Multicast-based content transmitting system and method, and device and method for estimating high-speed movement
The present invention relates to a multicast-based content transmitting system and method, and a device and method for estimating high-speed movement. Included are: a content providing device for generating N×M multicast stream channels having different transmission start times and transmission rates, providing N×M multicast stream channel lists, and transmitting content through one channel of N×M multicast stream channels; and a user terminal for selecting one channel of the N×M multicast stream channel lists provided from the content providing device and receiving content through the selected multicast stream channel.
1. A motion estimation apparatus, the apparatus comprising:
a processor configured to
create an n-th compared image and an n-th reference image having a value obtained by multiplying a pixel value by n times as an n-th pixel value of a pixel for each pixel of the compared image and the reference image,
create an n-th integral compared image and an n-th integral reference image by calculating pixel values up to set pixel coordinates for the n-th compared image and the n-th reference image,
calculate an n-th momentum of the compared image and an n-th momentum of the reference image for a set block using the n-th integral compared image and the n-th integral reference image,
calculate a block matching error using the n-th momentum of the compared image and the n-th momentum of the reference image, and
estimate a coordinate difference between a compared image block and a reference image block having a smallest block matching error as a motion vector.
2. The apparatus according to claim 1 , wherein said processor is configured to create the n-th compared image and the n-th reference image using Equation 1 below
O n ( x,y )= i ( x,y )* O n-1 ( x,y ), [Equation 1]
wherein i(x,y) expresses an original image of the compared image or the reference image, O n (x,y) expresses the n-th compared image or the n-th reference image, and (x,y) expresses the pixel coordinates.
3. The apparatus according to claim 1 , wherein said processor is configured to create the n-th integral compared image and the n-th integral reference image using Equation 2 below
I n ( X,Y )=Σ Y Σ X O n ( x,y ), [Equation 2]
wherein I n (x,y) expresses the n-th integral compared image or the n-th integral reference image, O n (x,y) expresses the n-th compared image or the n-th reference image, and (x,y) expresses the pixel coordinates.
4. The apparatus according to claim 1 , wherein said processor is configured to calculate the n-th momentum of four blocks including a set block for the compared image and the reference image using Equation 3 below
M n =I n ( x e ,y e )+ I n ( x e −1, y e −1)[ I n ( x e −1, y e )+ I n ( x e ,y e −1)], [Equation 3]
wherein I n (x, y) expresses the n-th integral compared image or the n-th integral reference image of a pixel or a block (x e , y e ), and (x e , y e ), (x e −1, y e −1), (x e −1, y e ) and (x e , y e −1) express the pixel coordinates or block coordinates.
5. The apparatus according to claim 1 , wherein said processor is configured to calculate at least one of SAD and SSD as the block matching error using Equation 4 below
SAD=[Σα n |M n,ref −M n,curr |]x γ and SSD=[Σβ n |M n,ref −M n,curr | 2 ]xγ, [Equation 4]
wherein M n,ref denotes the n-th momentum for the set block of the reference image, M n,curr denotes the n-th momentum for the set block of the compared image, α n and β u denote weighting factors of the n-th momentums, and γ denotes a constant.
6. An image encoding apparatus for estimating a motion at a high speed, the apparatus comprising:
a processor configured to
create an n-th compared image and an n-th reference image for a compared image and a reference image,
create an n-th integral compared image and an n-th integral reference image by calculating pixel values up to set pixel coordinates for the n-th compared image and the n-th reference image,
calculate an n-th momentum of the compared image and an n-th momentum of the reference image for a set block using the n-th integral compared image and the n-th integral reference image,
calculate a block matching error using an n-th momentum difference,
estimate a coordinate difference between a compared image block and a reference image block having a smallest block matching error as a motion vector,
create an estimated image for the compared image from the reference image using the estimated motion vector,
create a difference image of the compared image and the reference image, and
encode the created difference image.
7. A method of estimating a motion at a high speed, the method performed by a processor and comprising:
creating an n-th compared image and an n-th reference image having a value obtained by multiplying a pixel value by n times as an n-th pixel value of a pixel for each pixel of the compared image and the reference image;
creating an n-th integral compared image and an n-th integral reference image by calculating pixel values up to set pixel coordinates for the n-th compared image and the n-th reference image;
calculating an n-th momentum of the compared image and an n-th momentum of the reference image for a set block using the n-th integral compared image and the n-th integral reference image;
calculating a block matching error using a difference between the n-th momentum of the compared image and the n-th momentum of the reference image; and
estimating a coordinate difference between a compared image block and a reference image block having a smallest block matching error as a motion vector.
8. The method according to claim 7 , further comprising
based on the estimated motion vector, creating a difference image corresponding to the compared image.
9. The apparatus according to claim 1 , wherein
the processor is further configured to, based on the estimated motion vector, create a difference image corresponding to the compared image.