A method for encoding and decoding digital moving picture signals which
can decode subframes appropriately in relation to time if a part of a bit
stream is missing or an error occurs in the bit stream, and can suppress
degradation of a reproduced picture if decoding of a subframe including a
picture in motion in relation to time becomes unfeasible. In the method
for encoding and decoding digital moving picture signals of this
invention, information for one frame is encoded correspondingly to a
spatial hierarchy of a frame, subframes and blocks. A subframe time
position number and a subframe space number are attached to an identifier
of each of the subframe, thereby resuming appropriate decoding of the
subframes immediately after a trouble if an error occurs. The subframe
identifiers are placed at a certain interval in the bit stream so as to
give a smaller size to a subframe including a block which is in motion
and difficult to be encoded, thereby suppressing degradation of a
reproduced picture if decoding of the subframe becomes unfeasible.