Apparatus and method for providing compensation information for demura and display driving apparatus using compensation information

1. An apparatus for providing compensation information for demura, the apparatus comprising:

a compensation value provision unit configured to provide compensation values of pixels; and

a compression unit configured to divide a screen into a plurality of blocks, generate a primary compression map and a representative value for each block by performing primary compression on compensation values of pixels for each block, and generate a secondary compression map and a reference value by performing the secondary compression on representative values of the blocks,

wherein the primary compression comprises:

extracting the representative value for the compensation values of the block,

extracting difference values between the representative values and the compensation values, and

generating the primary compression map corresponding to pixels of the block by the difference values, and

wherein the secondary compression comprises:

setting the reference value of the representative values,

performing differential coding on the representative values by using the reference value, and

generating the secondary compression map corresponding to the blocks by coding values that are generated as results of the differential coding.

2. The apparatus of claim 1 , wherein the compensation value provision unit provides, as the compensation values, coefficient values of coefficients of a compensation equation for demura of the pixels.

3. The apparatus of claim 1 , wherein the compression unit provides the primary compression map, the reference value, and the secondary compression map as compensation information.

4. The apparatus of claim 1 , wherein:

the compensation value provision unit provides location information and the compensation values for the pixels, and

the compression unit generates the primary compression map to which the difference values have been mapped by using the location information and the secondary compression map to which the coding values have been mapped corresponding to the blocks.

5. The apparatus of claim 1 , wherein:

the primary compression map comprises a two-dimensional table corresponding to pixels of the block, and

the secondary compression map comprises the two-dimensional table corresponding to the blocks.

6. The apparatus of claim 1 , wherein the compression unit extracts, as the representative value, the compensation value of the pixel that has been disposed at a center of the block.

7. The apparatus of claim 1 , wherein the compression unit

calculates a middle value between a maximum value and minimum value of the compensation values of the pixels included in the block, and

extracts, as the representative value, the compensation value corresponding to the middle value.

8. The apparatus of claim 1 , wherein the compression unit

calculates an average value of the compensation values of the pixels included in the block, and

extracts, as the representative value, the compensation value corresponding to the average value.

9. The apparatus of claim 1 , wherein the compression unit

performs quantization for representing the extracted difference values as a preset number of bits, and

generates, as the primary compression map, a bitmap comprising the quantized difference values.

10. The apparatus of claim 9 , wherein the compression unit sets, as a preset value, the difference value that has deviated from a range in which the extracted difference values are represented as the preset number of bits through the quantization.

11. The apparatus of claim 10 , wherein the compression unit

quantizes the difference value having a value greater than a value capable of being represented as the preset number of bits, as a maximum value capable of being represented as the preset number of bits, and

quantizes the difference value having a value smaller than a value capable of being represented as the preset number of bits, as a minimum value capable of being represented as the preset number of bits.

12. A method of providing compensation information for demura, the method comprising:

dividing a screen into a plurality of blocks;

performing primary compression on compensation values of pixels for each block, and generating a primary compression map and a representative value for the primary compression of the block; and

performing secondary compression on representative values of the blocks, and generating a secondary compression map and a reference value for the secondary compression of the block,

wherein the primary compression comprises:

extracting the representative value for the compensation values of the block,

extracting difference values between the representative values and the compensation values, and

generating the primary compression map corresponding to pixels of the block by the difference values, and

wherein the secondary compression comprises:

setting the reference value of the representative values,

performing differential coding on the representative values by using the reference value, and

generating the secondary compression map corresponding to the blocks by coding values that are generated as results of the differential coding.

13. The method of claim 12 , wherein the compensation values correspond to coefficient values of coefficients of a compensation equation for demura of the pixels.

14. The method of claim 12 , wherein:

the primary compression map comprises a two-dimensional table corresponding to pixels of the block, and

the secondary compression map comprises the two-dimensional table corresponding to the blocks.

15. The method of claim 12 , wherein the representative value corresponds to the compensation value of the pixel that has been disposed at a center of the block.

16. The method of claim 12 , further comprising:

calculating a middle value between a maximum value and minimum value of the compensation values of the pixels included in the block, and

extracting, as the representative value, the compensation value corresponding to the middle value.

17. The method of claim 12 , wherein the representative value corresponding to an average value of the compensation values of the pixels included in the block.

18. The method of claim 12 , further comprising:

performing quantization for representing the extracted difference values as a preset number of bits,

wherein the primary compression map is generated as a bitmap comprising the quantized difference values, and

the quantization comprises setting, as a preset value, the difference value that has deviated from a range in which the extracted difference values are represented as the preset number of bits.

19. A display driving apparatus comprising:

a compensation information storage unit configured to store and provide primary compression maps having difference values, a secondary compression map having coding values, and a reference value;

a compensation value generation unit configured to convert the coding values of the secondary compression map into representative values of a plurality of blocks divided from a screen by using the reference value, convert the difference values of the primary compression maps into compensation values corresponding to pixels of a corresponding block by using the representative values for each block, and provide the compensation value for each pixel; and

a defect compensation unit configured to receive display data and the compensation value for each pixel, compensate for the display data by using a compensation equation in which the compensation value has been applied to a coefficient value, and output the display data that has been compensated for.

20. The display driving apparatus of claim 19 , wherein the compensation value generation unit

generates the representative values by decoding the coding values subjected to differential coding by using the reference value, and

generates the compensation values corresponding to the pixels of the block by adding the difference value to each of the representative values.