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# EasyImage - Pre-Processing Images

[`EasyImage`](../../../doxygen_cpp/classeVision_1_1EasyImage.html) [<sub>.NET</sub>](../../../doxygen_cs/classeVision_1_1EasyImage.html) [<sub>Python</sub>](../../../doxygen_python/classeVision_1_1EasyImage.html) operations prepare images so that further processing gets better results by:

* Isolating defects using thresholding or intensity transformations
* Compensating perspective effects (for non-flat surfaces such as a bottle label)
* Processing complex or disconnected shapes using flexible masks

The main functions are:

| [Intensity transformations](intensity_transformation.html.md)             | Change the gray-level of each pixel to clarify objects (histogram stretching).                                                      |
|--------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------|
| [Thresholding](thresholding.html.md)                          | Transforms a binary image into a bi- or tri-level grayscale image by classifying the pixel values.                                  |
| [Path profiling](profile.html.md)                        | Samples a series of pixel values sampled along a line, a path or a contour in an image.                                             |
| [Arithmetic and logic](arithmetic_and_logic.html.md)                  | Functions manipulating pixels in two images, or one image and a constant.                                                           |
| [Linear filtering](linear_filtering.html.md)                      | Functions using linear combinations of neighboring pixels (convolution) to highlight features in an image.                          |
| [Non-linear filtering](non-linear_filtering.html.md)                  | Functions using non-linear combinations of neighboring pixels (using a kernel) to highlight a shape, or to remove noise.            |
| [Geometric transforms](geometric_transforms.html.md)                  | Moves selected pixels to realign, resize, rotate and warp.                                                                          |
| [Noise reduction and estimation](noise_reduction_and_estimation.html.md)        | Functions ensuring that noise does not unacceptably influence other operations (thresholding, high-pass filtering).                 |
| [Scalar gradient](scalar_gradient.html.md)                       | Generates a gradient direction or gradient magnitude map from a gray-level image.                                                   |
| [Vector operations](vector_operations.html.md)                     | Extracts 1-dimensional data from an image into a vector, for example to detect scratches or outlines, or to clarify images.         |
| [Canny edge detector](canny_edge_detector.html.md)                   | Returns a BW8 image of the edges found in a BW8 image.                                                                              |
| [Harris corner detector](harris_corner_detector.html.md)                | Returns a vector of points of interest in a BW8 image.                                                                              |
| [Overlay](overlay.html.md)                               | Overlays an image on top of a color image.                                                                                          |
| [Operations on interlaced video frames](operations_on_interlaced_video_frames.html.md) | Eliminates interlaced image artifacts by rebuilding or re-aligning fields.                                                          |
| [Computing image statistics](computing_image_statistics.html.md)            | Displays different statistics about an object or an image.                                                                          |
| [Fourier transform](fourier_transform.html.md)                     | Represents an image by its frequential components to process the image and perform specific filtering.                              |
| [Gabor filter](gabor_filter.html.md)                          | Analyzes textures or creates features for a classifier by convolving the image with a wavelet to detect specific frequency content. |
| [HDR fusion](hdr_fusion.html.md)                            | Fuses different images into a single one that contains all the details exacerbated at each exposure level.                          |
| [Image stitching](image_stitching.html.md)                       | Combines partial images to build a final image that appears to have been captured in a single shot.                                 |