A recording medium includes a video stream of a standard-luminance range and a video stream of high-luminance range, which are used selectively in accordance with a playback environment. The recording medium also includes a subtitle stream of the standard-luminance range and a subtitle stream of the high-luminance range, which are used selectively in accordance with the playback environment. A playlist file includes a management region where playback control information relating to a main stream is stored, and includes an extended region. The management region stores first playback control information specifying playing of the video stream of the high-luminance range and the subtitle stream of the high-luminance range in combination. The extended region stores second playback control information specifying playing of the video stream of the standard-luminance range and the subtitle stream of the standard-luminance range in combination.

A recording medium includes a video stream of a standard-luminance range and a video stream of high-luminance range, which are used selectively in accordance with a playback environment. The recording medium also includes a subtitle stream of the standard-luminance range and a subtitle stream of the high-luminance range, which are used selectively in accordance with the playback environment. A playlist file includes a management region where playback control information relating to a main stream is stored, and includes an extended region. The management region stores first playback control information specifying playing of the video stream of the high-luminance range and the subtitle stream of the high-luminance range in combination. The extended region stores second playback control information specifying playing of the video stream of the standard-luminance range and the subtitle stream of the standard-luminance range in combination.

A recording medium includes a video stream of a standard-luminance range and a video stream of high-luminance range, which are used selectively in accordance with a playback environment. The recording medium also includes a subtitle stream of the standard-luminance range and a subtitle stream of the high-luminance range, which are used selectively in accordance with the playback environment. A playlist file includes a management region where playback control information relating to a main stream is stored, and includes an extended region. The management region stores first playback control information specifying playing of the video stream of the high-luminance range and the subtitle stream of the high-luminance range in combination. The extended region stores second playback control information specifying playing of the video stream of the standard-luminance range and the subtitle stream of the standard-luminance range in combination.

A playback device and playback method are provided for reading out and playing content from a recording medium in which are recorded a video stream that is encoded video information, map information, and bitrate information of the video stream. The map information includes playback start time information, start position information, and size information. The playback method includes reading out the map information and the bitrate information, and determining the stipulated data size in accordance with the bitrate information. The playback method also includes acquiring the picture from the video stream based on the result of the determination, and the start position information and the size information included in the map information that has been read out. The method further includes decoding and playing the acquired picture, wherein the stipulated data size differs between 2K resolution of the video stream and 4K resolution of the video stream.

A recording medium is provided in which are recorded a video stream that is encoded video information, map information, and bitrate information of the video stream. The map information includes playback start time information of a picture that is independently decodable, start position information indicating a data start position of the picture, and size information indicating a data size of a section where the picture is recorded, based on a predetermined stipulated data size, which differs in accordance with the bitrate information. The size information indicates a data size based on a first stipulated data size, where the bitrate information indicates a bitrate larger than a predetermined value, and indicates a data size based on a second stipulated data size that is smaller than the first stipulated data size, where the bitrate information indicates a bitrate equal to or smaller than the predetermined value.

A playback device is provided that reads out and plays content from a recording medium, in which are recorded a video stream that is encoded video information, map information, and bitrate information of the video stream. The map information includes playback start time information, start position information, and size information. The playback device includes a readout unit that reads out the map information and the bitrate information, a determining unit that determines the stipulated data size indicated by the size information included in the map information, an acquisition unit that acquires the picture from the video stream based on the result of the determination, and a video playback unit that decodes and plays the acquired picture.

A playback method is provided for reading out and playing streams from a recording medium. Recorded in the recording medium are a stream file including a first luminance video expressed by luminance of a first dynamic range, and a second luminance video expressed by luminance of a second dynamic range that is broader than the first dynamic range; a playlist file for controlling playback of the stream file; and a number of elementary streams. The playback method includes when playing the first luminance video, reading out any one of the elementary streams listed in the first combination information of the playlist file, and playing at the same time with the first luminance video; and when playing the second luminance video, reading out any one of the elementary streams listed in the second combination information of the playlist file, and playing at the same time with the second luminance video.

Methods, systems, and devices secure content in memory. The content includes a lock that prohibits reading the content from memory. Prior to expiration of the lock the content cannot be read from the memory. However, a preview option allows at least a portion of the content to be accessed. The preview option provides a preview of the content. At expiration, the content is readable.

Provided is a process of dynamically creating a personalized workout video for a user. The process, including: obtaining a collection of workout video blocks; retrieving a user profile attribute from a user profile, the user profile attribute including a fitness goal or exercise constraint; selecting a first workout video block from the collection based on both the fitness goal or the exercise constraint and an intensity level or body-region grouping of the selected first workout video block; sending the first workout video block to a user device of the user; receiving after beginning to sending the first workout video block; selecting a second workout video block from the collection based on the feedback, the intensity of the second workout video block, and a body-region grouping of the second video block; and beginning to send the second workout video block, with one or more processors, to the user device.

Provided is a process of dynamically creating a personalized workout video for a user. The process, including: obtaining a collection of workout video blocks; retrieving a user profile attribute from a user profile, the user profile attribute including a fitness goal or exercise constraint; selecting a first workout video block from the collection based on both the fitness goal or the exercise constraint and an intensity level or body-region grouping of the selected first workout video block; sending the first workout video block to a user device of the user; receiving after beginning to sending the first workout video block; selecting a second workout video block from the collection based on the feedback, the intensity of the second workout video block, and a body-region grouping of the second video block; and beginning to send the second workout video block, with one or more processors, to the user device.