ValueError：层顺序需要 1 个输入，但它收到 250 个输入张量

如何解决ValueError：层顺序需要 1 个输入，但它收到 250 个输入张量

我尝试开发一个 CNN 模型来从静脉图像中提取特征，但我无法解决显示的 ValueError。

model = Sequential()
model.add(Conv2D(64,kernel_size=(2,2),activation='relu',padding='same',input_shape=(48,64,3)))
model.add(Conv2D(64,(2,padding='same'))
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(Dropout(0.25))
model.add(Flatten())
model.add(Dense(64,activation='relu'))
model.add(Dropout(0.5))
model.add(Dense(5,activation='softmax'))
model.summary()

model.compile(loss=keras.losses.categorical_crossentropy,optimizer=keras.optimizers.Adadelta(),metrics=['accuracy'])

datagen.fit(x_train)

model.fit(datagen.flow(x_train,y_train,batch_size=3),steps_per_epoch=len(x_train)/3,epochs=12,verbose=1)
score = model.evaluate(x_test,y_test,verbose=0)
print('Test loss:',score[0])
print('Test accuracy:',score[1])

错误跟踪如下：

    ValueError                                Traceback (most recent call last)
<ipython-input-14-b07132f37f80> in <module>
     12 datagen.fit(x_train)
     13 
---> 14 model.fit(datagen.flow(x_train,verbose=1)
     15 score = model.evaluate(x_test,verbose=0)
     16 print('Test loss:',score[0])

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py in _method_wrapper(self,*args,**kwargs)
    106   def _method_wrapper(self,**kwargs):
    107     if not self._in_multi_worker_mode():  # pylint: disable=protected-access
--> 108       return method(self,**kwargs)
    109 
    110     # Running inside `run_distribute_coordinator` already.

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py in fit(self,x,y,batch_size,epochs,verbose,callbacks,validation_split,validation_data,shuffle,class_weight,sample_weight,initial_epoch,steps_per_epoch,validation_steps,validation_batch_size,validation_freq,max_queue_size,workers,use_multiprocessing)
   1096                 batch_size=batch_size):
   1097               callbacks.on_train_batch_begin(step)
-> 1098               tmp_logs = train_function(iterator)
   1099               if data_handler.should_sync:
   1100                 context.async_wait()

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\def_function.py in __call__(self,**kwds)
    778       else:
    779         compiler = "nonXla"
--> 780         result = self._call(*args,**kwds)
    781 
    782       new_tracing_count = self._get_tracing_count()

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\def_function.py in _call(self,**kwds)
    821       # This is the first call of __call__,so we have to initialize.
    822       initializers = []
--> 823       self._initialize(args,kwds,add_initializers_to=initializers)
    824     finally:
    825       # At this point we kNow that the initialization is complete (or less

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\def_function.py in _initialize(self,args,add_initializers_to)
    694     self._graph_deleter = FunctionDeleter(self._lifted_initializer_graph)
    695     self._concrete_stateful_fn = (
--> 696         self._stateful_fn._get_concrete_function_internal_garbage_collected(  # pylint: disable=protected-access
    697             *args,**kwds))
    698 

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\function.py in _get_concrete_function_internal_garbage_collected(self,**kwargs)
   2853       args,kwargs = None,None
   2854     with self._lock:
-> 2855       graph_function,_,_ = self._maybe_define_function(args,kwargs)
   2856     return graph_function
   2857 

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\function.py in _maybe_define_function(self,kwargs)
   3211 
   3212       self._function_cache.missed.add(call_context_key)
-> 3213       graph_function = self._create_graph_function(args,kwargs)
   3214       self._function_cache.primary[cache_key] = graph_function
   3215       return graph_function,kwargs

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\function.py in _create_graph_function(self,kwargs,override_flat_arg_shapes)
   3063     arg_names = base_arg_names + missing_arg_names
   3064     graph_function = ConcreteFunction(
-> 3065         func_graph_module.func_graph_from_py_func(
   3066             self._name,3067             self._python_function,~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\func_graph.py in func_graph_from_py_func(name,python_func,signature,func_graph,autograph,autograph_options,add_control_dependencies,arg_names,op_return_value,collections,capture_by_value,override_flat_arg_shapes)
    984         _,original_func = tf_decorator.unwrap(python_func)
    985 
--> 986       func_outputs = python_func(*func_args,**func_kwargs)
    987 
    988       # invariant: `func_outputs` contains only Tensors,CompositeTensors,~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\eager\def_function.py in wrapped_fn(*args,**kwds)
    598         # __wrapped__ allows AutoGraph to swap in a converted function. We give
    599         # the function a weak reference to itself to avoid a reference cycle.
--> 600         return weak_wrapped_fn().__wrapped__(*args,**kwds)
    601     weak_wrapped_fn = weakref.ref(wrapped_fn)
    602 

~\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\func_graph.py in wrapper(*args,**kwargs)
    971           except Exception as e:  # pylint:disable=broad-except
    972             if hasattr(e,"ag_error_Metadata"):
--> 973               raise e.ag_error_Metadata.to_exception(e)
    974             else:
    975               raise

ValueError: in user code:

    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py:806 train_function  *
        return step_function(self,iterator)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py:796 step_function  **
        outputs = model.distribute_strategy.run(run_step,args=(data,))
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\distribute\distribute_lib.py:1211 run
        return self._extended.call_for_each_replica(fn,args=args,kwargs=kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\distribute\distribute_lib.py:2585 call_for_each_replica
        return self._call_for_each_replica(fn,kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\distribute\distribute_lib.py:2945 _call_for_each_replica
        return fn(*args,**kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py:789 run_step  **
        outputs = model.train_step(data)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py:748 train_step
        loss = self.compiled_loss(
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\compile_utils.py:204 __call__
        loss_value = loss_obj(y_t,y_p,sample_weight=sw)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\losses.py:149 __call__
        losses = ag_call(y_true,y_pred)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\losses.py:253 call  **
        return ag_fn(y_true,y_pred,**self._fn_kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\util\dispatch.py:201 wrapper
        return target(*args,**kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\losses.py:1535 categorical_crossentropy
        return K.categorical_crossentropy(y_true,from_logits=from_logits)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\util\dispatch.py:201 wrapper
        return target(*args,**kwargs)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\backend.py:4687 categorical_crossentropy
        target.shape.assert_is_compatible_with(output.shape)
    C:\Users\Asus\anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\tensor_shape.py:1134 assert_is_compatible_with
        raise ValueError("Shapes %s and %s are incompatible" % (self,other))

    ValueError: Shapes (None,None,None) and (None,5) are incompatible

    

解决方法

我可以从您的代码中看到的一个问题，在这里：

model.add(Dense(8,activation='sigmoid'))
model.compile(loss=keras.losses.categorical_crossentropy,

如果您使用损失函数 softmax，您应该使用激活 categorical cross entropy。或者，如果激活需要 binary_cross_entropy

，请使用 sigmoid