Circuit and method for decoding an encoded version of an image having a first resolution directly into a decoded version of the image having a second resolution
View Patent ↗An image processing circuit includes a processor that receives an encoded portion of a first version of an image. The processor decodes this encoded portion directly into a decoded portion of a second version of the image, the second version having a resolution that is different than the resolution of the first version. Therefore, such an image processing circuit can decode an encoded hi-res version of an image directly into a decoded lo-res version of the image. Alternatively, the image processing circuit includes a processor that modifies a motion vector associated with a portion of a first version of a first image. The processor then identifies a portion of a second image to which the modified motion vector points, the second image having a different resolution than the first version of the first image. Next, the processor generates a portion of a second version of the first image from the identified portion of the second image, the second version of the first image having the same resolution as the second image.
1. An image processing circuit, comprising:
a processor operable to,
modify a motion vector associated with a portion of a first version of a first image to be compatible with a second image having a different resolution than the first version of the first image,
identify a portion of the second image to which the modified motion vector points,
convert a first group of residuals that represents the portion of the first version of the first image into a second group of residuals that represents a portion of a second version of the first image, the second version having the same resolution as the second image, and
mathematically combine the second group of residuals and pixel values that represent the identified portion of the second image to generate pixel values that represent the portion of the second version of the first image.
2. The image processing circuit of claim 1 wherein the second image and the second version of the first image have a lower resolution than the first version of the first image.
3. The image processing circuit of claim 1 wherein:
the second image and the second version of the first image have a lower resolution than the first version of the first image; and
the second group of residuals has fewer residuals than the first group of residuals.
4. The image processing circuit of claim 1 wherein the processor is operable to modify the motion vector by multiplying the motion vector with a scaling factor between the first version of the first image and the second image.
5. The image processing circuit of claim 1 wherein the modified motion vector has a resolution of less than ½ pixel in at least one dimension.
6. The image processing circuit of claim 1 wherein the processor is operable to calculate the pixel values that represent the identified portion of the second image.
7. The image processing circuit of claim 1 wherein the processor is operable to mathematically combine by summing each of the residuals in the second group with a respective one of the pixel values that represent the identified portion of the second image.
8. The image processing circuit of claim 1 wherein the pixel values that represent the identified portion of the second image correspond to interpolated pixels that are offset from actual pixels of the second image.
9. The image processing circuit of claim 1 wherein the processor is operable to convert the first group of residuals by:
selecting a first group of transform values from a second group of transform values that represents the first group of residuals, the first group of transform values being smaller than the second group of transform values; and
converting the first group of transform values directly into the second group of residuals.
10. A method, comprising:
modifying a motion vector associated with a portion of a first version of a first image to be compatible with a second image having a different resolution than the first version of the first image;
identifying a portion of the second image to which the modified motion vector points;
converting a first group of residuals that represents the portion of the first version of the first image into a second group of residuals that represents a portion of a second version of the first image, the second version having the same resolution as the second image; and
mathematically combining the second group of residuals and pixel values that represent the identified portion of the second image to generate pixel values that represent the portion of the second version of the first image.
11. The method of claim 10 wherein the second image and the second version of the first image have a lower resolution than the first version of the first image.
12. The method of claim 10 wherein:
the second image and the second version of the first image have a lower resolution than the first version of the first image; and
the second group of residuals has fewer residuals than the first group of residuals.
13. The method of claim 10 wherein the modifying comprises multiplying the motion vector with a scaling factor between the first version of the first image and the second image.
14. The method of claim 10 wherein the modifying comprises modifying the motion vector to have a resolution of less than ½ pixel in at least one dimension.
15. The method of claim 10 further comprising calculating the pixel values that represent the identified portion of the second image.
16. The method of claim 10 wherein the mathematically combining comprises summing each of the residuals in the second group with a respective one of the pixel values that represent the identified portion of the second image.
17. The method of claim 10 , further comprising calculating the pixel values that represent the identified portion of the second image by interpolating between actual pixels of the second image.
18. The method of claim 10 wherein the converting comprises:
selecting a first group of transform values from a second group of transform values that represents the first group of residuals, the first group of transform values being smaller than the second group of transform values; and
converting the first group of transform values directly into the second group of residuals.