for parameter training, enabling end-to-end learning to obtain low-dimensional image features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If high-dimensional image features are used for place recognition, then recognition robustness is improved, but computational cost increases

Engineering Contradiction:
Improverecognition robustnessVSAvoidcomputational cost
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent extracts only the most discriminative and informative features from the image data through the CNN model, rather than processing all raw pixel information. The feature extraction process selectively identifies and retains key visual characteristics that are most relevant for place recognition, discarding redundant information that would increase computational burden without contributing to recognition accuracy.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent combines multiple feature extraction operations into a unified CNN model that performs feature extraction, selection, and aggregation in an integrated end-to-end framework. This merging of operations allows the system to achieve high-dimensional feature representation while optimizing computational efficiency through shared weights and parameter reuse across different processing stages.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If end-to-end training is implemented for place recognition, then model performance is improved, but training complexity increases

Engineering Contradiction:
Improvemodel performanceVSAvoidtraining complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the training process into distinct but interconnected components: feature extraction layers, feature aggregation layers, and loss computation layers. Each segment can be independently configured and optimized, allowing researchers to control training complexity by adjusting individual components while maintaining the benefits of end-to-end training through gradient flow across all segments.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces intermediate feature representations and loss functions that act as mediators between the input images and final recognition decisions. These intermediates provide structured pathways for gradient propagation during backpropagation, simplifying the training dynamics while enabling end-to-end optimization. The intermediate representations serve as natural checkpoints that facilitate controlled training complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3968179B1Place recognition method and apparatus, model training method and apparatus for place recognition, and electronic device
Publication Date: 2026.04.01 TENCENT TECHNOLOGY (SHENZHEN) CO LTD
  • EP3968179B1 patent drawingFigure 1~2
  • EP3968179B1 patent drawingFigure 3
  • EP3968179B1 patent drawingFigure 4~5

AI summary

Provided are a place recognition method and apparatus, a model training method and apparatus for place recognition, a computer readable storage medium and an electronic device. The model training method comprises: extracting local features of a sample image on the basis of a first portion of a CNN model (310); aggregating the local features into feature vectors having a first number of dimensions on the basis of a second portion of the CNN model (330); obtaining, on the basis of a third portion of the CNN model, compressed representation vectors of the feature vectors, wherein the compressed representation vectors have a second number of dimensions that is less than the first number of dimensions (350); and adjusting model parameters of the first to third portions with the aim of minimizing the distance between the compressed representation vectors corresponding to a plurality of images photographed at the same place (370). According to the method, a compression process with trainable parameters is introduced into a CNN model, so that an end-to-end training place recognition model can be fully realized, and the obtained CNN model can directly obtain low-dimensional image features, thereby improving the place recognition performance on the basis of artificial intelligence.