can't save image with transparent background

I want to save some figure I draw into png format with transparent background. I set the background to transparent by using 'color' property and I do see the figure shown has a transparent background. The only problem is that when i save the image, the image background is not transparent any more (I put the image in a powerpoint to test the transparency). The code is as follow:

%SAVE IMAGE
image=gcf;
%set(image,'color','none');
saveas(image,'test','png');

Can anyone tell me what's wrong here and what I can do to correct this? Thanks!

Answer 1

[Matt Fig]

I don't know what you are doing wrong but I rarely ever rely on MATLAB to get these kinds of things right. I use this instead: export_fig

Answer 2

[Kaustubha Govind]

See Bug Report #299665

Answer 3

[cui,xingxing]

since Matlab R2020a, use "exportgraphics", for example ,you can do like this

x = 0:.1:2*pi;
y = sin(x);
% save to transparented image
figure;
plot(x,y,'LineWidth',4);
set(gcf, 'color', 'none');    
set(gca, 'color', 'none');
exportgraphics(gcf,'transparent.eps',...   % since R2020a
    'ContentType','vector',...
    'BackgroundColor','none')

[Nicolette]

This is not trasnparent. It just makes the background black instead of white.