运行:i1=imread('1.bmp') 这句运行正常 i2=histeq(i1) 后出现以下??? Error using ==> e:/matlab/toolbox/images/images/private/checkinput (check_attributes)Function imhist expected its first input argument, I or X,to be two-dimensional.Error in ==> E:\MATLAB\toolbox\images\images\private\checkinput.mOn line 37 ==> check_attributes(A, attributes, function_name, variable_name, ...Error in ==> E:\MATLAB\toolbox\images\images\imhist.m (parse_inputs)On line 173 ==> checkinput(a, 'double uint8 logical uint16', '2d', mfilename, 'I or X', 1);Error in ==> E:\MATLAB\toolbox\images\images\imhist.mOn line 49 ==> [a, n, isScaled, top, map] = parse_inputs(varargin{:});Error in ==> E:\MATLAB\toolbox\images\images\histeq.mOn line 131 ==> nn = imhist(a,n)';