Use case : Image classification

Model description

Deep Layer Aggregation (DLA) networks introduce iterative and hierarchical structures for aggregating features across layers. DLA extends standard architectures by merging features from different depths and resolutions, enabling richer semantic and spatial information flow.

DLA employs Hierarchical Deep Aggregation (HDA) to merge feature hierarchies combining features from different depths, and Iterative Deep Aggregation (IDA) to progressively refine resolution and semantic information. The dense connections enable gradient flow and feature reuse across the network.

DLA is particularly well-suited for applications requiring multi-scale feature representation, such as semantic segmentation and object detection.

(source: https://arxiv.org/abs/1707.06484)

The model is quantized to int8 using ONNX Runtime and exported for efficient deployment.

Network information

Network Information	Value
Framework	Torch
MParams	~1.04–1.25 M
Quantization	Int8
Provenance	https://github.com/ucbdrive/dla
Paper	https://arxiv.org/abs/1707.06484

Network inputs / outputs

For an image resolution of NxM and P classes

Input Shape	Description
(1, N, M, 3)	Single NxM RGB image with UINT8 values between 0 and 255

Output Shape	Description
(1, P)	Per-class confidence for P classes in FLOAT32

Recommended platforms

Platform	Supported	Recommended
STM32L0	[]	[]
STM32L4	[]	[]
STM32U5	[]	[]
STM32H7	[]	[]
STM32MP1	[]	[]
STM32MP2	[]	[]
STM32N6	[x]	[x]

Performances

Metrics

• Measures are done with default STEdgeAI Core configuration with enabled input / output allocated option.
• All the models are trained from scratch on Imagenet dataset

Reference NPU memory footprint on Imagenet dataset (see Accuracy for details on dataset)

Model	Dataset	Format	Resolution	Series	Internal RAM (KiB)	External RAM (KiB)	Weights Flash (KiB)	STEdgeAI Core version
dla46xc_pt_224	Imagenet	Int8	224×224×3	STM32N6	2361	6272	1036.41	4.0.0
dla46c_pt_224	Imagenet	Int8	224×224×3	STM32N6	2361	6272	1266.66	4.0.0
dla60xc_pt_224	Imagenet	Int8	224×224×3	STM32N6	2361	6272	1278.52	4.0.0

Reference NPU inference time on Imagenet dataset (see Accuracy for details on dataset)

Model	Dataset	Format	Resolution	Board	Execution Engine	Inference time (ms)	Inf / sec	STEdgeAI Core version
dla46c_pt_224	Imagenet	Int8	224×224×3	STM32N6570-DK	NPU/MCU	184.23	5.43	4.0.0
dla46xc_pt_224	Imagenet	Int8	224×224×3	STM32N6570-DK	NPU/MCU	186.36	5.37	4.0.0
dla60xc_pt_224	Imagenet	Int8	224×224×3	STM32N6570-DK	NPU/MCU	187.54	5.33	4.0.0

Accuracy with Imagenet dataset

Dataset details: link Number of classes: 1000. To perform the quantization, we calibrated the activations with a random subset of the training set. For the sake of simplicity, the accuracy reported here was estimated on the 50000 labelled images of the validation set.

Model	Format	Resolution	Top 1 Accuracy
dla46c_pt	Float	224x224x3	65.03 %
dla46c_pt	Int8	224x224x3	64.43 %
dla46xc_pt	Float	224x224x3	66.50 %
dla46xc_pt	Int8	224x224x3	66.06 %
dla60xc_pt	Float	224x224x3	68.30 %
dla60xc_pt	Int8	224x224x3	67.73 %

Retraining and Integration in a simple example:

Please refer to the stm32ai-modelzoo-services GitHub here

References

[1] - Dataset: Imagenet (ILSVRC 2012) — https://www.image-net.org/

[2] - Model: Deep Layer Aggregation — https://github.com/ucbdrive/dla