
Why CNN papers use 224x224 images? - rdabane
Why most of CNN papers use 224x224 or 223x223 size images? Why not use more standard like 640x480?
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BenFielding
According to the Alexnet paper (The first real Imagenet CNN success story -
[http://www.cs.toronto.edu/~fritz/absps/imagenet.pdf](http://www.cs.toronto.edu/~fritz/absps/imagenet.pdf)),
the choice of 224x224 (but actually 227 - there's been some confusion with the
paper I believe) was due to their use of data augmentation techniques
(translations and reflections) on the 256x256 images. The sizes of Imagenet
images varies but I believe it is common to crop to a minimum of 256x256 for
the size/minimal overall information lost tradeoff.

Section 3.5 and 4.1 of the above paper have more information.

edit: So I guess really it's down to:

1\. The fact that square images are much easier to work with

2\. The images are cropped to 256x256 because it's a convenient average size
for imagenet

3\. The 224/227 sizes are used to allow for the extraction of random patches
for translation invariance

