Video compression and encoding method
Disclosed herein is a method for decoding a video signal having at least one frame with a plurality of blocks including a current block, including generating, for at least a selected pixel in the current block, a predicted value for at least one pixel located in a row i and a column j of the current block using a processor and according to the following equation: X ij =L i +A j −C; wherein X ij is the predicted value, L i is the value of a pixel to the left of the current block, A j is the value of a pixel in a row above the current block and C is the value of a pixel in the row above and the column to the left of the current block and decoding the current block using the predicted value.
1. A method for decoding a video signal having a plurality of images, comprising:
subdividing each of the plurality of images into a set of fixed partitions;
selecting one of a plurality of alternative subdivisions using a processor to further subdivide at least one of the set of fixed partitions into one or more segments, wherein the selected alternative subdivision is chosen based on a combined error score determined in an encoder by:
further subdividing each of the set of fixed partitions into segments according to the plurality of alternative subdivisions;
selecting an optimal motion vector for each segment in each of the plurality of alternative subdivisions based on an error score for each segment; and
calculating the combined error score for each of the plurality of alternative subdivisions equal to the sum of the error scores for each segment of a corresponding subdivision;
wherein the selected alternative subdivision corresponds to the alternative subdivision having the lowest combined error score.
2. The method of claim 1 , further comprising:
receiving and decoding a motion vector for each segment in the selected alternative subdivision.
3. The method of claim 1 , wherein each of the one or more segments including at least one block of pixels.
4. The method of claim 1 , wherein the optimal motion vector is selected from a previously encoded partition.
5. The method of claim 1 , wherein the plurality of alternative subdivisions comprises a fixed set of subdivisions.
6. The method of claim 1 , wherein at least a portion of the plurality of alternative subdivisions comprises at least one of:
a) a fixed set of subdivisions;
b) a set of subdivisions derived from labeling functions; or
c) both a first set of fixed subdivisions and a second set of subdivisions that are derived from labeling functions.
7. The method of claim 6 , wherein the labeling functions includes at least one of the following: grouping blocks into segments according to variance; grouping blocks into segments according to average pixel intensity; or grouping blocks into segments according to error score.
8. The method of claim 6 , wherein multiple subdivisions are created using each labeling function of different thresholds.
9. The method of claim 1 , wherein selecting the motion vector further comprises at least one of the following:
performing a motion search for each block or segment and encoding the resulting new motion vectors;
using the same motion vector as the block or segment to the left of the current block or segment;
using the same motion vector as the block or segment above the current block or segment;
using a zero motion vector (0,0); or
using a previously encoded motion vector from a block or segment that is not immediately adjacent to the current block or segment.
10. The method of claim 1 , wherein the error score is calculated using a rate distortion calculation.
11. The method of claim 1 , wherein the error score is calculated using a prediction error calculated as one of the sum squared error or the sum of absolute differences.
12. An apparatus for decoding a video signal having at least one image, comprising:
a memory; and
a processor configured to execute instructions stored in the memory to: subdivide each image into a set of fixed partitions;
select one of a plurality of alternative subdivisions using a processor to further subdivide at least one of the set of fixed partitions into one or more segments, wherein the selected alternative subdivision is chosen based on a combined error score determined in an encoder by:
further subdivide each of the set of fixed partitions into segments according to the plurality of alternative subdivisions;
select an optimal motion vector for each segment in each of the plurality of alternative subdivisions based on an error score for each segment; and
calculate the combined error score for each of the plurality of alternative subdivisions equal to the sum of the error scores for each segment of a corresponding subdivision;
wherein the selected alternative subdivision corresponds to the alternative subdivision having the lowest combined error score.
13. The method of claim 12 , wherein the processor is further configured to execute instructions stored in the memory to:
receive and decode a motion vector for each segment in the selected alternative subdivision.
14. The method of claim 12 , wherein each of the one or more segments including at least one block of pixels.
15. The method of claim 12 , wherein the optimal motion vector is selected from a previously encoded partition.
16. The method of claim 12 , wherein the combined error score calculating step iv) of a current partition uses error scores calculated from a previously encoded partition.
17. The method of claim 12 , wherein the selected alternative subdivision is selected from a previously encoded partition.
18. The method of claim 12 , wherein the plurality of alternative subdivisions comprises a fixed set of subdivisions.
19. A method for decoding a video signal having a plurality of images, each image partitioned into a set of 16×16 block of pixels, comprising:
receiving an indication of a selection of one of a plurality of alternative subdivisions for at least one of the 16×16 block of pixels;
subdividing, using a processor, the at least one 16×16 block of pixels into a plurality of segments based on the indication;
wherein the indication of the selection of one of the plurality of alternative subdivisions is determined in an encoder by:
further subdividing at least some of the 16×16 block of pixels into segments according to the plurality of alternative subdivisions;
selecting a motion vector for each segment in each of the plurality of subdivisions based on an error score for each segment; and
calculating a combined error score for each of the plurality of alternative subdivisions equal to the sum of the error scores for each segment of a corresponding subdivision;
wherein the indication is associated with the alternative subdivision having the lowest combined error score.
20. The method of claim 19 , wherein the indication is transmitted in a bitstream representing the video signal.