
Faster R-CNN: Down the rabbit hole of modern object detection - vierja
https://tryolabs.com/blog/2018/01/18/faster-r-cnn-down-the-rabbit-hole-of-modern-object-detection/
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rambossa
Does anyone try to get accurate bounding boxes (rotation, correct angle) with
these object detection models? Or does the greatly harden the problem?

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electrograv
That’s exactly what Faster-RCNN does. Edit: Except for rotation — they are
axis aligned bounding boxes.

Mask-RCNN (more recent) takes it a step further and also generates a per-
object pixel segmentation mask, which is even better than a bounding box
obviously. For that reason, Mask-RCNN is much more exciting to me, and
incredibly impressive if you see examples showing what it can do.

That said, “under the hood” of Mask-RCNN are still axis aligned 2D bounding
boxes for every object (and this occasionally creates artifacts when a box is
erroneously too small and crops off part of an object). IMO we need to somehow
get away from these AABBs, but right now methods that use them simply work the
best.

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nicodjimenez
Object detection is an interesting failure for deep learning. Systems such as
these perform well but whenever you have something like non max suppression at
the end you are bound to get hard to fix errors. I'm more optimistic about
deep mask and similar pixel wise approaches as well as using RNNs to generate
a list of objects from an image.

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swframe2
I saw this today:
[https://github.com/facebookresearch/Detectron](https://github.com/facebookresearch/Detectron)

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nnq
wansn't R-CNN already superseded by YOLO[1]? didn't read the article, but no
mention of it to compare itself to, so seems outdated maybe.

anyone had the time to dig deeper into this?

[1]
[https://pjreddie.com/media/files/papers/yolo.pdf](https://pjreddie.com/media/files/papers/yolo.pdf)

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eggie5
Tradeoffs: RCNN has better accuracy. YOLO is faster.

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pilooch
rcnn is two steps and ssd is single step.

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BillyParadise
Is this what they use for self driving cars?

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bitL
Faster R-CNN gives you only like 5fps on high-end GPU, so answer is no.

