What is the difference between good noise and bad noise (for steganography in images)?
First of all we need to know what ‘Noise’ really is. Noise refers to the density of the amount of the data that is present in an image at a particular time, i.e. the more the complexity with in an image,the more chances of hiding data securely.
Good Noise refers to that image which has many colors or faces.In other words we can say an image is said to be having good noise if the data can be hided in the image in plain sight and no one can even wonder about the image carrying an hidden data thus, the image provides such area where the data could be hide easily and will be tough to guess that something is wrong with the image.Therefore the image which depicts such type of properties and coherence are often termed as good noises within images.
And,the images which did not possess such type of features or density in which the data can not be hided in plain sight or the hidden data can easiky be guessed are known as the poor side or Bad Noise within images.
Here are two images,the image with more complexion and density and where the data could be easily hided is an example of good noise and the image with simple plain text and low density and where the hidden data could easily be depicted or cracked is an example of poor density.