Display device and transmission processing method for image data signal

1. A display device for displaying, on a display panel having data lines, an image based on input image data including a sequence of pixel data pieces indicating luminance levels corresponding to red, green, and blue of respective pixels, the display device comprising:

a driver configured to apply pixel driving voltages to said data lines per a respective one of horizontal scanning lines; and

a control unit configured to generate a transmission image data signal on the basis of the input image data and transmit the transmission image data signal to the driver, wherein

said control unit includes:

an identical color line detecting unit configured to detect, for each of said horizontal scanning lines, whether or not pixels for one horizontal scanning line have an identical color display state on the basis of said sequence of the pixel data pieces in said input image data so as to generate identical color line data indicating a detecting result;

a representative pixel extracting unit configured to extract, as a representative pixel data pieces group, three pixel data pieces corresponding to red, green, and blue, respectively, from among the sequence of the pixel data pieces;

an error correction coding unit configured to perform an error correction coding process on the sequence of the pixel data pieces to generate a coded data block; and

a transmitting unit configured to generate the transmission image data signal, the transmission image data signal including said identical color line data, the representative pixel data pieces group, and the coded data block, and transmit the transmission image data signal to the driver,

wherein if said identical color line data in the transmission image data signal received indicates the pixels for the one horizontal scanning line not having said identical color display state, said driver converts pixel data pieces obtained by performing an error correction process on said coded data block in the transmission image data signal to respective pixel driving voltages, and

wherein if said identical color line data indicates the pixels for the one horizontal scanning line having said identical color display state, said driver converts, without performing said error correction process on said coded data block, the pixel data pieces contained in the representative pixel data pieces group in the transmission image data signal to the respective pixel driving voltages.

2. The display device according to claim 1 , wherein

the control unit includes an interleaving unit for performing an interleaving process on the coded data block,

the driver includes: an error correction circuit for performing the error correction process; and a deinterleaving circuit for performing a deinterleaving process, and

the error correction circuit and the deinterleaving circuit are set in an operation stopped state when the identical color line data indicates the pixels for the one horizontal scanning line having the identical color display state.

3. The display device according to claim 1 , wherein

the driver includes a register for keeping the representative pixel data pieces group, and

if the identical color line data indicates the pixels for the one horizontal scanning line having the identical color display state, the register repeatedly reads out the representative pixel data pieces group for the one horizontal scanning line.

4. The display device according to claim 1 , wherein

the control unit transmits, to the driver, in the transmission image data signal, error check data obtained by performing an error detection coding process on a data sequence constituted by the identical color line data and the representative pixel data pieces group,

the driver includes an error detecting unit for performing an error detection process on a data sequence constituted by the identical color line data and the representative pixel data pieces group on the basis of the error check data contained in the transmission image data signal,

if an error is detected by the error detection process or the identical color line data indicates the pixels for the one horizontal scanning line not having the identical color display state, the driver converts the pixel data pieces obtained by performing the error correction process on the coded data block in the transmission image data signal to the respective pixel driving voltages, and

if no error is detected by the error detection process and the identical color line data indicates the pixels for the one horizontal scanning line having the identical color display state, the driver converts the pixel data pieces contained in the representative pixel data pieces group in the transmission image data signal to the respective pixel driving voltages.

5. The display device according to claim 1 , wherein

in a high-definition mode, the identical color line detecting unit generates the identical color line data on the basis of the sequence of the pixel data pieces in the input image data, and

in a low power consumption mode, the identical color line detecting unit: sets, for each horizontal scanning line, a color most frequent among colors expressed by the respective pixels as a reference color on the basis of the input image data; determines, for each of the pixels, a color difference between the reference color and the color expressed by the pixel; and generates, if the color difference falls within a predetermined range, the identical color line data on the basis of the input image data having undergone correction of replacing luminance levels of the pixel data pieces for red, green, and blue color components corresponding to the pixel with luminance levels for red, green, and blue color components in the reference color, respectively.

6. The display device according to claim 5 , wherein in the low power consumption mode, if there are a plurality of most frequent colors among the colors expressed by the pixels for one horizontal scanning line, an average color of the pixels for one horizontal scanning line is set as the reference color.

