How to choose right offset value in crop layer

Jiu XU

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Apr 19, 2016, 9:49:58 PM4/19/16

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Does anybody know how to select proper offset value in crop_param, like:

layer {
	name: "score"
	type: "Crop"
	bottom: "upscore"
	bottom: "data"
	top: "score"
	crop_param {
	axis: 2
	offset: 19
	}
	}

I though it is applied for keeping aspect ratio, but cannot find out how to calculate it based on input and output sizes.

Carrie Li

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Apr 26, 2016, 10:07:09 AM4/26/16

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I am new to FCN and I don't understand the crop layer, but I think you could refer to the Python script "net.py" on https://github.com/shelhamer/fcn.berkeleyvision.org .

Jiu XU

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Apr 27, 2016, 7:31:48 AM4/27/16

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Hi Li

Thanks for the reply. I've checked the script you mentioned, but still not clear about how to get offset value calculated.

在 2016年4月26日星期二 UTC+9下午11:07:09，Carrie Li写道：

Carrie Li

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May 3, 2016, 5:32:48 AM5/3/16

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You should write your own net.py according to your demand, then run it , you will get the train.prototxt and val.prototxt with the offset value in crop layer.

在 2016年4月27日星期三 UTC+8下午7:31:48，Jiu XU写道：

Jiu XU

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May 7, 2016, 6:33:53 AM5/7/16

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Thanks for the reply.

I got the value the way as you mentioned, just cursious about how to calculate the offset.