scuffle_mp4/boxes/types/
hdlr.rs

use std::io::{
    Read, {self},
};

use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
use bytes::Bytes;

use crate::boxes::header::{BoxHeader, FullBoxHeader};
use crate::boxes::traits::BoxType;

#[derive(Debug, Clone, PartialEq)]
/// Handler Reference Box
/// ISO/IEC 14496-12:2022(E) - 8.4.3
pub struct Hdlr {
    pub header: FullBoxHeader,
    pub pre_defined: u32,
    pub handler_type: HandlerType,
    pub reserved: [u32; 3],
    pub name: String,
}

impl Hdlr {
    pub fn new(handler_type: HandlerType, name: String) -> Self {
        Self {
            header: FullBoxHeader::new(Self::NAME, 0, 0),
            pre_defined: 0,
            handler_type,
            reserved: [0; 3],
            name,
        }
    }
}

#[derive(Debug, Clone, PartialEq)]
/// The handler type indicates the media type of the media in the track.
/// The handler type is a 32-bit value composed of a 4-character code.
pub enum HandlerType {
    Vide,
    Soun,
    Hint,
    Meta,
    Unknown([u8; 4]),
}

impl HandlerType {
    pub fn to_bytes(&self) -> [u8; 4] {
        match self {
            Self::Vide => *b"vide",
            Self::Soun => *b"soun",
            Self::Hint => *b"hint",
            Self::Meta => *b"meta",
            Self::Unknown(b) => *b,
        }
    }
}

impl From<[u8; 4]> for HandlerType {
    fn from(v: [u8; 4]) -> Self {
        match &v {
            b"vide" => Self::Vide,
            b"soun" => Self::Soun,
            b"hint" => Self::Hint,
            b"meta" => Self::Meta,
            _ => Self::Unknown(v),
        }
    }
}

impl BoxType for Hdlr {
    const NAME: [u8; 4] = *b"hdlr";

    fn demux(header: BoxHeader, data: Bytes) -> io::Result<Self> {
        let mut reader = io::Cursor::new(data);

        let header = FullBoxHeader::demux(header, &mut reader)?;

        let pre_defined = reader.read_u32::<BigEndian>()?;

        let mut handler_type = [0; 4];
        reader.read_exact(&mut handler_type)?;

        let mut reserved = [0; 3];
        for v in reserved.iter_mut() {
            *v = reader.read_u32::<BigEndian>()?;
        }

        let mut name = String::new();
        loop {
            let c = reader.read_u8()?;
            if c == 0 {
                break;
            }

            name.push(c as char);
        }

        Ok(Self {
            header,
            pre_defined,
            handler_type: handler_type.into(),
            reserved,
            name,
        })
    }

    fn primitive_size(&self) -> u64 {
        self.header.size()
        + 4 // pre_defined
        + 4 // handler_type
        + 3 * 4 // reserved
        + self.name.len() as u64 + 1 // name + null terminator
    }

    fn primitive_mux<T: io::Write>(&self, writer: &mut T) -> io::Result<()> {
        self.header.mux(writer)?;

        writer.write_u32::<BigEndian>(self.pre_defined)?;

        writer.write_all(&self.handler_type.to_bytes())?;

        for v in self.reserved.iter() {
            writer.write_u32::<BigEndian>(*v)?;
        }

        writer.write_all(self.name.as_bytes())?;
        writer.write_u8(0)?;

        Ok(())
    }

    fn validate(&self) -> io::Result<()> {
        if self.header.version != 0 {
            return Err(io::Error::new(io::ErrorKind::InvalidData, "hdlr version must be 0"));
        }

        if self.header.flags != 0 {
            return Err(io::Error::new(io::ErrorKind::InvalidData, "hdlr flags must be 0"));
        }

        if self.reserved != [0; 3] {
            return Err(io::Error::new(io::ErrorKind::InvalidData, "hdlr reserved must be 0"));
        }

        if self.pre_defined != 0 {
            return Err(io::Error::new(io::ErrorKind::InvalidData, "hdlr pre_defined must be 0"));
        }

        Ok(())
    }
}
scuffle_mp4/boxes/types/hdlr.rs

scuffle_mp4/boxes/types/
hdlr.rs
