How to fix the issue of Input has undefined rank in TensorFlow?-CodePudding

I am trying to define a custom DensNet. But, I am getting a weird error and mot understand why. The code is as follows:

def densenet(input_shape, n_classes, filters = 32):
    
    #batch norm   relu   conv
    def bn_rl_conv(x,filters,kernel=1,strides=1):
        
        x = BatchNormalization()(x)
        x = ReLU()(x)
        x = Conv2D(filters, kernel, strides=strides,padding = 'same')(x)
        return x
    
    def dense_block(x, repetition):
        
        for _ in range(repetition):
            y = bn_rl_conv(x, 4*filters)
            y = bn_rl_conv(y, filters, 3)
            x = concatenate([y,x])
        return x
        
    def transition_layer(x):
        
        x = bn_rl_conv(x, K.int_shape(x)[-1] //2 )
        x = AvgPool2D(2, strides = 2, padding = 'same')(x)
        return x
    
    inp = Input (input_shape)
    x = Conv2D(64, 7, strides = 2, padding = 'same')(inp)
    x = MaxPool2D(3, strides = 2, padding = 'same')(x)
                        
    for repetition in [2,4,6,4]:
        
        d = dense_block(x, repetition)
        x = transition_layer(d)
    x = GlobalAveragePooling2D()(x)
    
    output = Dense(n_classes, activation = 'softmax')(x)
    
    model = Model(inp, output)
    return model

input_shape = (1024,2,1)
num_classes = 24
model = densenet(input_shape,num_classes)

The error is stating the following:

/usr/local/lib/python3.7/dist-packages/keras/utils/traceback_utils.py in error_handler(*args, **kwargs)
     65     except Exception as e:  # pylint: disable=broad-except
     66       filtered_tb = _process_traceback_frames(e.__traceback__)
---> 67       raise e.with_traceback(filtered_tb) from None
     68     finally:
     69       del filtered_tb

/usr/local/lib/python3.7/dist-packages/keras/layers/normalization/batch_normalization.py in build(self, input_shape)
    296     if not input_shape.ndims:
    297       raise ValueError(
--> 298           f'Input has undefined rank. Received: input_shape={input_shape}.')
    299     ndims = len(input_shape)
    300 

ValueError: Input has undefined rank. Received: input_shape=<unknown>.

Why am I getting this error? I have already indicated the input shape. How can I fix this issue?

CodePudding user response：

You are calling Input layer incorrectly. You're passing input_shape to the __call__() method instead of the shape parameter.

Change:

inp = Input (input_shape)

To:

inp = Input(shape=input_shape)