A method of operation of an image processing system comprising: receiving an image sequence having received images each having a lens position; forming image pairs having a first image and a second image, such that the image pairs of the received images are in consecutive order for the lens position; partitioning the received images into a grid array having grid blocks; calculating an iteration number for the blur difference between a grid block having a position in the first image and a corresponding grid block having the same position in the second image in each of the image pairs of the image sequence, the iteration number being calculated by iteratively convoluting one of the grid blocks with a blur kernel until the blur metrics of the grid blocks are within a blur difference threshold, the magnitude of the iteration number indicating a number of convolutions performed and the sign of the iteration number indicating which of the grid blocks of the first and second images is sharper; calculating an iteration depth map having an iteration depth for each set of the corresponding grid blocks of the received images by either calculating a zero-crossing point of a curve of the iteration numbers for the set of corresponding grid blocks of the image sequence or determining that no zero-crossing point exists for the set of the corresponding grid blocks, the iteration depth representing a distance represented by a lens position corresponding to the zero-crossing point; calculating a median depth map having a median depth for each of the grid blocks by applying a median filter to the iteration depth map; calculating a depth difference map by subtracting the median depth map from the iteration depth map; calculating a variance depth map having a block variance for each of the grid blocks of the received images; calculating an image depth map having an element depth assigned to each of the grid blocks, the element depth based on the iteration depth map, the median depth map, the depth difference map, and the variance depth map; and calculating a display image based on the received images and the image depth map for displaying on a display device. receiving an image sequence having received images each having a lens position; forming image pairs having a first image and a second image, such that the image pairs of the received images are in consecutive order for the lens position; partitioning the received images into a grid array having grid blocks; calculating an iteration number for the blur difference between a grid block having a position in the first image and a corresponding grid block having the same position in the second image in each of the image pairs of the image sequence, the iteration number being calculated by iteratively convoluting one of the grid blocks with a blur kernel until the blur metrics of the grid blocks are within a blur difference threshold, the magnitude of the iteration number indicating a number of convolutions performed and the sign of the iteration number indicating which of the grid blocks of the first and second images is sharper; calculating an iteration depth map having an iteration depth for each set of the corresponding grid blocks of the received images by either calculating a zero-crossing point of a curve of the iteration numbers for the set of corresponding grid blocks of the image sequence or determining that no zero-crossing point exists for the set of the corresponding grid blocks, the iteration depth representing a distance represented by a lens position corresponding to the zero-crossing point; calculating a median depth map having a median depth for each of the grid blocks by applying a median filter to the iteration depth map; calculating a depth difference map by subtracting the median depth map from the iteration depth map; calculating a variance depth map having a block variance for each of the grid blocks of the received images; calculating an image depth map having an element depth assigned to each of the grid blocks, the element depth based on the iteration depth map, the median depth map, the depth difference map, and the variance depth map; and calculating a display image based on the received images and the image depth map for displaying on a display device.