Transmission apparatus, transmission method, reception apparatus, and reception method

1. A transmission apparatus comprising:

processing circuitry configured to

obtain first dynamic range transmission video data by applying a first photoelectric conversion characteristic to first dynamic range video data,

convert the first dynamic range transmission video data to second dynamic range transmission video data based on conversion information for converting a value of conversion data in accordance with the first photoelectric conversion characteristic into a value of conversion data in accordance with a second photoelectric conversion characteristic,

obtain a video stream by performing encoding processing on the second dynamic range transmission video data, and

insert, into the video stream, the conversion information used to convert the first dynamic range transmission video data to the second dynamic range transmission video data; and

a transmitter configured to transmit the video stream including the conversion information and to transmit metadata including information indicating an electro-optical transfer function corresponding to the second photoelectric conversion characteristic.

2. The transmission apparatus according to claim 1 , wherein a first dynamic range of the first dynamic range transmission video data is a standard dynamic range, and a second dynamic range of the second dynamic range transmission video data is a high dynamic range.

3. The transmission apparatus according to claim 1 , wherein the processing circuitry is further configured to:

obtain the second dynamic range transmission video data by converting from a color space to a luminance and chrominance domain.

4. The transmission apparatus according to claim 1 , wherein the metadata includes information indicating a dynamic range of the video stream.

5. The transmission apparatus according to claim 1 , wherein the metadata further includes information indicating color primaries for the video stream.

6. The transmission apparatus according to claim 5 , wherein the metadata further includes information indicating color matrix coefficient for the video stream.

7. The transmission apparatus according to claim 1 , wherein the

metadata includes information indicating an original dynamic range of the video stream.

8. The transmission apparatus according to claim 1 , wherein the conversion information is a conversion coefficient.

9. The transmission apparatus according to claim 1 , wherein the conversion information is a conversion table.

10. The transmission apparatus according to claim 1 , wherein the conversion information comprises a data structure, including the metadata indicating the electro-optical transfer function corresponding to the second photoelectric conversion characteristic as one of plural elements of the data structure.

11. A transmission method comprising:

obtaining first dynamic range transmission video data by applying a first photoelectric conversion characteristic to first dynamic range video data;

converting the first dynamic range transmission video data to second dynamic range transmission video data based on conversion information for converting a value of conversion data in accordance with the first photoelectric conversion characteristic into a value of conversion data in accordance with a second photoelectric conversion characteristic;

obtaining a video stream by performing encoding processing on the second dynamic range transmission video data;

inserting, into the video stream, the conversion information used to convert the first dynamic range transmission video data to the second dynamic range transmission video data; and

transmitting via a transmitter, the video stream including the conversion information and transmitting metadata including information indicating an electro-optical transfer function corresponding to the second photoelectric conversion characteristic.

12. A reception apparatus comprising:

a receiver configured to receive a video stream of encoded second dynamic range transmission video data, the video stream further including conversion information used to convert first dynamic range transmission video data having a first photoelectric conversion characteristic to the second dynamic range transmission video data having a second photoelectric conversion characteristic, and to receive metadata including information indicating an electro-optical transfer function corresponding to the second photoelectric conversion characteristic; and

processing circuitry configured to,

obtain the second dynamic range transmission video data by performing decoding processing on the video stream,

extract the conversion information from the video stream,

obtain the first dynamic range transmission video data by performing dynamic range conversion on the second dynamic range transmission video data based on the conversion information extracted from the video stream, and

display first dynamic range video data by performing, on the first dynamic range transmission video data, electro-optical conversion in accordance with a first electro-optical conversion characteristic.

13. The reception apparatus according to claim 12 ,

wherein the second dynamic range transmission video data is obtained by performing the dynamic range conversion on the first dynamic range transmission video data based on the conversion information for converting a value of conversion data in accordance with the first photoelectric conversion characteristic into a value of conversion data in accordance with the second photoelectric conversion characteristic, the first dynamic range transmission video data being obtained by performing, on first dynamic range video data, photoelectric conversion in accordance with the first photoelectric conversion characteristic.

14. The reception apparatus according to claim 13 , wherein the second dynamic range transmission video data is obtained by converting from a color space to a luminance and chrominance domain.

15. The reception apparatus according to claim 12 , wherein a first dynamic range of the first dynamic range transmission video data is a standard dynamic range and a second dynamic range of the second dynamic range transmission video data is a high dynamic range.

16. The reception apparatus according to claim 12 , wherein the metadata includes information indicating a dynamic range of the video stream.

17. The reception apparatus according to claim 16 , wherein the metadata further includes information indicating color primaries for the video stream.

18. The reception apparatus according to claim 17 , wherein the metadata further includes information indicating color matrix coefficient for the video stream.

19. The reception apparatus according to claim 12 , wherein the metadata includes information indicating an original dynamic range of the video stream.

20. A reception method comprising:

receiving, by a receiver, a video stream of encoded second dynamic range transmission video data, the video stream further including conversion information used to convert first dynamic range transmission video data having a first photoelectric conversion characteristic to the second dynamic range transmission video data having a second photoelectric conversion characteristic, and receiving metadata including information indicating an electro-optical transfer function corresponding to the second photoelectric conversion characteristic;

obtaining the second dynamic range transmission video data by performing decoding processing on the encoded second dynamic range transmission video data included in the video stream;

extracting the conversion information from the video stream,

obtaining the first dynamic range transmission video data by performing dynamic range conversion on the second dynamic range transmission video data based on the conversion information extracted from the video stream; and

displaying first dynamic range video data by performing, on the first dynamic range transmission video data, electro-optical conversion in accordance with a first electro-optical conversion characteristic.