1. An image processing apparatus performing conversion processing for dividing an image stored in a memory into tiles, the image processing apparatus comprising: a first conversion unit configured to store span information in page line sequence representing an image, in the memory to perform tile sequence conversion processing for converting the span information in page line sequence into span information in tile sequence; a second conversion unit configured to store pixel information in page line sequence representing an image, in the memory to perform tile sequence conversion processing for converting the pixel information in page line sequence into pixel information in tile sequence; and a control unit configured to cause the first conversion unit to perform the tile sequence conversion processing of the first conversion unit in a case where a usage amount of the memory used in a case that the first conversion unit performs the tile sequence conversion processing on the image is equal to or less than a usage amount of the memory used in a case that the second conversion unit performs the tile sequence conversion processing on the image, and cause the second conversion unit to perform the tile sequence conversion processing of the second conversion unit in a case where the usage amount of the memory used in the case that the first conversion unit performs the tile sequence conversion processing on the image is more than the usage amount of the memory used in the case that the second conversion unit performs the tile sequence conversion processing on the image.