Production apparatus and content distribution system

1. A production apparatus for producing a distribution content including distribution video data, the production apparatus comprising:

an original video acquisition unit configured to acquire original video data;

a distribution video acquisition unit configured to acquire the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

a difference calculation unit configured to calculate a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

a shift amount generation unit configured to generate shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated by the difference calculation unit;

a reduction unit configured to generate difference data by reducing a bit length of the difference calculated by the difference calculation unit in accordance with the shift amount determined by the shift amount generation unit for the frame being processed; and

an output unit configured to output the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced by the reduction unit,

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined by the shift amount generation unit, and

the output unit performs the output by writing the distribution content on a recording medium and writing the difference data and the shift amount data on the recording medium in association with the distribution content.

2. The production apparatus of claim 1 , wherein

the shift amount generation unit generates the shift amount in accordance with a count of consecutive zeros in the one or more most significant bits other than the sign bit.

3. The production apparatus of claim 1 , wherein

the shift amount generation unit generates one value for the shift amount for each frame.

4. A production apparatus for producing a distribution content including distribution video data, the production apparatus comprising:

an original video acquisition unit configured to acquire original video data;

a distribution video acquisition unit configured to acquire the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

a difference calculation unit configured to calculate a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

a shift amount generation unit configured to generate shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated by the difference calculation unit;

a reduction unit configured to generate difference data by reducing a bit length of the difference calculated by the difference calculation unit in accordance with the shift amount determined by the shift amount generation unit for the frame being processed; and

an output unit configured to output the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced by the reduction unit,

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined by the shift amount generation unit, and

the output unit performs the output by writing the distribution content on a recording medium and transmitting the difference data and the shift amount data to a server apparatus in association with the distribution content.

5. The production apparatus of claim 4 , wherein

the shift amount generation unit generates the shift amount in accordance with a count of consecutive zeros in the one or more most significant bits other than the sign bit.

6. The production apparatus of claim 4 , wherein

the shift amount generation unit generates one value for the shift amount for each frame.

7. A production method used in a production apparatus for producing a distribution content including distribution video data, the production method comprising the steps of:

(a) acquiring original video data;

(b) acquiring the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

(c) calculating a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

(d) generating shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated in step (c);

(e) generating difference data by reducing a bit length of the difference calculated in step (c) in accordance with the shift amount, determined in step (d), for the frame being processed; and

(f) outputting the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced in step (e), and

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined in step (d).

8. A non-transitory computer-readable recording medium having recorded thereon a computer program used in a production apparatus for producing a distribution content including distribution video data,

the computer program causing a computer to perform a method comprising the steps of:

(a) acquiring original video data;

(b) acquiring the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

(c) calculating a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

(d) generating shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated in step (c);

(e) generating difference data by reducing a bit length of the difference calculated in step (c) in accordance with the shift amount, determined in step (d), for the frame being processed; and

(f) outputting the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced in step (e), and

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined in step (d).

9. An integrated circuit constituting a production apparatus for producing a distribution content including distribution video data, the integrated circuit comprising:

an original video acquisition unit configured to acquire original video data;

a distribution video acquisition unit configured to acquire the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

a difference calculation unit configured to calculate a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

a shift amount generation unit configured to generate shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated by the difference calculation unit;

a reduction unit configured to generate difference data by reducing a bit length of the difference calculated by the difference calculation unit in accordance with the shift amount determined by the shift amount generation unit for the frame being processed; and

an output unit configured to output the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced by the reduction unit,

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined by the shift amount generation unit, and

the output unit performs the output by writing the distribution content on a recording medium and writing the difference data and the shift amount data on the recording medium in association with the distribution content.

10. A content distribution system including a production apparatus and a playback apparatus, the production apparatus being for producing a distribution content including distribution video data, and the playback apparatus being for playing back the distribution content,

the production apparatus comprising:

an original video acquisition unit configured to acquire original video data;

a distribution video acquisition unit configured to acquire the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

a difference calculation unit configured to calculate a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

a shift amount generation unit configured to generate shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated by the difference calculation unit;

a reduction unit configured to generate difference data by reducing a bit length of the difference calculated by the difference calculation unit in accordance with the shift amount determined by the shift amount generation unit for the frame being processed; and

an output unit configured to output the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced by the reduction unit, and

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined by the shift amount generation unit,

the playback apparatus comprising:

an acquisition unit configured to acquire the difference data and the shift amount data;

a combination unit configured to combine the distribution video data with the acquired difference data, shifted using the shift amount data, so as to generate playback video data having a gradation equivalent to the original video data; and

a playback unit configured to play back the generated playback video data.

11. An integrated circuit constituting a production apparatus for producing a distribution content including distribution video data, the integrated circuit comprising:

an original video acquisition unit configured to acquire original video data;

a distribution video acquisition unit configured to acquire the distribution video data, the distribution video data having been generated by conversion of the original video data to a lower gradation;

a difference calculation unit configured to calculate a difference between primary color data in the original video data and primary color data in the distribution video data, the original video data and the distribution video data both including a plurality of frames, each frame including a plurality of pixels, each pixel including primary color data for each primary color, and the difference being calculated for each primary color of each pixel of a frame being processed;

a shift amount generation unit configured to generate shift amount data including a shift amount for the frame being processed by determining the shift amount in accordance with a value of one or more most significant bits, other than a sign bit, in the difference calculated by the difference calculation unit;

a reduction unit configured to generate difference data by reducing a bit length of the difference calculated by the difference calculation unit in accordance with the shift amount determined by the shift amount generation unit for the frame being processed; and

an output unit configured to output the difference data and the shift amount data, wherein

the difference data includes a plurality of frames, each frame including a plurality of pixels, each pixel including, for each primary color, the difference whose bit length is reduced by the reduction unit,

the shift amount data includes a plurality of pairs of, in one-to-one correspondence, a frame number uniquely identifying a frame and the shift amount for the frame determined by the shift amount generation unit, and

the output unit performs the output by writing the distribution content on a recording medium and transmitting the difference data and the shift amount data to a server apparatus in association with the distribution content.