Method for encoding and decoding image based on entry point in bitstream and apparatus using same

A video decoding method, performed by a decoding apparatus, comprising:

• receiving entry point information specifying an entry point for decoding of at least one substream for a picture;
• and
• decoding at least one substreams based on the entry point information,
• wherein the entry point information include a number syntax element representing a number of offset syntax elements in a slice header,
• wherein the entry point information includes an offset syntax element representing the entry point of the substream when the number of the offset syntax elements is larger than 0,
• wherein the offset syntax element represents a number of bytes between two entry points,
• wherein the entry point information includes a length syntax element specifying a bits length of the offset syntax element when the number of the offset syntax elements is larger than 0,
• wherein a value of the number syntax element and a value of the length syntax element are decoded based on ue(v) descriptor and a value of the offset syntax element is decoded based on u(v) descriptor, and
• wherein the value of the length syntax element plus one corresponds to the bits length of the offset syntax element, and
• wherein the value of the number syntax element corresponds to the number of offset syntax elements in the slice header.

An image decoding apparatus, comprising:

• a decoder configured to receive entry point information specifying an entry point for decoding of at least one substream for a picture, and to decode the at least one substream based on the entry point information,
• wherein the entry point information include a number syntax element representing a number of offset syntax elements in a slice header,
• wherein the entry point information includes an offset syntax element representing the entry point of the substream when the number of the offset syntax elements is larger than 0,
• wherein the offset syntax element represents a number of bytes between two entry points,
• wherein the entry point information includes a length syntax element specifying a bits length of the offset syntax element when the number of the offset syntax elements is larger than 0,
• wherein a value of the number syntax element and a value of the length syntax element are decoded based on ue(v) descriptor and a value of the offset syntax element is decoded based on u(v) descriptor, and
• wherein the value of the length syntax element plus one corresponds to the bits length of the offset syntax element, and
• wherein the value of the number syntax element corresponds to the number of offset syntax elements in the slice header.