Temporal Noise Reduction Method for Noisy Image and Related Apparatus

A temporal noise reduction apparatus for a noisy image, comprising:

• a memory;
• and
• a processor coupled to the memory and configured to:
• acquire quantization noise of a first section of the noisy image, wherein the first section is any one of multiple sections divided from the noisy image;
• detect, according to the quantization noise of the first section, pixel positions of all pixels in a movement estimation neighborhood in a next frame after the pixels move from pixel positions in a current frame to the next frame, wherein the movement estimation neighborhood comprises neighbor pixels centered around a first pixel, and wherein the first pixel is any pixel in the first section;
• determine, according to a pixel position change situation of all the pixels in the movement estimation neighborhood that change from the current frame to the next frame, whether the first pixel is in a movement area or a still area;
• trigger execution of a first blending coefficient selection and a first temporal noise reduction when the first pixel is in the movement area;
• trigger execution of a second blending coefficient selection and a second temporal noise reduction when the first pixel is in the still area,
• wherein the first blending coefficient selection is configured to select a first blending coefficient according to a first frame difference of the first pixel and a preset first frame difference threshold when the first pixel is in the movement area,
• wherein the first frame difference is the difference between a pixel value of the first pixel in the current frame and a movement compensation pixel value of the first pixel in the previous frame,
• wherein the first temporal noise reduction is configured to calculate a first noise reduction pixel value corresponding to the first pixel according to the first blending coefficient, the pixel value of the first pixel in the current frame, and the movement compensation pixel value of the first pixel in the previous frame,
• wherein the movement compensation pixel value is a pixel value of a corresponding position of the first pixel in the current frame and is obtained after movement estimation and movement compensation are performed based on a noise reduction pixel of the first pixel in the previous frame,
• wherein the second blending coefficient selection is configured to select a second blending coefficient according to a second frame difference of the first pixel and a preset second frame difference threshold when the first pixel is in the still area,
• wherein the second frame difference is the difference between the pixel value of the first pixel in the current frame and a noise reduction pixel value of the first pixel in the previous frame, wherein the second frame difference threshold is greater than the first frame difference threshold,
• wherein the second temporal noise reduction is configured to calculate a second noise reduction pixel value corresponding to the first pixel according to the second blending coefficient, the pixel value of the first pixel in the current frame, and the noise reduction pixel value of the first pixel in the previous frame, and
• wherein the noise reduction pixel value is a pixel value of a corresponding position of the noise reduction pixel of the first pixel in the previous frame.