In some sample files, when display usage, it will use the cpp files' name as binary executable files' name. However, it should be actual file name. So I use the argv[0] instead of cpp files' name.

For example, sample files code as follows.

static void help()
{
    printf("\nThis sample demonstrates Canny edge detection\n"
           "Call:\n"
           "    /.edge [image_name -- Default is fruits.jpg]\n\n");
}

Now, I update it to:

static void help(char** argv)
{
    printf("\nThis sample demonstrates Canny edge detection\n"
           "Call:\n"
           "    %s [image_name -- Default is fruits.jpg]\n\n", argv[0]);
}

Pull Request Readiness Checklist

• I agree to contribute to the project under OpenCV (BSD) License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or other license that is incompatible with OpenCV
• The PR is proposed to proper branch
• There is reference to original bug report and related work
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake

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