Displaying frames captured by getframe(h) at original size

Question

Donald Liu 2021-10-7

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1468676-displaying-frames-captured-by-getframe-h-at-original-size

评论： Donald Liu 2021-10-7

I captured multiple frames from a figure, and would like to play them back one frame at a time. Please see the below example code:

h = figure;
for i=1:10
    plot(rand(20, 1));
    grid
    title('Original figure');
    xlabel('This is the original x label.');
    MV(i) = getframe(h);
    pause(0.01);
end
% The image displayed in this portion is *smaller* than the original plot,
% as it tries to fit the entire figure within the original axes
for i=1:10
    image(MV(i).cdata);
%     movie(h, MV(i));
    pause;
end

The problem is, when displayed using "image(MV(i).cdata)", the entire content of the figure has to fit within the plotting axes, including title and labels, so there's a shrinkage. I could use "movie(h, MV(i))", which does not cause this rescaling, but "movie" has the bad habbit of clearing the figure each time, so the display is flashing annoyingly. Do you have better solutions? Thanks in advance!

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Chunru 2021-10-7

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1468676-displaying-frames-captured-by-getframe-h-at-original-size#answer_803411

You can use "imshow" which by default show images in 100% magnification. "doc imshow" for more details.

3 个评论
显示 1更早的评论隐藏 1更早的评论

Image Analyst 2021-10-7

Maybe truesize()?

Donald Liu 2021-10-7

truesize did not seem to do what I intended, imshow is still displayed with ax2, and the whole figure is resized automatically:

h = figure;
ax1 = axes('Position', [0.49479      0.20139      0.41276      0.55556]);
ax2 = axes('Position', [0.13      0.52778      0.30359      0.39722]);
for i=1:10
    axes(ax1);
    plot(rand(20, 1));
    grid
    title(sprintf('Original figure %d', i));
    xlabel('This is the original x label.');
    axes(ax2);
    plot(rand(100, 1));
    MV(i) = getframe(h);
    pause(0.01);
end
% Set up a new axes for use by imshow, rather than using the current axes
% axes('Position', [0 0 1 1]);
for i=1:10
    imshow(MV(i).cdata, 'Border', 'tight');
    truesize();
%     image(MV(i).cdata);
    pause(0.1);
end