Determination of hand dimensions for hand and gesture recognition with a computing interface

A non-transitory computer-readable medium having instructions thereon that when operated on by a computer causes the computer to perform operations for recognizing hand gestures, the operations comprising:

• receiving an input sequence of frames from a camera;
• identifying frames of the sequence in which a first hand is recognized;
• identifying points in the identified frames corresponding to features of the recognized first hand;
• determining a value for each of a first set of different feature lengths of the recognized first hand using the identified points for each identified frame, wherein a different value is determined for a same feature length in different ones of the identified frames and different ones of the identified frames being used for different feature lengths when at least one of the identified frames having noise, one or more distortions or one or more occlusions obscuring one or more feature points in the recognized first hand thereby making the at least one identified frame unreliable for use in determining feature lengths of the one or more feature points that are obscured;
• collecting each different feature length value for the identified frames independently of each other feature length value, providing multiple different values for the same feature length from different frames;
• statistically analyzing each different feature length value to determine an estimate of each different feature length independently of determining each other feature length, including independently analyzing each different feature length value to determine whether the estimate of each different feature length should be generated, wherein a hand model comprises the estimated feature lengths of the first hand;
• applying the estimated feature lengths to a hand tracking system after confidence as to the accuracy of each of the estimated feature lengths is determined to reach a satisfactory level, the hand tracking system for applying commands to a computer system;
• determining when a second hand enters the input sequence;
• measuring feature lengths for the second hand using a first frame in which the second hand enters;
• comparing feature length measurements for the second hand to the feature length estimates of the first hand to determine whether the second hand matches the first hand;
• if the second hand matches the first hand, then using the corresponding prior feature length estimates from the first hand for the second hand, without refining the hand-model of the first hand;
• and
• if the second hand does not match the first hand, then refining the hand-model such that the refined hand model corresponds to estimated feature lengths of the second hand.

A non-transitory computer-readable medium having instructions thereon that when operated on by a computer causes the computer to perform operations for recognizing hand gestures, the operations comprising:

• identify frames of an input sequence of frames in which a first hand is present;
• identify points in the identified frames corresponding to features of the first hand;
• determine a value for each of a set of different feature lengths of the first hand using the identified points for each identified frame;
• collect each different feature length value for the identified frames independently of each other feature length value;
• analyze each different feature length value to determine an estimate of each different feature length of the first hand;
• apply the estimated feature lengths of the first hand to a hand tracking system;
• identify a second hand in one or more frames of the input sequence, the one or more frames occurring in the input sequence after the frames including the first hand;
• measure feature lengths of the second hand using the one or more frames;
• compare feature length measurements of the second hand to feature length estimates of the first hand;
• and
• determine whether the second hand matches the first hand, based on the comparison, and
• wherein if the second hand matches the first hand, then the feature length estimates of the first hand is used for the second hand, and
• wherein if the second hand does not match the first hand, then determine an estimate of each different feature lengths of the second hand separately from the estimation of each different feature lengths of the first hand.