A video signal decoding device comprising a processor, wherein the processor is configured to: recursively determine a result value that indicates a partitioning direction of a current transform block, TB, which is a vertical direction or a horizontal direction and split the current transform block into a plurality of transform blocks on the basis of the result value; and decode the current transform block based on the plurality of transform blocks, wherein when a width of the current transform block is less than or equal to a maximum transform block width or a first value is less than or equal to a second value, the result value is a value indicating that the partitioning direction is the horizontal direction, when the width of the current transform block is greater than the maximum transform block width and the first value is greater than the second value, the result value is a value indicating that the partitioning direction is the vertical direction, wherein i) when a color component of the current transform block is a luma component: the first value is obtained by multiplying the width of the current transform block and 1, and the second value is obtained by multiplying the height of the current transform block and 1, ii) when the color component of the current transform block is a chroma component: the first value is obtained by multiplying the width of the current transform block and SubWidthC, and the second value is obtained by multiplying the height of the current transform block and SubHeightC, wherein each of the SubWidthC and the SubHeightC is a variable determined based on a chroma format related to the current transform block. recursively determine a result value that indicates a partitioning direction of a current transform block, TB, which is a vertical direction or a horizontal direction and split the current transform block into a plurality of transform blocks on the basis of the result value; and decode the current transform block based on the plurality of transform blocks, wherein when a width of the current transform block is less than or equal to a maximum transform block width or a first value is less than or equal to a second value, the result value is a value indicating that the partitioning direction is the horizontal direction, when the width of the current transform block is greater than the maximum transform block width and the first value is greater than the second value, the result value is a value indicating that the partitioning direction is the vertical direction, wherein i) when a color component of the current transform block is a luma component: the first value is obtained by multiplying the width of the current transform block and 1, and the second value is obtained by multiplying the height of the current transform block and 1, ii) when the color component of the current transform block is a chroma component: the first value is obtained by multiplying the width of the current transform block and SubWidthC, and the second value is obtained by multiplying the height of the current transform block and SubHeightC, wherein each of the SubWidthC and the SubHeightC is a variable determined based on a chroma format related to the current transform block. i) when a color component of the current transform block is a luma component: the first value is obtained by multiplying the width of the current transform block and 1, and the second value is obtained by multiplying the height of the current transform block and 1, the first value is obtained by multiplying the width of the current transform block and 1, and the second value is obtained by multiplying the height of the current transform block and 1, ii) when the color component of the current transform block is a chroma component: the first value is obtained by multiplying the width of the current transform block and SubWidthC, and the second value is obtained by multiplying the height of the current transform block and SubHeightC, wherein each of the SubWidthC and the SubHeightC is a variable determined based on a chroma format related to the current transform block. the first value is obtained by multiplying the width of the current transform block and SubWidthC, and the second value is obtained by multiplying the height of the current transform block and SubHeightC, wherein each of the SubWidthC and the SubHeightC is a variable determined based on a chroma format related to the current transform block.