Papers › RECALL: Replay-based Continual Learning in Semantic Segmentation

RECALL: Replay-based Continual Learning in Semantic Segmentation

8 Aug 2021ICCV 2021 10arXiv:2108.03673archive 2025-07-28

Andrea Maracani, Umberto Michieli, Marco Toldo, Pietro Zanuttigh

Deep networks allow to obtain outstanding results in semantic segmentation, however they need to be trained in a single shot with a large amount of data. Continual learning settings where new classes are learned in incremental steps and previous training data is no longer available are challenging due to the catastrophic forgetting phenomenon. Existing approaches typically fail when several incremental steps are performed or in presence of a distribution shift of the background class. We tackle these issues by recreating no longer available data for the old classes and outlining a content inpainting scheme on the background class. We propose two sources for replay data. The first resorts to a generative adversarial network to sample from the class space of past learning steps. The second relies on web-crawled data to retrieve images containing examples of old classes from online databases. In both scenarios no samples of past steps are stored, thus avoiding privacy concerns. Replay data are then blended with new samples during the incremental steps. Our approach, RECALL, outperforms state-of-the-art methods.

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lttm/recall officialmentioned in papermentioned on GitHubtfMIT report

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2ran · honoured contract
2ran · fixture could not drive it
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Model LTTM/RECALL/model_resnet.py official repository ran MIT (permissive) · a3f7331bbdb98e59 · report
add LTTM/RECALL/model_resnet.py official repository ran · honoured contract MIT (permissive) · a96ff10f26036567 · report
max_pool2d LTTM/RECALL/model_resnet.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · ded213268c033a96 · report
relu LTTM/RECALL/model_resnet.py official repository ran · honoured contract fingerprinted MIT (permissive) · 37e49142da9ee0cd · report
upsampling LTTM/RECALL/model_resnet.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · 5d9c5fe9e4c597a9 · report
ASPP LTTM/RECALL/model_resnet.py official repository unverified MIT (permissive) · 7130868dd7f4080f · report
batch_norm LTTM/RECALL/model_resnet.py official repository unverified MIT (permissive) · 54d981e50a6f3e0f · report
conv2d LTTM/RECALL/model_resnet.py official repository unverified MIT (permissive) · 22aa81d960081ea7 · report
dilated_conv2d LTTM/RECALL/model_resnet.py official repository unverified MIT (permissive) · 391774518dbd2cc0 · report
get_classes_accuracy lttm/recall/metrics.py official repository unverified MIT (permissive) · 92fa3b85dd6d9930 · report
get_classes_iou lttm/recall/metrics.py official repository unverified MIT (permissive) · 8e11a0aa76c799b6 · report
get_mean_pixel_accuracy lttm/recall/metrics.py official repository unverified MIT (permissive) · 48bc91b33344e330 · report
im2int lttm/recall/gan/generate_gan.py official repository unverified MIT (permissive) · 7045941346cccb6f · report
interleave_datasets lttm/recall/data_loader.py official repository unverified MIT (permissive) · e74234eaa6937655 · report
preprocess_training_op lttm/recall/preprocessing.py official repository unverified MIT (permissive) · 3cdee8d3ea4218a4 · report
preprocess_validation_op lttm/recall/preprocessing.py official repository unverified MIT (permissive) · 94725ecbda96c654 · report
resize_image_op lttm/recall/preprocessing.py official repository unverified MIT (permissive) · 423a14145bc09771 · report
serialize_sample lttm/recall/data_loader.py official repository unverified MIT (permissive) · 2e9c72ac0591430c · report

Tasks

Continual LearningSemantic Segmentation

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Methods

Inpainting

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