Issue Saving image with text overlay to png

14 次查看（过去 30 天）
Erick Oberstar
Erick Oberstar 2019-7-16
移动：Walter Roberson 2025-10-29，17:00
I am having issues saving an image that has been displayed in a figure, with a couple markers plotted at specific coordinates and then text overlaid using the text function. I am trying to safe this off as a png via saveas(gcf,'filename.png'); and the figure exports but the overlaid text is missing. The title and the marker points I plotted show up but no text. Below is the figure.
Attached is the exported png using saveas
My code looks as follows:
figure; imshow(img,[]);
hold on;
plot(Stats(TestNum).Centroid(1),Stats(TestNum).Centroid(2),'b*');
set(gca, 'ActivePositionProperty', 'OuterPosition');
[filepath,name,ext] = fileparts(files(TestNum).name);
title({[];name;['Original Image With Centroid Marked']},'FontSize',FontSize);
text(20,500,{['Area = ',num2str(Stats(TestNum).Area.*pixel_scale^2,'%3.2f'),'mm^2'];...
['Eccentricity = ',num2str(Stats(TestNum).Eccentricity,'%3.2f')];...
['Orientation = ',num2str(Stats(TestNum).Orientation,'%3.2f'),char(176)];...
['Major Axis Length = ',num2str(Stats(TestNum).MajorAxisLength.*pixel_scale,'%3.2f'),'mm'];...
['Minor Axis Length = ',num2str(Stats(TestNum).MinorAxisLength.*pixel_scale,'%3.2f'),'mm']},...
'Color','white','FontSize',FontSize);
saveas(gcf,[pwd '\output\Test ',num2str(TestNum),'\TubeMidpointCrossSection - Test ',num2str(TestNum),'.png']);
  1 个评论
Will Reeves
Will Reeves about 4 hours 前
移动：Walter Roberson about 3 hours 前
I have the same problem. My issue is, like the above, the image I'm writing text on top of is mostly black - I need white text. Please can "saveas" actually save "WYSIWYG-like"?

请先登录，再进行评论。

请先登录，再回答此问题。

回答（3 个）

Walter Roberson
Walter Roberson 2019-7-16
I recommend you take a different approach. Instead of plotting on the image and text() on the image, use the Computer Vision insertText and insertShape routines to etch the information into an RGB array. After that is done, imwrite() the array.
Jia-Sheng Hong
Jia-Sheng Hong 2020-1-8
The text do exist after you save it, however, it become black again. You can set the 'BackgroundColor' of the text to white instead of set the text to white, and it should work.
Will Reeves
Will Reeves about 4 hours 前
编辑：Will Reeves about 3 hours 前
Sorry! I knew I once had the answer to this somewhere...
You need to put the line:
set(gcf, 'InvertHardCopy', 'off');
immediatly before issuing the "saveas" command.

类别

在 Help Center 和 File Exchange 中查找有关 Printing and Saving 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by