A method of scalable video coding for varying spatial scalability of bitstream in real time and a codec using the same

The invention encoding to be able to real-time changes in the space resolution as to change the spatial resolution in real time by using this, and further a signaling message indicating that the spatial resolution will turn extracts the bit stream and actively spatial resolution without further information of the to provide a codec using the coding method to identify a change whether or not to decode the bit stream changes the spatial resolution in real time and a method thereof. This time, if there is restriction on the network with an environment that varies the video in coding and decoding in real time or in part, change the spatial resolution at the decoder stage it is necessary to consume video, cope with the change of the spatial resolution of the video and it may provide a way to watch efficiently. Spatial resolution, scalability, extractor, space scalability