
High-Resolution 3D Human Digitization - hliyan
https://shunsukesaito.github.io/PIFu/
======
sdan
I've tried many of these papers, and they don't work outside their datasets.

Suppose you tried this on your own camera or maybe in a different lighting: it
would totally break this.

Paper definitely seems like an improvement, but I guess no one should get
excited to use this in experimentation/production.

~~~
Jarred
I've tried a number of ML projects like this too, and sometimes they do work –
Bodypix is one example (though not precisely the same thing).

That being said, its usually pretty difficult to get code from papers to
build/run successfully due to dependencies (e.g. depending on a specific
version of Python and OpenCV 2 and requiring CUDA support)

~~~
yboris
Could anyone explain why version numbers make ML stuff so brittle? Why is the
CUDA version supposed to match? Why would a newer version of python (3.7 vs
3.6) would ever break anything?

TensorFlow is a crapshoot as far as I understand, constantly changing making
newer versions incompatible; but why do other libraries break backwards
compatibility without a major version bump?

~~~
aprdm
Because software is hard.

You might be relying on a function that only exists in 3.7 and not in 3.6,
code written in 3.6 would work but new code using 3.7 features won’t be
backwards compatible. With compiled code the errors are usually very hard for
“more used to scripts“ people to decode. You get stuff like missing symbols in
the linker phase.

ML projects usually have a lot of libraries so you also get in the transient
dependencies breaking quite often...

~~~
ryukafalz
Yeah, managing dependencies is tricky. I've been super excited about Nix and
Guix lately for that reason; if you have a single Nix/Guix revision and a list
of packages, you have all the information you need to build exactly the same
package tree. (With bit-for-bit reproducibility where possible, no less!)

Some language-specific package managers can do similar things, but you really
only get reproducibility for the whole system with a general-purpose package
manager. Poetry gets you pretty far within the Python ecosystem, but if you
need a specific version of Python/specific native libraries/etc... it doesn't
get you all the way there.

------
belval
CVPR 2020 (starting today!) has a lot of papers on the topic for interested
people.

Here is PiFuHD:
[https://arxiv.org/abs/2004.00452](https://arxiv.org/abs/2004.00452)

------
ilaksh
The next thing might be mapping from that static 3D model to some kind of
rigged model that can be animated. Then you would not only need to place the
bones and joints but also separate the clothing from the body. Extremely hard
but DL has been able to pull off some incredible stuff.

------
geeIncredible
Wow. It's such "high resolution" that the distorted triangular polygons of the
untextured models are clearly distinguishable and painfully obvious on my
phone.

I guess my idea of "high resolution" differs from what the rest of the world
describes as such.

------
saeranv
It's interesting how the legs are often an unequal length in the
reconstruction when the person is walking, due to some incorrect
interpretation of the camera perspective.

I would have guessed this wouldn't be a problem given that there are multiple
photos of the same view, such that you can resolve the depth ambiguity from a
single camera. I.e use feature detection to identify feet in > 1 views, and
then use the two images to resolve the depth of the epipolar lines that lie on
the optical axis and reconstruct the shoe in 3D space.

------
zuhayeer
Straight up en route to Ready Player One. Guess this remote thing is happening
for real for real

~~~
sansnomme
More like increased competition and computer generated avatars in the modeling
and Instagram influencing industry.

------
sungam
I am interested in high resolution 3D mapping of skin surface e.g. for facial
scar revision etc - what is the best technology available for this either
research or commercial?

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hawflakes
Pardon me for asking, but isn’t the name of the technique a sort of pun? 皮肤
means “skin” in Chinese and romanized as “pifu”

------
heinrichf
The last author and his company were/are involved in scandals about faking
results on a large scale:

[https://www.reddit.com/r/MachineLearning/comments/8zm4kl/d_l...](https://www.reddit.com/r/MachineLearning/comments/8zm4kl/d_lawsuit_alleges_fabricated_results_at_pinscreen/)

[http://sadeghi.com/dr-iman-sadeghi-v-pinscreen-inc-et-
al/](http://sadeghi.com/dr-iman-sadeghi-v-pinscreen-inc-et-al/)

~~~
hliyan
Thanks, I think this deserves an HN post of its own. Some of the things that
were done to entice Sadeghi to join sends shivers down my spine.

Edit: I've been looking at the details on the rear view of some of the
"Single-View Reconstruction" examples, and I'm starting to worry that this may
actually not be reproducible.

