isobmff/boxes/
sub_tracks.rs

1use crate::{FullBoxHeader, IsoBox};
2
3/// Sub track box
4///
5/// ISO/IEC 14496-12 - 8.14.3
6#[derive(IsoBox, Debug, PartialEq, Eq)]
7#[iso_box(box_type = b"strk", crate_path = crate)]
8pub struct SubTrackBox {
9    /// The contained [`SubTrackInformationBox`]. (mandatory)
10    #[iso_box(nested_box)]
11    pub stri: SubTrackInformationBox,
12    /// The contained [`SubTrackDefinitionBox`]. (optional)
13    ///
14    /// According to the official specification this is mandatory, but
15    /// there is one official sample file in which it is not present.
16    /// See <https://github.com/MPEGGroup/FileFormatConformance/issues/155>.
17    #[iso_box(nested_box(collect))]
18    pub strd: Option<SubTrackDefinitionBox>,
19}
20
21/// Sub track information box
22///
23/// ISO/IEC 14496-12 - 8.14.4
24#[derive(IsoBox, Debug, PartialEq, Eq)]
25#[iso_box(box_type = b"stri", crate_path = crate)]
26pub struct SubTrackInformationBox {
27    /// The full box header.
28    pub full_header: FullBoxHeader,
29    /// An integer that specifies a group or collection of tracks and/or sub tracks. If this field
30    /// is 0 (default value), then there is no information on whether the sub track can be used for switching
31    /// during playing or streaming. If this integer is not 0 it shall be the same for tracks and/or sub tracks
32    /// that can be used for switching between each other. Tracks that belong to the same switch group
33    /// shall belong to the same alternate group. A switch group may have only one member.
34    pub switch_group: i16,
35    /// An integer that specifies a group or collection of tracks and/or sub tracks. If this
36    /// field is 0 (default value), then there is no information on possible relations to other tracks/sub-
37    /// tracks. If this field is not 0, it should be the same for tracks/sub-tracks that contain alternate data
38    /// for one another and different for tracks/sub-tracks belonging to different such groups. Only one
39    /// track/sub-track within an alternate group should be played or streamed at any one time.
40    pub alternate_group: i16,
41    /// An integer. A non-zero value uniquely identifies the sub track locally within the track.
42    /// A zero value (default) means that sub_track_ID is not assigned.
43    pub sub_track_id: u32,
44    /// A list, to the end of the box, of attributes. The attributes in this list should be used as
45    /// descriptions of sub tracks or differentiating criteria for tracks and sub tracks in the same alternate
46    /// or switch group.
47    #[iso_box(repeated)]
48    pub attribute_list: Vec<u32>,
49}
50
51/// Sub track definition box
52///
53/// ISO/IEC 14496-12 - 8.14.5
54#[derive(IsoBox, Debug, PartialEq, Eq)]
55#[iso_box(box_type = b"strd", crate_path = crate)]
56pub struct SubTrackDefinitionBox {
57    /// The contained [`SubTrackSampleGroupBox`]es. (any quantity)
58    #[iso_box(nested_box(collect))]
59    pub stsg: Vec<SubTrackSampleGroupBox>,
60}
61
62/// Sub track sample group box
63///
64/// ISO/IEC 14496-12 - 8.14.6
65#[derive(IsoBox, Debug, PartialEq, Eq)]
66#[iso_box(box_type = b"stsg", crate_path = crate)]
67pub struct SubTrackSampleGroupBox {
68    /// The full box header.
69    pub full_header: FullBoxHeader,
70    /// An integer that identifies the sample grouping. The value shall be the same as in the
71    /// corresponding SampleToGroupBox and [`SampleGroupDescriptionBox`](super::SampleGroupDescriptionBox).
72    pub grouping_type: [u8; 4],
73    /// Counts the number of sample groups listed in this box.
74    pub item_count: u16,
75    /// An integer that gives the index of the sample group entry which describes
76    /// the samples in the group.
77    #[iso_box(repeated)]
78    pub group_description_index: Vec<u32>,
79}
isobmff/boxes/sub_tracks.rs

isobmff/boxes/
sub_tracks.rs
