Camera Calibration

An apparatus for camera calibration, comprising:

• a processor;
• and
• a memory coupled to the processor, the memory configured to store instructions which when executed by the processor become operational with the processor to:
• determine a first feature point set of a first original image captured by a first camera and a second feature point set of a second original image captured by a second camera, wherein the first feature point set corresponds to the second feature point set;
• determine, based on first external parameter values used by the first camera, a first mapping point set by mapping the first feature point set to a reference mapping plane;
• determine, based on M predetermined adjustment modes, M groups of intermediate external parameter values by adjusting second external parameter values used by the second camera, wherein M is an integer greater than or equal to 2, and each of the M predetermined adjustment modes comprises a predetermined step length;
• determine, for each adjustment mode of the M predetermined adjustment modes, a second mapping point set corresponding to the adjustment mode by mapping the second feature point set to the reference mapping plane based on a group of intermediate external parameter values, wherein the group of intermediate external parameter values is one of the M groups of intermediate external parameter values and is determined based on the adjustment mode;
• determine a distance between the first mapping point set and the second mapping point set as a distance corresponding to the adjustment mode;
• adjust, based on the distance and the predetermined step length, the second external parameter values;
• complete calibration of the second external parameter values based on a determination that distances corresponding to the respective M predetermined adjustment modes meet an iteration termination condition;
• and
• return to determine the M groups of intermediate external parameter values based on a determination that the distances corresponding to the respective M predetermined adjustment modes do not meet the iteration termination condition.

An electronic apparatus, comprising:

• a first determination module, configured to determine a first feature point set of a first original image captured by a first camera and a second feature point set of a second original image captured by a second camera, wherein the first feature point set corresponds to the second feature point set;
• a first mapping module, configured to determine, based on first external parameter values used by the first camera, a first mapping point set by mapping the first feature point set to a reference mapping plane;
• a parameter adjustment module, configured to determine, based on M predetermined adjustment modes, M groups of intermediate external parameter values by adjusting second external parameter values used by the second camera, wherein M is an integer greater than or equal to 2, and each of the M predetermined adjustment modes comprises a predetermined step length;
• a second mapping module, configured to determine, for each adjustment mode of the M predetermined adjustment modes, a second mapping point set corresponding to the adjustment mode by mapping the second feature point set to the reference mapping plane based on a group of intermediate external parameter values, wherein the group of intermediate external parameter values is one of the M groups of intermediate external parameter values and is determined based on the adjustment mode;
• a first computation module, configured to determine a distance between the first mapping point set and the second mapping point set as a distance corresponding to the adjustment mode;
• and
• an external parameter-calibration module, configured to:
• adjust, based on the distance and the predetermined step length, the second external parameter values;
• complete calibration of the second external parameter values based on a determination that distances corresponding to the respective M predetermined adjustment modes meet an iteration termination condition;
• and
• iterate, by the parameter adjustment module, to determine the M groups of intermediate external parameter values based on a determination that the distances corresponding to the respective M predetermined adjustment modes do not meet the iteration termination condition.