InvalidArgumentError: Incompatible shapes: [1,512,1024,3] vs. [1,512,1024,4,1]

[qiaoD]

Traceback (most recent call last):
File "main.py", line 69, in
outputSavePath="../example/output")
File "/usr/qiaodong/dwt/E2E/forward.py", line 35, in forward_model
keepProb: 1.0})
File "/usr/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 789, in run
run_metadata_ptr)
File "/usr/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 997, in _run
feed_dict_string, options, run_metadata)
File "/usr/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1132, in _do_run
target_list, options, run_metadata)
File "/usr/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1152, in _do_call
raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.InvalidArgumentError: Incompatible shapes: [1,512,1024,3] vs. [1,512,1024,4,1]
[[Node: model_builder/mul = Mul[T=DT_FLOAT, _device="/job:localhost/replica:0/task:0/cpu:0"](_arg_Placeholder_0_0, model_builder/ExpandDims)]]

Caused by op u'model_builder/mul', defined at:
File "main.py", line 69, in
outputSavePath="../example/output")
File "/usr/qiaodong/dwt/E2E/forward.py", line 19, in forward_model
model.build(tfBatchImages, tfBatchSS, tfBatchSSMask, keepProb=keepProb)
File "/usr/qiaodong/dwt/E2E/e2e_model.py", line 21, in build
inputData = inputData * ss
File "/usr/lib/python2.7/site-packages/tensorflow/python/ops/math_ops.py", line 838, in binary_op_wrapper
return func(x, y, name=name)
File "/usr/lib/python2.7/site-packages/tensorflow/python/ops/math_ops.py", line 1061, in _mul_dispatch
return gen_math_ops._mul(x, y, name=name)
File "/usr/lib/python2.7/site-packages/tensorflow/python/ops/gen_math_ops.py", line 1377, in _mul
result = _op_def_lib.apply_op("Mul", x=x, y=y, name=name)
File "/usr/lib/python2.7/site-packages/tensorflow/python/framework/op_def_library.py", line 767, in apply_op
op_def=op_def)
File "/usr/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2506, in create_op
original_op=self._default_original_op, op_def=op_def)
File "/usr/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 1269, in init
self._traceback = _extract_stack()

InvalidArgumentError (see above for traceback): Incompatible shapes: [1,512,1024,3] vs. [1,512,1024,4,1]
[[Node: model_builder/mul = Mul[T=DT_FLOAT, _device="/job:localhost/replica:0/task:0/cpu:0"](_arg_Placeholder_0_0, model_builder/ExpandDims)]]