我使用imshow
在Matlab中打开了一个图像,我希望用新颜色(150,57,80)替换每个像素的颜色(140,50,61)。如果有人可以请告诉我如何做到这一点。
答案 0 :(得分:2)
假设A
是输入图像数据,这可能是一种方法 -
%// Initialize vectors for old and new pixels tuplets
oldval = [140,50,61]
newval = [150,57,80]
%// Reshape the input array to a 2D array, so that each column would
%// reprsent one pixel color information.
B = reshape(permute(A,[3 1 2]),3,[])
%// Find out which columns match up with the oldval [3x1] values
matches = all(bsxfun(@eq,B,oldval(:)),1)
%// OR matches = matches = ismember(B',oldval(:)','rows')
%// Replace all those columns with the replicated versions of oldval
B(:,matches) = repmat(newval(:),1,sum(matches))
%// Reshape the 2D array back to the same size as input array
out = reshape(permute(B,[3 2 1]),size(A))
示例运行 -
>> A
A(:,:,1) =
140 140 140
40 140 140
A(:,:,2) =
50 20 50
50 50 50
A(:,:,3) =
61 65 61
61 61 61
>> out
out(:,:,1) =
150 140 150
40 150 150
out(:,:,2) =
57 20 57
50 57 57
out(:,:,3) =
80 65 80
61 80 80
答案 1 :(得分:1)
bsxfun
是我解决它的方式。但是,如果您不熟悉它,则可以从图像中提取每个通道,为每个通道使用三个逻辑掩码,并使用logical
AND将它们组合在一起。执行AND将在图像中找到那些寻找特定RGB三元组的像素。
因此,我们相应地设置每个通道的输出并重建图像以产生输出。
因此,根据输入图像A
,可以执行以下操作:
red = A(:,:,1); green = A(:,:,2); blue = A(:,:,3);
mred = red == 140; mgreen = green == 50; mblue = blue == 61;
final_mask = mred & mgreen & mblue;
red(final_mask) = 150; green(final_mask) = 57; blue(final_mask) = 80;
out = cat(3, red, green, blue);