Feature Re-Extraction for Low-SRAM Neural Network Skip Connections

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Skip connections in neural networks improve generalization performance but require significant SRAM storage space, leading to increased costs, which is undesirable for resource-constrained devices.

Innovation Solution

Implement a re-extraction process to propagate feature quantity vectors through a bypass path, avoiding the need to store them in cache memory, thus enabling skip connections without expanding SRAM usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If skip connections are implemented to improve generalization performance, then generalization performance is improved, but SRAM storage space increases leading to higher costs

Engineering Contradiction:
Improvegeneralization performanceVSAvoidSRAM storage space
Core Design Contradiction:
Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

The patent extracts the feature quantity vectors from the forward propagation path and stores them in main memory instead of cache memory. This allows the skip connection functionality to be maintained while reducing the SRAM storage space requirement from cache memory to only the minimum necessary for active computation, with historical feature vectors stored in cheaper main memory.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces main memory as an intermediary storage layer between the processing units and the skip connection mechanism. This intermediary allows feature vectors to be retained across different processing stages without requiring large cache memory, effectively decoupling the skip connection functionality from high-cost SRAM resources.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If feature quantity vectors are retained in cache memory to enable skip connections, then skip connection functionality is achieved, but circuit area and costs increase

Engineering Contradiction:
Improveskip connection functionalityVSAvoidcircuit area
Core Design Contradiction:
Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent extracts the storage function for feature quantity vectors from the cache memory system and relocates it to main memory. This separation allows the cache memory to be minimized to only what is necessary for active computation, while the bulk storage requirement for skip connections is satisfied by main memory, thereby reducing overall circuit area.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the storage dimension hierarchy by moving feature vector storage from the fast but expensive cache memory dimension to the slower but cheaper main memory dimension. This dimensional transition in the memory hierarchy allows skip connection functionality to be maintained while reducing the footprint in the critical cache memory dimension.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Quantity of substance

If SRAM storage space is not increased to reduce costs, then costs are reduced, but storage space for processing results becomes insufficient

Engineering Contradiction:
ImproveSRAM storage spaceVSAvoidstorage sufficiency
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent introduces main memory as an intermediary storage layer that supplements the limited SRAM cache memory. This intermediary provides additional storage capacity for feature quantity vectors needed by skip connections, ensuring storage sufficiency without requiring an increase in expensive SRAM resources.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the storage requirement into two parts: a small portion in SRAM cache memory for actively computed feature vectors, and a larger portion in main memory for historical feature vectors needed by skip connections. This segmentation allows the system to meet total storage requirements while keeping SRAM usage minimal.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS20250299043A1Information processing apparatus, information processing method, and storage media
Publication Date: 2025.09.25 CANON KK
  • US20250299043A1 patent drawing
  • US20250299043A1 patent drawing
  • US20250299043A1 patent drawing

AI summary

An information processing apparatus includes at least one memory storing a plurality of convolution layers and a processor connected to the at least one memory. The processor propagates output data based on a feature quantity vector extracted from input data from a preceding stage side at each convolution layer to a subsequent stage side; concatenates a forward propagation path with a bypass path that bypasses the forward propagation path; performs processing of extracting the feature quantity vector from the input data at each convolution layer; in the processing of extracting the feature quantity vector, performs, as re-extraction processing, processing of re-extracting the feature quantity vectors included in convolution layers up to a convolution layer where bypassing through the bypass path starts; and in a case where the re-extraction processing is performed, concatenates an output result from the forward propagation path with a result of the re-extraction processing.