MATLAB中printpreview无法按指定尺寸显示打印图像的问题求助

我需要在Letter纸张（27.94cm×21.59cm）上打印一幅宽25.4cm、高21.2cm的图像（对应212×254的二维数组，要求每个元素占1mm空间）。使用printpreview预览时，Layout和Paper设置显示符合要求，但实际图像尺寸远未达到预期（本该占纸张约90%空间）。尝试过设置figure尺寸大于纸张、硬编码figure尺寸都无效，现有代码如下：

clear
clc
close all

x = 27.94;
y = 21.59;
xmarg = (27.94 - 25.4)/2;  
ymarg = (21.59 - 21.2)/2;
xsize = 25.4;
ysize = 21.2;

metaData = niftiinfo('index_image.nii');
vol = niftiread(metaData);

[volProc] = preProcessBrainCANDIData(vol, metaData, true);

[saggital, coronal, transverse] = size(volProc);
slice = volProc(:, :, transverse / 2);

sliceViewer(vol)

bfig = figure;
imagesc(slice)
axis off;
colormap(gray) 

clim([0, 255]);

set(bfig, 'Units','centimeters', 'Position',[0 0 xsize ysize])
movegui(bfig, 'center')

set(bfig, 'PaperUnits', 'centimeters');
set(bfig, 'PaperPosition',[xmarg ymarg xsize ysize])
set(bfig, 'PaperOrientation', 'landscape');

printpreview

核心问题是仅设置figure打印参数不够，还需让图像所在的axes完全填满打印区域，同时关闭Matlab默认的图像缩放适配。按以下逻辑修改：

• 强制axes尺寸与目标打印尺寸完全匹配，消除内边距
• 关闭自动缩放，确保每个像素对应指定物理尺寸

修改后的完整代码：

clear
clc
close all

x = 27.94;
y = 21.59;
xmarg = (27.94 - 25.4)/2;  
ymarg = (21.59 - 21.2)/2;
xsize = 25.4;
ysize = 21.2;

metaData = niftiinfo('index_image.nii');
vol = niftiread(metaData);

[volProc] = preProcessBrainCANDIData(vol, metaData, true);

[saggital, coronal, transverse] = size(volProc);
slice = volProc(:, :, transverse / 2);

sliceViewer(vol)

bfig = figure;
imagesc(slice)
axis off;
colormap(gray) 
clim([0, 255]);

% 关键修改：设置axes尺寸并消除内边距
ax = gca;
set(ax, 'Units', 'centimeters');
set(ax, 'Position', [0 0 xsize ysize]); % 让axes填满figure打印区域
set(ax, 'LooseInset', get(ax, 'TightInset')); % 移除axes额外内边距
axis image; % 强制图像宽高比匹配数据，禁止缩放

% 锁定打印参数，避免自动调整
set(bfig, 'Units','centimeters', 'Position',[0 0 xsize ysize])
movegui(bfig, 'center')

set(bfig, 'PaperUnits', 'centimeters');
set(bfig, 'PaperPosition',[xmarg ymarg xsize ysize])
set(bfig, 'PaperOrientation', 'landscape');
set(bfig, 'PaperPositionMode', 'manual'); % 禁止Matlab自动修改打印位置

printpreview

内容的提问来源于stack exchange，提问作者Bell