File generation device and method, and content playback device and method
The present disclosure relates to a file generation device and a method, and a content playback device, enabling efficient access to arbitrary subsamples within a sample. As indicated by grouping_type=‘sgss’, a subsample sample group (entry) structure is used as an sgpd. mha1 is identification information indicating 3d audio. As indicated by entry_count=3, the sgpd includes three entries. The three entries are defined to be mha1 0, mha1 1, and mha1 2. To assign these meanings of the sgpd to levels, the sgpd entries are linked to leva entries in index order. The present disclosure may be applied to a content playback system equipped with a content server and a content playback device, for example.
1. A file generation device, comprising:
an encoding unit configured to:
encode content corresponding to a first sample group,
wherein the first sample group comprises a plurality of subsamples; and
generate a bit stream corresponding to the encoded content;
a subsample information generation unit configured to:
define the first sample group in a file based on definition flags,
wherein the file includes the generated bit stream;
define a second sample group to a third sample group and the defined first sample group,
wherein the second sample group stores reference information, and
the third sample group includes subsample position information;
group the second sample group, the third sample group, and the defined first sample group, as a fourth sample group;
map the fourth sample group to a level corresponding to a data type of at least one object of the encoded content; and
generate subsample access information to access each of the plurality of subsamples, based on the mapped fourth sample group; and
a file generation unit configured to:
multiplex the subsample access information generated to access the plurality of subsamples; and
generate the file, based on the generated bit stream and the multiplexed subsample access information.
2. The file generation device according to claim 1 , wherein
the plurality of subsamples are tiles that correspond to an image included in the encoded content.
3. The file generation device according to claim 1 , wherein
the plurality of subsamples are 3D audio data that corresponds to the encoded content.
4. The file generation device according to claim 1 , wherein
the encoded content includes an image that is partitioned into a plurality of subsamples.
5. The file generation device according to claim 1 , wherein
the subsample access information comprises a sample group description box, a level assignment box, and a subsegment index box.
6. The file generation device according to claim 1 , wherein
the definition flags define a type of each of the plurality of subsamples,
wherein the type of each of the plurality of subsamples includes one of a NAL unit based subsample, decoding unit based subsample, tile based subsample, CTU row based subsample, or slice based subsample.
7. A file generation method, comprising:
encoding content corresponding to a first sample group,
wherein the first sample group comprises a plurality of subsamples; and
generating a bit stream corresponding to the encoded content;
defining, by a file generation device, the first sample group in a file based on definition flags,
wherein the file includes the generated bit stream;
defining, by the file generation device, a second sample group to a third sample group and the defined first sample group,
wherein the second sample group stores reference information, and the third sample group includes subsample position information;
grouping, by the file generation device, the second sample group, the third sample group, and the defined first sample group, as a fourth sample group;
mapping, by the file generation device, the fourth sample group to a level corresponding to a data type of at least one object of the encoded content; and
generating subsample access information, to access each of the plurality of subsamples, based on the mapped fourth sample group;
multiplexing the subsample access information generated to access the plurality of subsamples; and
generating, by the file generation device, the file based on the generated bit stream and the multiplexed subsample access information.
8. A content playback device, comprising:
an information acquisition unit configured to:
acquire subsample access information, to access a plurality of subsamples in a first sample group, based on a fourth sample group, from a multiplexed file,
wherein, in the multiplexed file, the first sample group is defined based on definition flags,
wherein the multiplexed file includes a bit stream generated by an encode operation on content,
wherein a second sample group is defined to a third sample group and the defined first sample group,
wherein the second sample group stores reference information, and the third sample group includes subsample position information,
wherein the second sample group, the third sample group, and the defined first sample group are grouped as the fourth sample group,
wherein the fourth sample group is mapped to a level corresponding to a data type of at least one object of the encoded content, and
wherein the encoded content is acquired by partition of an image into the plurality of subsamples;
a sample acquisition unit configured to acquire arbitrary subsamples based on the acquired subsample access information; and
a playback unit configured to play back the acquired arbitrary subsamples.
9. The content playback device according to claim 8 , wherein
the plurality of subsamples are tiles that correspond to the image.
10. The content playback device according to claim 8 , wherein
the plurality of subsamples are 3D audio data that corresponds to the encoded content.
11. The content playback device according to claim 8 , further comprising:
a transmission unit configured to transmit the encoded content to a server connected via a network,
wherein the server stores the encoded content.
12. A content playback method, comprising:
acquiring, by a content playback device, subsample access information, to access a plurality of subsamples in a first sample group, based on a fourth sample group, from a multiplexed file,
wherein, in the multiplexed file, the first sample group is defined based on definition flags,
wherein the multiplexed file includes a bit stream generated by encoding content,
wherein a second sample group is defined to a third sample group and the defined first sample group,
wherein the second sample group stores reference information, and the third sample group includes subsample position information,
wherein the second sample group, the third sample group, and the defined first sample group are grouped as the fourth sample group,
wherein the fourth sample group is mapped to a level corresponding to a data type of at least one object of the encoded content, and
wherein the encoded content is acquired by partitioning an image into the plurality of subsamples;
acquiring, by the content playback device, arbitrary subsamples based on the acquired subsample access information; and
playing back, by the content playback device, the acquired arbitrary subsamples.