I am trying to implement u-net in Keras,but I got this error while training the model(call model.fit()):
ValueError: Error when checking target: expected conv2d_302 to have shape > (None, 1, 128, 640) but got array with shape (360, 1, 128, 128)
And the output of the model.summary() is :
Layer (type) Output Shape Param # Connected to
==================================================================================================
input_19 (InputLayer) (None, 1, 128, 128) 0
__________________________________________________________________________________________________
conv2d_303 (Conv2D) (None, 32, 128, 128) 320 input_19[0][0]
__________________________________________________________________________________________________
conv2d_304 (Conv2D) (None, 32, 128, 128) 9248 conv2d_303[0][0]
__________________________________________________________________________________________________
max_pooling2d_83 (MaxPooling2D) (None, 32, 64, 64) 0 conv2d_304[0][0]
__________________________________________________________________________________________________
conv2d_305 (Conv2D) (None, 64, 64, 64) 18496 max_pooling2d_83[0][0]
__________________________________________________________________________________________________
conv2d_306 (Conv2D) (None, 64, 64, 64) 36928 conv2d_305[0][0]
__________________________________________________________________________________________________
max_pooling2d_84 (MaxPooling2D) (None, 64, 32, 32) 0 conv2d_306[0][0]
__________________________________________________________________________________________________
conv2d_307 (Conv2D) (None, 128, 32, 32) 73856 max_pooling2d_84[0][0]
__________________________________________________________________________________________________
conv2d_308 (Conv2D) (None, 128, 32, 32) 147584 conv2d_307[0][0]
__________________________________________________________________________________________________
max_pooling2d_85 (MaxPooling2D) (None, 128, 16, 16) 0 conv2d_308[0][0]
__________________________________________________________________________________________________
conv2d_309 (Conv2D) (None, 256, 16, 16) 295168 max_pooling2d_85[0][0]
__________________________________________________________________________________________________
conv2d_310 (Conv2D) (None, 256, 16, 16) 590080 conv2d_309[0][0]
__________________________________________________________________________________________________
max_pooling2d_86 (MaxPooling2D) (None, 256, 8, 8) 0 conv2d_310[0][0]
__________________________________________________________________________________________________
conv2d_311 (Conv2D) (None, 512, 8, 8) 1180160 max_pooling2d_86[0][0]
__________________________________________________________________________________________________
conv2d_312 (Conv2D) (None, 512, 8, 8) 2359808 conv2d_311[0][0]
__________________________________________________________________________________________________
conv2d_transpose_29 (Conv2DTran (None, 256, 16, 16) 524544 conv2d_312[0][0]
__________________________________________________________________________________________________
concatenate_29 (Concatenate) (None, 256, 16, 32) 0 conv2d_transpose_29[0][0]
conv2d_310[0][0]
__________________________________________________________________________________________________
conv2d_313 (Conv2D) (None, 256, 16, 32) 590080 concatenate_29[0][0]
__________________________________________________________________________________________________
conv2d_314 (Conv2D) (None, 256, 16, 32) 590080 conv2d_313[0][0]
__________________________________________________________________________________________________
conv2d_transpose_30 (Conv2DTran (None, 128, 32, 64) 131200 conv2d_314[0][0]
__________________________________________________________________________________________________
concatenate_30 (Concatenate) (None, 128, 32, 96) 0 conv2d_transpose_30[0][0]
conv2d_308[0][0]
__________________________________________________________________________________________________
conv2d_315 (Conv2D) (None, 128, 32, 96) 147584 concatenate_30[0][0]
__________________________________________________________________________________________________
conv2d_316 (Conv2D) (None, 128, 32, 96) 147584 conv2d_315[0][0]
__________________________________________________________________________________________________
conv2d_transpose_31 (Conv2DTran (None, 64, 64, 192) 32832 conv2d_316[0][0]
__________________________________________________________________________________________________
concatenate_31 (Concatenate) (None, 64, 64, 256) 0 conv2d_transpose_31[0][0]
conv2d_306[0][0]
__________________________________________________________________________________________________
conv2d_317 (Conv2D) (None, 64, 64, 256) 36928 concatenate_31[0][0]
