what is ground truth image? how to create it in matlab??
5 次查看(过去 30 天)
显示 更早的评论
Hi everyone,
I want to compare PSNR between some edge detection operator and the ground truth image.. But I confuse what the ground truth image is?? and how to create it in matlab?? thanks
0 个评论
采纳的回答
David Young
2012-1-3
"Ground truth" means a set of measurements that is known to be much more accurate than measurements from the system you are testing.
For example, suppose you are testing a stereo vision system to see how well it can estimate 3D positions. The "ground truth" might be the positions given by a laser rangefinder which is known to be much more accurate than the camera system.
Sometimes synthetic data are generated from a model, to test a system whose goal is to estimate parameters of the model. In such cases the "ground truth" is the known parameters of the model. Again stereo vision provides a good example: computer graphics can generate synthetic images from a 3D model, and then a stereo vision system can try to reconstruct the model. The original model is the "ground truth".
In the case of edge detection, it's much less clear what "ground truth" means, and in fact I don't think it's well defined, as edge detection generally involves making some (more or less) arbitrary choices. Nonetheless, I can think of two possible candidates: one is the output of an edge-detector which is generally accepted to be high-quality; the other is the edges drawn by an expert human looking at the image. Neither of these is really ground truth, however, and the term "gold standard" would be more applicable.
This comes down to a question to you: what is your ultimate goal? That is, why do you want "ground truth"?
更多回答(4 个)
Walter Roberson
2012-1-3
"ground truth" is not, as best I can tell, something that can be calculated. Please see http://www.mathworks.com/matlabcentral/answers/8745-oversegmentation-was-find-groundtruth-of-an-image
0 个评论
lina
2012-1-3
1 个评论
Walter Roberson
2012-1-3
You would have had to have been at the photo session with "Lena" in order to compare your image to the "ground truth" that was Lena herself at that time and make-up and lighting and angle.
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Detection 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!