upgrade the K : number of channel

[souzou]

Hello,

In my research I wan't to upgrade the number of channel K, for exemple to use 4 or 5 channel adding to RGB,
My question is where can I found the file that define or allow me to define a bigger number of channels?
Thx :)

[bhack]

Try to take a look here #1486

[shelhamer]

Caffe is general w.r.t. to the number of input channels K. In Caffe there's no need to explicitly define the input channel, height, or width dimensionality in the model as it is loaded from the data. Prepare the data in an LMDB or your format of choice with each feature channel included:

import numpy as np
import caffe
import lmdb

# obviously load your own inputs here -- this is just by way of example
# to show the data can have any channel dimension
# as the dimensions are N x K x H x W
inputs = np.zeros((10, 5, 227, 227))

in_db = lmdb.open('input-lmdb', map_size=int(1e12))
with in_db.begin(write=True) as in_txn:
    for in_idx, in_ in enumerate(inputs):
        in_dat = caffe.io.array_to_datum(in_)
        in_txn.put('{:0>10d}'.format(in_idx), im_dat.SerializeToString())
in_db.close()

There's no need for N-D blobs to simply increase the channel dimension K. If you had volumetric data on the other hand (a whole new axis of the data, not more dimensions of a given axis) then N-D blobs would be needed.

[ToruHironaka]

I have a question for making sure of upgrading K channel number. I could create my dataset with K channel 4 by your script or convert_imageset and I changed K channel number on deploy.prototxt but I got a trouble when I classified an image with caffe.Classifier. It caused an error: "blob.cpp:455] Check failed: ShapeEquals(proto) shape mismatch (reshape not set)". This error was understandable because I increased the number of K channel from 3 to 4 in deploy.prototxt while I was training. However, I changed K channel back to 4 from 3 in deploy.prototxt and classify an image again. The error problem was solved and I could classify with my trained model. Is this because caffe does not have to explicitly defined K channel you mentioned here?