2. ■ Comparison: R-CNN vs Fast R-CNN
■ Image Pyramid
■ Scale Invariance (Multi-scale)
■ Truncated SVD for replacing weights of FC layers
■ Performance Metric: Pascal VOC 2012 vs COCO
Outline
2
3. Comparision: R-CNN vs Fast R-CNN
3
■ R-CNN
□ Architecture
□ Classification
□ Regression (localization)
-> BBOX encoding: for reducing the answer space.
It can be further reduced by variance trick
X
4. Comparision: R-CNN vs Fast R-CNN
4
■ R-CNN
□ Defacts
□ Multi-stage training pipeline
(1) Train ConvNet for localization
(2) Train SVMs to ConvNet features
(3) Replacing Softmax by SVM and finetune
□ Training is expensive
□ Convolution for each region proposal, after warping
□ Object detection is slow
5. Comparision: R-CNN vs Fast R-CNN
5
■ Fast R-CNN
□ Architecture
□ single-stage training pipeline: combining
(1) Log loss
(2) Smooth L1 (= Huber loss when delta is 1)
□ Multi-task loss for each RoI
Indicator function,
u = 0 for background
6. Comparision: R-CNN vs Fast R-CNN
6
■ Fast R-CNN
□ Improvements
□ Feed whole image through ConvNet
□ RoI Pooling (no warping)
y
x
Backprop of RoI pooling
7. Comparision: R-CNN vs Fast R-CNN
7
■ Fast R-CNN
□ Limitation
□ Complete architecture depends on external
RoI proposal algorithm
□ Have to extract fixed N(=64) regions
from each image
□ Hard negative mining:
25% positive: IoU in [0.5, 1]
75% negative: IoU in [0.1, 0.5)
□ Weekly addressed multi-scale invariance
□ Brute-force (fixing image resolution)
□ Image Pyramid: expensive
main idea of the paper(same as the first talk)- review your goals- present & discuss your results- comment on your own implementation (what was available, what had to bedone, what were the difficulties)-> 1. data preprocessing(parsing json), managing two independent projects, making code work in general(since we have many variable here:FDA_mode, round, thresholding, and so on)- conclusion (e.g strengths/weaknesses of the paper, potential future work)
-> 시간 부족(학습)
-> 사실은 selfsupervised에서 multiband average가 있어야 함.ㅎ ㅏ지만 시간상 하지 못하였다. FDA에서는 사실 이부분에서 주요한 성능향상이 이루어졌기 때문에 Intra에서도 향상이 기대된다.
Explain meaning of ‘Domain adaptation’ : adapting a model trained with annotated samples from one distribution (source), to operate on a different (target) distribution for which no annotations are given
Our method does not require any training to perform the domain alignment, just a simple Fourier Transform and its inverse. Despite its simplicity, it achieves state-of-the-art performance in the current benchmarks, when integrated into a relatively standard semantic segmentation model
Many researches have been proposed for ’Domain Adaptation’
However, state-of-the-art methods are complex
Explain meaning of ‘Domain adaptation’ : adapting a model trained with annotated samples from one distribution (source), to operate on a different (target) distribution for which no annotations are given
Our method does not require any training to perform the domain alignment, just a simple Fourier Transform and its inverse. Despite its simplicity, it achieves state-of-the-art performance in the current benchmarks, when integrated into a relatively standard semantic segmentation model
Many researches have been proposed for ’Domain Adaptation’
However, state-of-the-art methods are complex