How does graph_def store the shape info of input and output of a node
each node in the graph_def doesn't contains the shape of output tensor, after importing graph_def into memory (with tf.import_graph_def), the shape of each tensor in the graph is automatically determined
I downloaded the inception v3 model(a frozen graph) from website and imported it into a session then I found that the shape of inputs and outputs of all nodes in this graph_def are already fully known, but when I freeze my own graph contaning tf.Examples queues as inputs, the batch_size info seems to be lost and replaced with a ?, my question is how I can fix or change the unknown shape when I try to freeze a graph? 
edit:
the node.attr of some nodes in graph_def contains the shape info but why not all nodes?