mp4/mp4box/
mehd.rs

1use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
2use serde::Serialize;
3use std::io::{Read, Seek, Write};
4
5use crate::mp4box::*;
6
7#[derive(Debug, Clone, PartialEq, Eq, Serialize, Default)]
8pub struct MehdBox {
9    pub version: u8,
10    pub flags: u32,
11    pub fragment_duration: u64,
12}
13
14impl MehdBox {
15    pub fn get_type(&self) -> BoxType {
16        BoxType::MehdBox
17    }
18
19    pub fn get_size(&self) -> u64 {
20        let mut size = HEADER_SIZE + HEADER_EXT_SIZE;
21
22        if self.version == 1 {
23            size += 8;
24        } else if self.version == 0 {
25            size += 4;
26        }
27        size
28    }
29}
30
31impl Mp4Box for MehdBox {
32    fn box_type(&self) -> BoxType {
33        self.get_type()
34    }
35
36    fn box_size(&self) -> u64 {
37        self.get_size()
38    }
39
40    fn to_json(&self) -> Result<String> {
41        Ok(serde_json::to_string(&self).unwrap())
42    }
43
44    fn summary(&self) -> Result<String> {
45        let s = format!("fragment_duration={}", self.fragment_duration);
46        Ok(s)
47    }
48}
49
50impl<R: Read + Seek> ReadBox<&mut R> for MehdBox {
51    fn read_box(reader: &mut R, size: u64) -> Result<Self> {
52        let start = box_start(reader)?;
53
54        let (version, flags) = read_box_header_ext(reader)?;
55
56        let fragment_duration = if version == 1 {
57            reader.read_u64::<BigEndian>()?
58        } else if version == 0 {
59            reader.read_u32::<BigEndian>()? as u64
60        } else {
61            return Err(Error::InvalidData("version must be 0 or 1"));
62        };
63        skip_bytes_to(reader, start + size)?;
64
65        Ok(MehdBox {
66            version,
67            flags,
68            fragment_duration,
69        })
70    }
71}
72
73impl<W: Write> WriteBox<&mut W> for MehdBox {
74    fn write_box(&self, writer: &mut W) -> Result<u64> {
75        let size = self.box_size();
76        BoxHeader::new(self.box_type(), size).write(writer)?;
77
78        write_box_header_ext(writer, self.version, self.flags)?;
79
80        if self.version == 1 {
81            writer.write_u64::<BigEndian>(self.fragment_duration)?;
82        } else if self.version == 0 {
83            writer.write_u32::<BigEndian>(self.fragment_duration as u32)?;
84        } else {
85            return Err(Error::InvalidData("version must be 0 or 1"));
86        }
87
88        Ok(size)
89    }
90}
91
92#[cfg(test)]
93mod tests {
94    use super::*;
95    use crate::mp4box::BoxHeader;
96    use std::io::Cursor;
97
98    #[test]
99    fn test_mehd32() {
100        let src_box = MehdBox {
101            version: 0,
102            flags: 0,
103            fragment_duration: 32,
104        };
105        let mut buf = Vec::new();
106        src_box.write_box(&mut buf).unwrap();
107        assert_eq!(buf.len(), src_box.box_size() as usize);
108
109        let mut reader = Cursor::new(&buf);
110        let header = BoxHeader::read(&mut reader).unwrap();
111        assert_eq!(header.name, BoxType::MehdBox);
112        assert_eq!(src_box.box_size(), header.size);
113
114        let dst_box = MehdBox::read_box(&mut reader, header.size).unwrap();
115        assert_eq!(src_box, dst_box);
116    }
117
118    #[test]
119    fn test_mehd64() {
120        let src_box = MehdBox {
121            version: 0,
122            flags: 0,
123            fragment_duration: 30439936,
124        };
125        let mut buf = Vec::new();
126        src_box.write_box(&mut buf).unwrap();
127        assert_eq!(buf.len(), src_box.box_size() as usize);
128
129        let mut reader = Cursor::new(&buf);
130        let header = BoxHeader::read(&mut reader).unwrap();
131        assert_eq!(header.name, BoxType::MehdBox);
132        assert_eq!(src_box.box_size(), header.size);
133
134        let dst_box = MehdBox::read_box(&mut reader, header.size).unwrap();
135        assert_eq!(src_box, dst_box);
136    }
137}
mp4/mp4box/mehd.rs

mp4/mp4box/
mehd.rs
