Image processing method to generate, from a source image, an image of reduced size, called reduced image, whose ratio between the width and the height is equal to a predetermined value, called reduced ratio, comprising the following steps: - selecting one rectangular image part in said source image, - extracting said rectangular image part to generate said reduced image, said method being characterized in that, when the ratio between the width and height of said rectangular image part, called first ratio, is not equal to the reduced ratio, the width or, alternatively, the height of said rectangular image part is increased before the extraction step by a first value (ALD, AHH) on one side of said image part, called first side, and by a second value (ALG, AHB) on another side of said image part opposite to said first side, called second side, said first and second values being determined according to the following steps: - calculating (1310, 1320) a first increase (AL, AH) in width or, correspondingly, height such that the ratio between said width and said height of said rectangular image part modified by said first increase is equal to said reduced ratio, - calculating (1312, 1322) a first average saliency value (SMD, SMB) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said first side, - calculating (1311, 1321) a second average saliency value (SMG, SMH) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said second side, - calculating (1315, 1325) said first value (ALD, AHB) as being the product of said first increase and the ratio between said first average saliency value (SMD, SMB) and the sum of said first and second average saliency values, called total average saliency value, and - calculating (1314, 1324) said second value (ALG, AHH) as being the product of said first increase and the ratio between said second average saliency value (SMG, SMH) and said total average saliency value. - selecting one rectangular image part in said source image, - extracting said rectangular image part to generate said reduced image, said method being characterized in that, when the ratio between the width and height of said rectangular image part, called first ratio, is not equal to the reduced ratio, the width or, alternatively, the height of said rectangular image part is increased before the extraction step by a first value (ALD, AHH) on one side of said image part, called first side, and by a second value (ALG, AHB) on another side of said image part opposite to said first side, called second side, said first and second values being determined according to the following steps: - calculating (1310, 1320) a first increase (AL, AH) in width or, correspondingly, height such that the ratio between said width and said height of said rectangular image part modified by said first increase is equal to said reduced ratio, - calculating (1312, 1322) a first average saliency value (SMD, SMB) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said first side, - calculating (1311, 1321) a second average saliency value (SMG, SMH) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said second side, - calculating (1315, 1325) said first value (ALD, AHB) as being the product of said first increase and the ratio between said first average saliency value (SMD, SMB) and the sum of said first and second average saliency values, called total average saliency value, and - calculating (1314, 1324) said second value (ALG, AHH) as being the product of said first increase and the ratio between said second average saliency value (SMG, SMH) and said total average saliency value. - calculating (1310, 1320) a first increase (AL, AH) in width or, correspondingly, height such that the ratio between said width and said height of said rectangular image part modified by said first increase is equal to said reduced ratio, - calculating (1312, 1322) a first average saliency value (SMD, SMB) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said first side, - calculating (1311, 1321) a second average saliency value (SMG, SMH) from the values of perceptual interest associated with the pixels of the additional image part obtained by increasing the width or, correspondingly, height of said rectangular image part of said first increase to said second side, - calculating (1315, 1325) said first value (ALD, AHB) as being the product of said first increase and the ratio between said first average saliency value (SMD, SMB) and the sum of said first and second average saliency values, called total average saliency value, and - calculating (1314, 1324) said second value (ALG, AHH) as being the product of said first increase and the ratio between said second average saliency value (SMG, SMH) and said total average saliency value.