Actually, I have tried that earlier and this is what throws with model.executeAsync
with jpg image
Image: 1440000 bytes with shape: Tensor {
  kept: false,
  isDisposedInternal: false,
  shape: [ 1, 600, 800, 3 ],
  dtype: 'int32',
  size: 1440000,
  strides: [ 1440000, 2400, 3 ],
  dataId: {},
  id: 918,
  rankType: '4',
  scopeId: 2
}

Error: Invalid TF_Status: 3
Message: In[0] and In[1] has different ndims: [1,8,8,64,2] vs. [2,1]

With png image
Error: The shape of dict['input_tensor'] provided in model.execute(dict) must be [1,-1,-1,3], but was [1,600,800,4]