scuffle-mp4 0.1.5

A pure Rust MP4 parser and writer.
Documentation
use std::io;

use bytes::{Buf, Bytes};
use scuffle_av1::seq::SequenceHeaderObu;
use scuffle_av1::{ObuHeader, ObuType};
use scuffle_bytes_util::BytesCursorExt;

use super::av1c::Av1C;
use super::btrt::Btrt;
use super::stsd::{SampleEntry, VisualSampleEntry};
use crate::boxes::DynBox;
use crate::boxes::header::BoxHeader;
use crate::boxes::traits::BoxType;
use crate::codec::VideoCodec;

#[derive(Debug, Clone, PartialEq)]
/// AV1 Codec Box
/// <https://aomediacodec.github.io/av1-isobmff/#av1sampleentry-section>
pub struct Av01 {
    pub header: BoxHeader,
    pub visual_sample_entry: SampleEntry<VisualSampleEntry>,
    pub av1c: Av1C,
    pub btrt: Option<Btrt>,
    pub unknown: Vec<DynBox>,
}

impl Av01 {
    pub fn new(visual_sample_entry: SampleEntry<VisualSampleEntry>, av1c: Av1C, btrt: Option<Btrt>) -> Self {
        Self {
            header: BoxHeader::new(Self::NAME),
            visual_sample_entry,
            av1c,
            btrt,
            unknown: Vec::new(),
        }
    }

    pub fn codec(&self) -> io::Result<VideoCodec> {
        let mut cursor = io::Cursor::new(self.av1c.av1_config.config_obu.clone());
        let header = ObuHeader::parse(&mut cursor)?;

        let data = cursor.extract_bytes(header.size.unwrap_or(cursor.remaining() as u64) as usize)?;

        if header.obu_type != ObuType::SequenceHeader {
            return Err(io::Error::new(
                io::ErrorKind::InvalidData,
                "av1c box is missing sequence header",
            ));
        }

        let seq_obu = SequenceHeaderObu::parse(header, &mut io::Cursor::new(data))?;
        let op_point = &seq_obu.operating_points[0];

        Ok(VideoCodec::Av1 {
            profile: seq_obu.seq_profile,
            level: op_point.seq_level_idx,
            tier: op_point.seq_tier,
            depth: seq_obu.color_config.bit_depth as u8,
            monochrome: seq_obu.color_config.mono_chrome,
            sub_sampling_x: seq_obu.color_config.subsampling_x,
            sub_sampling_y: seq_obu.color_config.subsampling_y,
            color_primaries: seq_obu.color_config.color_primaries,
            transfer_characteristics: seq_obu.color_config.transfer_characteristics,
            matrix_coefficients: seq_obu.color_config.matrix_coefficients,
            full_range_flag: seq_obu.color_config.full_color_range,
        })
    }
}

impl BoxType for Av01 {
    const NAME: [u8; 4] = *b"av01";

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

        let mut visual_sample_entry = SampleEntry::<VisualSampleEntry>::demux(&mut reader)?;

        let mut av1c = None;
        let mut btrt = None;
        let mut unknown = Vec::new();

        while reader.has_remaining() {
            let dyn_box = DynBox::demux(&mut reader)?;
            match dyn_box {
                DynBox::Av1C(b) => {
                    av1c = Some(b);
                }
                DynBox::Btrt(b) => {
                    btrt = Some(b);
                }
                DynBox::Clap(b) => {
                    visual_sample_entry.extension.clap = Some(*b);
                }
                DynBox::Pasp(b) => {
                    visual_sample_entry.extension.pasp = Some(*b);
                }
                DynBox::Colr(b) => {
                    visual_sample_entry.extension.colr = Some(*b);
                }
                _ => {
                    unknown.push(dyn_box);
                }
            }
        }

        let av1c = av1c.ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "trak box is missing tkhd box"))?;

        Ok(Self {
            header,
            visual_sample_entry,
            av1c: *av1c,
            btrt: btrt.map(|b| *b),
            unknown,
        })
    }

    fn primitive_size(&self) -> u64 {
        self.visual_sample_entry.size()
            + self.av1c.size()
            + self.btrt.as_ref().map(|b| b.size()).unwrap_or(0)
            + self.unknown.iter().map(|b| b.size()).sum::<u64>()
    }

    fn primitive_mux<T: io::Write>(&self, writer: &mut T) -> io::Result<()> {
        self.visual_sample_entry.mux(writer)?;
        self.av1c.mux(writer)?;
        if let Some(btrt) = &self.btrt {
            btrt.mux(writer)?;
        }
        for unknown in &self.unknown {
            unknown.mux(writer)?;
        }
        Ok(())
    }
}