7. A transmission processing method for an image data signal in a display device for displaying, on a display panel, an image based on input image data including a sequence of pixel data pieces indicating luminance levels corresponding to red, green, and blue of respective pixels, the method comprising:

a first step of detecting, for each of horizontal scanning lines, whether or not pixels for one horizontal scanning line have an identical color display state on the basis of said sequence of the pixel data pieces in said input image data so as to generate identical color line data indicating a detecting result;

a second step of extracting, as a representative pixel data pieces group, three pixel data pieces corresponding to red, green, and blue, respectively, from among the sequence of the pixel data pieces;

a third step of performing an error correction coding process on the sequence of the pixel data pieces to generate a coded data block;

a fourth step of generating a transmission image data signal including said identical color line data, the representative pixel data pieces group, and the coded data block;

a fifth step of determining whether said identical color line data in the transmission image data signal indicates the pixels for the one horizontal scanning line having said identical color display state or the pixels for the one horizontal scanning line not having said identical color display state; and

a sixth step of converting, if said identical color line data indicates the pixels for the one horizontal scanning line not having said identical color display state, pixel data pieces obtained by performing an error correction process on the coded data block in the transmission image data signal to respective pixel driving voltages and applying the respective pixel driving voltages to the display panel or converting, if said identical color line data indicates the pixels for the one horizontal scanning line having said identical color display state, the pixel data pieces contained in the representative pixel data pieces group in the transmission image data signal, without performing said error correction process on said coded data block, to the respective pixel driving voltages and applying the respective pixel driving voltages to the display panel.

8. The transmission processing method for an image data signal according to claim 7 , wherein

in the second step, an interleaving process is performed on the coded data block, and

in the sixth step, if the identical color line data indicates the pixels for the one horizontal scanning line not having the identical color display state, a deinterleaving process and the error correction process are performed on the coded data block in the transmission image data signal.

9. The transmission processing method for an image data signal according to claim 7 , wherein in the sixth step, if the identical color line data indicates the pixels for the one horizontal scanning line having the identical color display state, the representative pixel data pieces group is kept in a register, and the representative pixel data pieces group is repeatedly read out from the register for the one horizontal scanning line.

10. The transmission processing method for an image data signal according to claim 7 , wherein

in the fourth step, error check data obtained by performing an error detection coding process on a data sequence constituted by the identical color line data and the representative pixel data pieces group is included in the generated transmission image data signal,

in the sixth step, if an error is detected as a result of an error detection process performed on the data sequence constituted by the identical color line data and the representative pixel data pieces group on the basis of the error check data contained in the transmission image data signal or if the identical color line data indicates the pixels for the one horizontal scanning line not having the identical color display state, the pixel data pieces obtained by performing the error correction process on the coded data block in the transmission image data signal are converted to the respective pixel driving voltages, and if the error is not detected and the identical color line data indicates the pixels for the one horizontal scanning line having the identical color display state, the pixel data pieces contained in the representative pixel data pieces group in the transmission image data signal are converted to the respective pixel driving voltages.

11. The transmission processing method for an image data signal according to claim 7 , wherein

in the first step, in a high-definition mode, the identical color line data is generated on the basis of the sequence of the pixel data pieces in the input image data, and

in a low power consumption mode, a color most frequent among colors expressed by the pixels is set as a reference color for each horizontal scanning line on the basis of the input image data; for each of the pixels, a color difference between the reference color and the color expressed by the pixel is determined; and

if the color difference falls within a predetermined range, the identical color line data is generated on the basis of the input image data having undergone correction of replacing luminance levels of the pixel data pieces for red, green, and blue color components corresponding to the pixel with luminance levels for red, green, and blue color components in the reference color, respectively.

12. The transmission processing method for an image data signal according to claim 11 , wherein in the low power consumption mode, if there are a plurality of most frequent colors among the colors expressed by the pixels for one horizontal scanning line, an average color of the pixels for one horizontal scanning line is set as the reference color.