
An intuitive explanation of the SSD MultiBox object detection technique - edshiro
https://towardsdatascience.com/understanding-ssd-multibox-real-time-object-detection-in-deep-learning-495ef744fab
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edshiro
Author here! First many thanks for upvoting my post.

I only recently started delving into how object detection using deep learning
worked and was overwhelmed by the amount of prior information (including
knowledge about past papers and deep learning networks) one had to have to
understand how some of these techniques worked. So I decided to write a post
that would help build an intuitive understanding of a given object detection
technique (SSD in this case), while not spooking people with math formulas.

Would really appreciate some feedback from anyone who has read the post.

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Rapzid
Thanks for this! CNN object detection is a tough subject to crack ATM..

I've been playing with the tensorflow object detection project for work, but
the tutorials are in various states of broken right now.. The COCO models in
their zoo have pretty good results detecting much of what they know about in a
scene, however the new Open Image Dataset model only hits on a few major scene
elements and.. appears to have a footware fetish.

I'm simultaneously attempting to train a new model based on resnet101 and the
open image dataset, and taking the deep learning course by Andrew NG on
coursera trying to build a better understanding of the networks in these
models. It's rough going and posts like this are invaluable; thanks for
putting it together!

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visarga
There's also the YOLO ("you only look once") algo for object localization, a
little bit faster and with higher accuracy, comparison to SSD inside.

Demo (real time detection):
[https://pjreddie.com/darknet/yolo/](https://pjreddie.com/darknet/yolo/)

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edshiro
The original YOLO is faster (especially the "Fast YOLO" variant), but is a lot
less accurate in its detections: Fast YOLO has 52.7 mean Average Precision
@155 FPS vs SSD-300 with 74.3 mAP @59 FPS. But the new YOLO9000[1]
architecture seems to be even better than SSD! Would like to try it at some
point for sure.

[1] YOLO9000: Better, Faster, Stronger:
[https://arxiv.org/abs/1612.08242](https://arxiv.org/abs/1612.08242)

