A transmission apparatus comprising: a dynamic range conversion unit configured to obtain high dynamic range transmission video data by performing dynamic range conversion on standard dynamic range transmission video data on the basis of conversion information for converting a value of conversion data in accordance with a standard dynamic range photoelectric conversion characteristic into a value of conversion data in accordance with a high dynamic range photoelectric conversion characteristic, the standard dynamic range transmission video data being obtained by performing, on standard dynamic range video data, photoelectric conversion in accordance with the standard dynamic range photoelectric conversion characteristic; an encoding unit configured to obtain a video stream by performing encoding processing on the high dynamic range transmission video data; and a transmission unit configured to transmit a container having a predetermined format and including the video stream, wherein the conversion information is of a conversion coefficient, wherein the standard dynamic range transmission video data is converted into a value of conversion data when a first input luminance level is from a branch level to a standard dynamic range maximum level, wherein the branch level indicates a luminance level at which a standard dynamic range opto-electrical transfer function curve and a high dynamic range opto-electrical transfer function curve branch, wherein the standard dynamic range maximum level matches a transmission level of the high dynamic range opto-electrical transfer function at a second input luminance level corresponding to the standard dynamic range maximum level, wherein the conversion coefficient is C, and the input data from the branch level B to a relative maximum level M is converted using the equation: output data = branch level B + input data − branch level B * C a dynamic range conversion unit configured to obtain high dynamic range transmission video data by performing dynamic range conversion on standard dynamic range transmission video data on the basis of conversion information for converting a value of conversion data in accordance with a standard dynamic range photoelectric conversion characteristic into a value of conversion data in accordance with a high dynamic range photoelectric conversion characteristic, the standard dynamic range transmission video data being obtained by performing, on standard dynamic range video data, photoelectric conversion in accordance with the standard dynamic range photoelectric conversion characteristic; an encoding unit configured to obtain a video stream by performing encoding processing on the high dynamic range transmission video data; and a transmission unit configured to transmit a container having a predetermined format and including the video stream, wherein the conversion information is of a conversion coefficient, wherein the standard dynamic range transmission video data is converted into a value of conversion data when a first input luminance level is from a branch level to a standard dynamic range maximum level, wherein the branch level indicates a luminance level at which a standard dynamic range opto-electrical transfer function curve and a high dynamic range opto-electrical transfer function curve branch, wherein the standard dynamic range maximum level matches a transmission level of the high dynamic range opto-electrical transfer function at a second input luminance level corresponding to the standard dynamic range maximum level, wherein the conversion coefficient is C, and the input data from the branch level B to a relative maximum level M is converted using the equation: output data = branch level B + input data − branch level B * C