Update radon_transform.hpp

Author: sturkmen72

modules/ximgproc/include/opencv2/ximgproc/radon_transform.hpp

@@ -13,17 +13,39 @@ namespace cv { namespace ximgproc {
  * @brief Computes the Radon transform of a given 2D image.
  *
  * The Radon transform is often used in image processing, particularly in applications
- * like computed tomography, to analyze the structure of an image.
+ * like computed tomography, to analyze the structure of an image by projecting it along
+ * different angles. This function calculates the Radon Transform over a specified range
+ * of angles.
+ *
+ * The output type will vary depending on the input type:
+ * - If the input type is CV_8U, the output will be CV_32S.
+ * - If the input type is CV_32F or CV_64F, the output will be CV_64F.
+ *
+ * The size of the output matrix depends on whether cropping is applied:
+ * - Without cropping, the output size will be `num_of_integral x src_diagonal_length`.
+ * - With cropping (circular), the output size will be `num_of_integral x min_edge`, 
+ *   where `min_edge` is the smaller dimension of the cropped square.
+ *
+ * See https://engineering.purdue.edu/~malcolm/pct/CTI_Ch03.pdf for more details.
  *
  * @param src The input image on which the Radon transform is to be applied.
  *            Must be a 2D single-channel array (e.g., grayscale image).
  * @param dst The output array that will hold the result of the Radon transform.
- * @param theta The angle increment in degrees for the projection.
+ *            The type of the output will depend on the input image type.
+ * @param theta The angle increment in degrees for the projection (resolution of the transform).
+ *              Default is 1 degree.
  * @param start_angle The starting angle for the Radon transform in degrees.
+ *                    Default is 0 degrees.
  * @param end_angle The ending angle for the Radon transform in degrees.
- *                  The difference between end_angle and start_angle must be positive when multiplied by theta.
- * @param crop A flag indicating whether to crop the input image to a square or circular shape before transformation.
- * @param norm A flag indicating whether to normalize the output image to the range [0, 255] after computation.
+ *                  Default is 180 degrees. The difference between end_angle and start_angle must
+ *                  be positive when multiplied by theta.
+ * @param crop A flag indicating whether to crop the input image to a square or circular shape
+ *             before the transformation. If enabled, the image is first cropped to a square
+ *             (smallest dimension) and then transformed into a circle.
+ * @param norm A flag indicating whether to normalize the output image to the range [0, 255] after
+ *             computation and convert the type to `CV_8U`. If normalization is not enabled,
+ *             the output will retain its original data range.
+ *
  */
 CV_EXPORTS_W void RadonTransform(InputArray src,
                                       OutputArray dst,