A motion information storing method, wherein a current block consists of a first subblock and a second subblock, the first subblock and the second subblock are separated by a common boundary, wherein the common boundary is a split line of a geometric partition mode, the first subblock corresponds to first motion information and the second subblock corresponds to second motion information, wherein the first motion information comprises a uni-prediction motion vector for the first subblock, the second motion information comprises a uni-prediction motion vector for the second subblock, the method comprising: determining a distance between a sample set in the current block and the common boundary; wherein the distance is calculated by the following: distFromLine = x ≪ N + K * P 1 + y ≪ N + K * P 2 − P 3; wherein the distFromLine represents the distance, x represents a horizontal coordinate of a target position in the sample set, y represents a vertical coordinate of the target position, K is a non-negative integer, N=1, and P1, P2 and P3 are a first calculation parameter, a second calculation parameter and a third calculation parameter respectively, wherein the first calculation parameter is determined by checking a preset lookup table according to an angular parameter, the second calculation parameter is determined by checking the lookup table according to a temp angular parameter, and the third calculation parameter is determined based on the angular parameter and a distance parameter; wherein the angular parameter is represented as angleIdx, and the temp angular parameter is obtained by (angleIdx+8)%32, wherein the distance parameter is represented as distanceIdx; the angleIdx specifying an angle index of the geometric partition mode, and the distanceIdx specifying a distance index of the geometric partition mode; and comparing the distance with a threshold to determine whether to store third motion information for the sample set, wherein the third motion information is derived by combining the first motion information and the second motion information when the first motion information and the second motion information are from different reference picture lists; and the third motion information is equal to the first motion information or the second motion information when the first motion information and the second motion information are from a same reference picture list; storing the third motion information for the sample set in the event that an absolute value of the distance is smaller than the threshold; wherein the stored motion information is used for determining prediction value of the sample set, or the stored motion information is used as reference information for prediction process of future coding blocks. determining a distance between a sample set in the current block and the common boundary; wherein the distance is calculated by the following: distFromLine = x ≪ N + K * P 1 + y ≪ N + K * P 2 − P 3; wherein the distFromLine represents the distance, x represents a horizontal coordinate of a target position in the sample set, y represents a vertical coordinate of the target position, K is a non-negative integer, N=1, and P1, P2 and P3 are a first calculation parameter, a second calculation parameter and a third calculation parameter respectively, wherein the first calculation parameter is determined by checking a preset lookup table according to an angular parameter, the second calculation parameter is determined by checking the lookup table according to a temp angular parameter, and the third calculation parameter is determined based on the angular parameter and a distance parameter; wherein the angular parameter is represented as angleIdx, and the temp angular parameter is obtained by (angleIdx+8)%32, wherein the distance parameter is represented as distanceIdx; the angleIdx specifying an angle index of the geometric partition mode, and the distanceIdx specifying a distance index of the geometric partition mode; and comparing the distance with a threshold to determine whether to store third motion information for the sample set, wherein the third motion information is derived by combining the first motion information and the second motion information when the first motion information and the second motion information are from different reference picture lists; and the third motion information is equal to the first motion information or the second motion information when the first motion information and the second motion information are from a same reference picture list; storing the third motion information for the sample set in the event that an absolute value of the distance is smaller than the threshold; wherein the stored motion information is used for determining prediction value of the sample set, or the stored motion information is used as reference information for prediction process of future coding blocks.