Recently, digital images have become the most used data, thanks to high internet speed and high resolution, cheap and easily accessible digital cameras. We generate, transmit and store millions of images every second. Most of these images are insignificant images containing only personal information. However, in many fields such as banking, finance, public institutions, and educational institutions, the images of many valuable objects like ID cards, photographs, credit cards, and transaction receipts are stored and transmitted to the digital environment. These images are very significant and must be secured. A valuable image can be maliciously modified by an attacker. The modification of an image is sometimes imperceptible even by the person who stored the image. In this paper, an active image forgery detection method that encodes and decodes image edge information is proposed. The proposed method is implemented by designing an interface and applied on a test image which is frequently used in the literature. Various tampering attacks are simulated to test the fidelity of the method. The method not only notifies whether the image is forged or not but also marks the tampered region of the image. Also, the proposed method successfully detected tampered regions after geometric attacks, even on self-copy attacks. Also, it didn't fail on JPEG compression.