Hide Information The information is private or confidential so that no one can disclose or alter it. There are generally two techniques used to hide information, one of which is digital markup, which is used for two main purposes:
- Proof of intellectual property
Another method used to hide information is called Steganography, which is generally used to hide data and prevent unauthorized access.
Steganography and cryptography are both used to ensure the confidentiality of information. But there is a fundamental difference between the two. In encryption, you can easily recognize encrypted information. But in steganography, even what is encrypted is hidden, that is, at first glance, we are dealing with a normal file or data. In fact, steganography is used for top-secret missions and situations where cryptography is not usable. For example, you can use this technology in the field of copyright. Encrypted copyright information stored on a file can be easily deleted. But if this code is included in the contents of the file, they are not easily identifiable so that there is a risk of deleting them.
The art and science of communication is such that Even if the message is not detected, it is the official definition of steganography. Simple forms of steganography have been used to hide information for hundreds of years, but with the proliferation of electronic files, humans have come up with new techniques for hiding information.
Hide information is a method that uses things like video, photos, audio files, and as a cover. These days, for example, various subtle signs are embedded in videos and photos, often containing watermarks to prevent unauthorized copying of the work. Research into hiding information in backup files has increased over the past two decades as the business world has shown interest in it.
Methods of Hiding Information In the video
Steganography in Video files based on the use of YCbCr color space:
YCbCr is a family of color spaces used as part of the graphic popline in digital and video photography systems. It becomes. YCbCr represents colors in approximately three values:
- Y=brightness (can be said to be the brightness of the image)
- Cb=blue base color
- Cr=red base color
Green is obtained by combining these three values.
YCbCr color space is a space that can eliminate red, blue, and green correlations in a given image, because less correlation between colors means less distortion. This method is commonly used in video images in which humans are present, and elements such as human skin color grading are used to hide data. Keep in mind that human skin color can vary from black to reddish white, in different people and races. The purpose of using this method is to fight against fake passports, thus saving people's information stored in their images and eliminating the possibility of forgery.
conversion Domain Embedding:
This is a sophisticated way to hide information in images. Various algorithms and transformations are used on an image to find information. One of these methods is called DCT, which stands for direct cosine transformation. This converter applies to jpeg images and converts 8.8 consecutive pixel blocks to 64 DCT coefficients.
DTC helps the image to Multiple components (spectral subbands) of different importance (according to the visual quality of the image) are separated, embedding in the DCT domain is done simply by changing the DCT coefficients, for example, one of the limitations of embedding in the DCT domain is that a large number of 64 The coefficients are zero, and changing a large number of values from zero to non-zero can affect the compression rate.Insertion)
This method is very popular because of its simplicity. The least valuable bit per byte (each byte equals 8 bits) in each image is used to store hidden data. The changes that occur in the photo by doing this are so small that they are not recognizable to the naked eye. Since this technique uses one image per pixel, non-waste compression formats such as bmp and gif should be used. If lost formats are used, some of the hidden information may be lost.
Consider video as separate images:
In this method, each video frame is considered as a separate image and you can hide the information in it. The main advantage of this method is that you can use the algorithms used in image steganography and watermark embedding. But this method takes a lot of time for processes and calculations.
Instant video steganography:
This method involves hiding information on the output image (for example, an image that is played from a billboard). In this method, every frame that the device shows at any given moment, regardless of whether it is a photo or text or anything else, is considered as an image. The system then splits the image into small blocks. If the color of the pixels in a block are the same, the color attribute system changes some of them to a certain extent, and as a result the information inside the image will be hidden.
In this article, we tried to talk about different ways to hide information in a file, especially video files and how to use it. The fact is that this path can greatly increase data security and prevent many frauds and scams. It remains to be seen how the methods of doing this will change with the advancement of technology.