__________________________________________________________________________________________________
conv2d_318 (Conv2D) (None, 64, 64, 256) 36928 conv2d_317[0][0]
__________________________________________________________________________________________________
conv2d_transpose_32 (Conv2DTran (None, 32, 128, 512) 8224 conv2d_318[0][0]
__________________________________________________________________________________________________
concatenate_32 (Concatenate) (None, 32, 128, 640) 0 conv2d_transpose_32[0][0]
conv2d_304[0][0]
__________________________________________________________________________________________________
conv2d_319 (Conv2D) (None, 32, 128, 640) 9248 concatenate_32[0][0]
__________________________________________________________________________________________________
conv9 (Conv2D) (None, 32, 128, 640) 9248 conv2d_319[0][0]
__________________________________________________________________________________________________
conv2d_320 (Conv2D) (None, 1, 128, 640) 33 conv9[0][0]
==================================================================================================
Total params: 6,976,161
Trainable params: 6,976,161
Non-trainable params: 0
Here is the model code:
img_rows=128
img_cols= 128
inputs = Input((1, img_rows, img_cols))
conv1 = Conv2D(32, (3, 3), activation='relu', padding='same')(inputs)
conv1 = Conv2D(32, (3, 3), activation='relu', padding='same')(conv1)
pool1 = MaxPooling2D(pool_size=(2, 2))(conv1)
conv2 = Conv2D(64, (3, 3), activation='relu', padding='same')(pool1)
conv2 = Conv2D(64, (3, 3), activation='relu', padding='same')(conv2)
pool2 = MaxPooling2D(pool_size=(2, 2))(conv2)
conv3 = Conv2D(128, (3, 3), activation='relu', padding='same')(pool2)
conv3 = Conv2D(128, (3, 3), activation='relu', padding='same')(conv3)
pool3 = MaxPooling2D(pool_size=(2, 2))(conv3)
conv4 = Conv2D(256, (3, 3), activation='relu', padding='same')(pool3)
conv4 = Conv2D(256, (3, 3), activation='relu', padding='same')(conv4)
pool4 = MaxPooling2D(pool_size=(2, 2))(conv4)
conv5 = Conv2D(512, (3, 3), activation='relu', padding='same')(pool4)
conv5 = Conv2D(512, (3, 3), activation='relu', padding='same')(conv5)
up6 = concatenate([Conv2DTranspose(256, (2, 2), strides=(2, 2), padding='same')(conv5), conv4], axis=3)
conv6 = Conv2D(256, (3, 3), activation='relu', padding='same')(up6)
conv6 = Conv2D(256, (3, 3), activation='relu', padding='same')(conv6)
up7 = concatenate([Conv2DTranspose(128, (2, 2), strides=(2, 2), padding='same')(conv6), conv3], axis=3)
conv7 = Conv2D(128, (3, 3), activation='relu', padding='same')(up7)
conv7 = Conv2D(128, (3, 3), activation='relu', padding='same')(conv7)
up8 = concatenate([Conv2DTranspose(64, (2, 2), strides=(2, 2), padding='same')(conv7), conv2], axis=3)
conv8 = Conv2D(64, (3, 3), activation='relu', padding='same')(up8)
conv8 = Conv2D(64, (3, 3), activation='relu', padding='same')(conv8)
up9 = concatenate([Conv2DTranspose(32, (2, 2), strides=(2, 2), padding='same')(conv8), conv1], axis=3)
conv9 = Conv2D(32, (3, 3), activation='relu', padding='same')(up9)
conv9 = Conv2D(32, (3, 3), activation='relu', padding='same', name='conv9')(conv9)
conv10 = Conv2D(1, (1, 1), activation='sigmoid')(conv9)
model = Model(inputs=[inputs], outputs=[conv10])
model.compile(optimizer=Adam(lr=1e-5), loss="mean_absolute_error")
model.summary()
model.fit(X_train, y_train, batch_size=36, nb_epoch=5)
I don't understand why the output of the second last layer(conv9) is different from the expectation of the last layer(conv10).
The Keras model is a courtesy of https://github.com/jocicmarko/ultrasound-nerve-segmentation/blob/master/train.py .
Updated: Added the complete model.summary().
It is most certain that the author of the original wanted to concatenate on the channels dimension, not one of the image dimensions.
The tensors in convolutional networks could be in one of the two formats:
(batch_size, width, height, channels)
or
(batch_size, channels, width, height)
In the model you linked the first format was used, but your model uses the second format.
You can fix it in one of the two ways:
axis=3 in the concatente layers to axis=1or
data_format="channels_last" in the convolutional layers. The default value of data_format, if omitted, is taken from a keras config, and most likely this value was different for you and for the author of the model you used. See https://keras.io/layers/convolutional/#conv2dUPDATE: as a matter of fact, the original model changes the data_format at the very beginning of the file you linked to:
K.set_image_data_format('channels_last')
Just add this line at the beginning of your model, and it will solve the issue.