Error in alexnet first conv layer 11x11x96

any body can bring a reson for following

Invalid network.

Caused by:

Layer 'conv1': Input size mismatch. Size of input to this layer is different from the

expected input size.

Inputs to this layer:

from layer 'input' (28×28×1 output)

Im sure we oroperly change my image to 227 227 3

Answer 1

[Walter Roberson]

You might want to use https://www.mathworks.com/help/deeplearning/ref/augmentedimagedatastore.html specifying the output size and the ColorProcessing option (in case the input is grayscale, it can be converted to RGB automatically.)