Image Watermarking with Go and imagetor

This project demonstrates a simple image watermarking application using Go and the imagetor module. It takes two images as input: a target image and a watermark image (logo). The application then overlays the watermark onto the target image and saves the resulting image.

Features:

• Image Loading and Saving: The project utilizes Go's built-in image library to load and save images in various formats (JPEG, PNG).
• Image Manipulation: The imagetor module provides functions to convert images to tensors and perform overlay operations.
• Performance Measurement: The code tracks the execution time to provide insights into the performance of the watermarking process.
• Image Flipping: The imagetor module now includes the UpSideDown function, which flips an image vertically.
• Grayscale Conversion: The imagetor module now includes the GrayScale function, which converts an image to grayscale using the LUMINOSITY method.
• Image Rotation: The imagetor module now includes the Rotate function, which rotates an image by a specified angle using bilinear interpolation.

Dependencies:

• imagetor: This module is assumed to be a custom module providing image manipulation functions. You will need to install and configure it according to its documentation.

Usage:

1. Install Go: Ensure you have Go installed on your system.
2. Install Dependencies: Install the imagetor module (or any other required dependencies).
3. Prepare Images: Place the target image (large-image.jpg) and the watermark image (logo.png) in the same directory as the main.go file.
4. Run the Application: Execute the main.go file using the go run command.
5. Output: The resulting watermarked image will be saved as output.jpg in the same directory.

Code Breakdown:

• openImage function: Loads an image from a given path and returns an image.Image object.
• saveImage function: Saves an image.Image object to a specified path in JPEG format.
• main function:
  • Loads the target image and the watermark image.
  • Converts both images to tensors using imagetor.ImageToTensor.
  • Overlays the watermark tensor onto the target tensor using imagetor.AddOverlay.
  • Converts the resulting tensor back to an image using imagetor.TensorToImage.
  • Saves the watermarked image to output.jpg.
  • Measures and prints the execution time.

Customization:

• Watermark Image: You can replace logo.png with any desired watermark image.
• Output Format: Modify the saveImage function to save the output in a different format (e.g., PNG).
• Overlay Position: The imagetor module likely provides options to adjust the position and size of the watermark.
• Image Flipping: Use the imagetor.UpSideDown function to flip the target or watermark image before overlaying.
• Grayscale Conversion: Use the imagetor.GrayScale function to convert the target or watermark image to grayscale before overlaying.
• Image Rotation: Use the imagetor.Rotate function to rotate the target or watermark image by a specified angle before overlaying.

Note:

This project serves as a basic example of image watermarking in Go using the imagetor module. It can be extended to include more advanced features like transparency control, watermark resizing, and multiple watermarking.

This project provides a starting point for building a more comprehensive image watermarking application using Go and the imagetor module.