The invention discloses a
pressure vessel air tightness detection method based on connected domain determination. The method comprises the following steps of step1, setting the original pressure valueof a
pressure vessel to be P0, setting the pressure value after T time to be P1, and when P0-P1< / =
delta, setting the
delta as a
pressure difference threshold, which expresses a unpressurized state; when P0-P1>
delta, expressing that the pressure is being applied and an
air tightness test begins; step2, taking the N frames of the images of a video after the
air tightness test is started, wherein the n equals to t*f, the t is test time and the f is a video
frame rate; and taking the N frames of the images as I1, I2,..., In, graying Ii and acquiring a corresponding grey-
scale map Gi, wherein thei equals to 1, 2,...,n; and step3, considering the continuity of bubbles, calculating the number Q of connected images Fj in which the number of connected domains wj is greater than k in the n framesof the connected images Fj, if the Q is greater than a threshold T, considering that there is an air leakage condition. The method has an
advantage that based on the connected domain determination, through combining the sizes and the number of the bubbles, and a dynamic characteristic, whether a
pressure vessel has the air leakage condition can be accurately determined.