Video transmission method, video reception method, video transmission apparatus, and video reception apparatus

A video reception method performed by a video reception apparatus including a display, the video reception method comprising:

• receiving a reception signal including, in a time series, first video data having a first luminance dynamic range and second video data having a second luminance dynamic range wider than the first luminance dynamic range,
• wherein, in the reception signal, a signal level corresponding to a luminance value is limited to a value lower than a limit value in an interchangeable region, wherein a shape of a first transfer characteristic curve of the first luminance dynamic range and a shape of a second transfer characteristic curve of the second luminance dynamic range match, in a transition period provided for switching from one of the first video data and the second video data to the other of the first video data and the second video data, and
• the reception signal includes first information for notifying, in a first period immediately after a start of the transition period, switching of a luminance dynamic range,
• the video reception method further comprising:
• switching the luminance dynamic range of the display during a switching allowed time that starts when the first information is obtained, the switching allowed time being a length of time allowed for switching the luminance dynamic range.

A video transmission apparatus, comprising:

• a generator that generates a transmission signal including, in a time series, first video data having a first luminance dynamic range and second video data having a second luminance dynamic range wider than the first luminance dynamic range;
• and
• a transmitter that transmits the transmission signal generated,
• wherein the generator limits a signal level corresponding to a luminance value to a value lower than a limit value in an interchangeable region, wherein a shape of a first transfer characteristic curve of the first luminance dynamic range and a shape of a second transfer characteristic curve of the second luminance dynamic range match, in a transition period provided for switching from one of the first video data and the second video data to the other of the first video data and the second video data.

A video reception apparatus including a display, the video reception apparatus comprising:

• a receiver that receives a reception signal including, in a time series, first video data having a first luminance dynamic range and second video data having a second luminance dynamic range wider than the first luminance dynamic range,
• wherein, in the reception signal, a signal level corresponding to a luminance value is limited to a value lower than a limit value in an interchangeable region, wherein a shape of a first transfer characteristic curve of the first luminance dynamic range and a shape of a second transfer characteristic curve of the second luminance dynamic range match, in a transition period provided for switching from one of the first video data and the second video data to the other of the first video data and the second video data, and
• the reception signal includes first information for notifying, in a first period immediately after a start of the transition period, switching of a luminance dynamic range,
• the video reception apparatus further comprising:
• a display controller that switches the luminance dynamic range of the display during a switching allowed time that starts when the first information is obtained, the switching allowed time being a length of time allowed for switching the luminance dynamic range.