flowly_mp4/mp4box/
stss.rs

1use byteorder::{BigEndian, WriteBytesExt};
2use serde::Serialize;
3use std::io::Write;
4use std::mem::size_of;
5
6use crate::mp4box::*;
7
8#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
9pub struct StssBox {
10    pub version: u8,
11    pub flags: u32,
12
13    #[serde(skip_serializing)]
14    pub entries: Vec<u32>,
15}
16
17impl StssBox {
18    pub fn get_type(&self) -> BoxType {
19        BoxType::StssBox
20    }
21
22    pub fn get_size(&self) -> u64 {
23        HEADER_SIZE + HEADER_EXT_SIZE + 4 + (4 * self.entries.len() as u64)
24    }
25}
26
27impl Mp4Box for StssBox {
28    const TYPE: BoxType = BoxType::StssBox;
29
30    fn box_size(&self) -> u64 {
31        self.get_size()
32    }
33
34    fn to_json(&self) -> Result<String, Error> {
35        Ok(serde_json::to_string(&self).unwrap())
36    }
37
38    fn summary(&self) -> Result<String, Error> {
39        let s = format!("entries={}", self.entries.len());
40        Ok(s)
41    }
42}
43
44impl BlockReader for StssBox {
45    fn read_block<'a>(reader: &mut impl Reader<'a>) -> Result<Self, Error> {
46        let (version, flags) = read_box_header_ext(reader);
47
48        let entry_size = size_of::<u32>(); // sample_number
49        let entry_count = reader.get_u32();
50        if entry_count as usize > reader.remaining() / entry_size {
51            return Err(Error::InvalidData(
52                "stss entry_count indicates more entries than could fit in the box",
53            ));
54        }
55
56        let mut entries = Vec::with_capacity(entry_count as usize);
57        for _i in 0..entry_count {
58            let sample_number = reader.get_u32();
59            entries.push(sample_number);
60        }
61
62        Ok(StssBox {
63            version,
64            flags,
65            entries,
66        })
67    }
68
69    fn size_hint() -> usize {
70        8
71    }
72}
73
74impl<W: Write> WriteBox<&mut W> for StssBox {
75    fn write_box(&self, writer: &mut W) -> Result<u64, Error> {
76        let size = self.box_size();
77        BoxHeader::new(Self::TYPE, size).write(writer)?;
78
79        write_box_header_ext(writer, self.version, self.flags)?;
80
81        writer.write_u32::<BigEndian>(self.entries.len() as u32)?;
82        for sample_number in self.entries.iter() {
83            writer.write_u32::<BigEndian>(*sample_number)?;
84        }
85
86        Ok(size)
87    }
88}
89
90#[cfg(test)]
91mod tests {
92    use super::*;
93    use crate::mp4box::BoxHeader;
94
95    #[tokio::test]
96    async fn test_stss() {
97        let src_box = StssBox {
98            version: 0,
99            flags: 0,
100            entries: vec![1, 61, 121, 181, 241, 301, 361, 421, 481],
101        };
102        let mut buf = Vec::new();
103        src_box.write_box(&mut buf).unwrap();
104        assert_eq!(buf.len(), src_box.box_size() as usize);
105
106        let mut reader = buf.as_slice();
107        let header = BoxHeader::read(&mut reader, &mut 0).await.unwrap().unwrap();
108        assert_eq!(header.kind, BoxType::StssBox);
109        assert_eq!(src_box.box_size(), header.size);
110
111        let dst_box = StssBox::read_block(&mut reader).unwrap();
112        assert_eq!(src_box, dst_box);
113    }
114}
flowly_mp4/mp4box/stss.rs

flowly_mp4/mp4box/
stss.rs
