Add Opus and dOps box parsing

Channel mapping table is still TBD

src/mp4box/mod.rs

@@ -85,6 +85,7 @@ pub(crate) mod moov;
 pub(crate) mod mp4a;
 pub(crate) mod mvex;
 pub(crate) mod mvhd;
+pub(crate) mod opus;
 pub(crate) mod smhd;
 pub(crate) mod stbl;
 pub(crate) mod stco;
@@ -238,7 +239,9 @@ boxtype! {
     CovrBox => 0x636f7672,
     DescBox => 0x64657363,
     WideBox => 0x77696465,
-    WaveBox => 0x77617665
+    WaveBox => 0x77617665,
+    OpusBox => 0x4F707573,
+    DopsBox => 0x644F7073
 }
 
 pub trait Mp4Box: Sized {

src/mp4box/opus.rs

@@ -0,0 +1,271 @@
+use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
+use serde::Serialize;
+use std::io::{Read, Seek, Write};
+
+use crate::mp4box::*;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
+pub struct OpusBox {
+    pub data_reference_index: u16,
+    pub channelcount: u16,
+    pub samplesize: u16,
+
+    #[serde(with = "value_u32")]
+    pub samplerate: FixedPointU16,
+    pub dops: DopsBox,
+}
+
+impl Default for OpusBox {
+    fn default() -> Self {
+        Self {
+            data_reference_index: 0,
+            channelcount: 2,
+            samplesize: 16,
+            samplerate: FixedPointU16::new(48000),
+            dops: DopsBox::default(),
+        }
+    }
+}
+
+impl OpusBox {
+    pub fn new(config: &OpusConfig) -> Self {
+        Self {
+            data_reference_index: 1,
+            channelcount: config.chan_conf as u16,
+            samplesize: 16,
+            samplerate: FixedPointU16::new(config.freq_index.freq() as u16),
+            dops: DopsBox::new(config),
+        }
+    }
+
+    pub fn get_type(&self) -> BoxType {
+        BoxType::OpusBox
+    }
+
+    pub fn get_size(&self) -> u64 {
+        let mut size = HEADER_SIZE + 8 + 20;
+        size += self.dops.box_size();
+        size
+    }
+}
+
+impl Mp4Box for OpusBox {
+    fn box_type(&self) -> BoxType {
+        self.get_type()
+    }
+
+    fn box_size(&self) -> u64 {
+        self.get_size()
+    }
+
+    fn to_json(&self) -> Result<String> {
+        Ok(serde_json::to_string(&self).unwrap())
+    }
+
+    fn summary(&self) -> Result<String> {
+        let s = format!(
+            "channel_count={} sample_size={} sample_rate={}",
+            self.channelcount,
+            self.samplesize,
+            self.samplerate.value()
+        );
+        Ok(s)
+    }
+}
+
+impl<R: Read + Seek> ReadBox<&mut R> for OpusBox {
+    fn read_box(reader: &mut R, size: u64) -> Result<Self> {
+        let start = box_start(reader)?;
+
+        reader.read_u32::<BigEndian>()?; // reserved
+        reader.read_u16::<BigEndian>()?; // reserved
+        let data_reference_index = reader.read_u16::<BigEndian>()?;
+        let _version = reader.read_u16::<BigEndian>()?;
+        reader.read_u16::<BigEndian>()?; // reserved
+        reader.read_u32::<BigEndian>()?; // reserved
+        let channelcount = reader.read_u16::<BigEndian>()?;
+        let samplesize = reader.read_u16::<BigEndian>()?;
+        reader.read_u32::<BigEndian>()?; // pre-defined, reserved
+        let samplerate = FixedPointU16::new_raw(reader.read_u32::<BigEndian>()?);
+
+        // read dOps box
+        let header = BoxHeader::read(reader)?;
+        let BoxHeader { name, size: s } = header;
+        let dops = DopsBox::read_box(reader, s)?;
+
+        // This shouldn't happen:
+        let end = start + size;
+        skip_bytes_to(reader, end)?;
+
+        Ok(OpusBox {
+            data_reference_index,
+            channelcount,
+            samplesize,
+            samplerate,
+            dops,
+        })
+    }
+}
+
+impl<W: Write> WriteBox<&mut W> for OpusBox {
+    fn write_box(&self, writer: &mut W) -> Result<u64> {
+        let size = self.box_size();
+        BoxHeader::new(self.box_type(), size).write(writer)?;
+
+        writer.write_u32::<BigEndian>(0)?; // reserved
+        writer.write_u16::<BigEndian>(0)?; // reserved
+        writer.write_u16::<BigEndian>(self.data_reference_index)?;
+
+        writer.write_u64::<BigEndian>(0)?; // reserved
+        writer.write_u16::<BigEndian>(self.channelcount)?;
+        writer.write_u16::<BigEndian>(self.samplesize)?;
+        writer.write_u32::<BigEndian>(0)?; // reserved
+        writer.write_u32::<BigEndian>(self.samplerate.raw_value())?;
+
+        self.dops.write_box(writer)?;
+
+        Ok(size)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
+pub struct ChannelMappingTable {
+    pub stream_count: u8,
+    pub coupled_count: u8,
+    pub channel_mapping: Vec<u8>, // len == channel_count
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
+pub struct DopsBox {
+    pub version: u8,
+    pub channel_count: u8,
+    pub pre_skip: u16,
+    // Input sample rate (32 bits unsigned, little endian): informational only
+    pub sample_rate: u32,
+    // Output gain (16 bits, little endian, signed Q7.8 in dB) to apply when decoding
+    pub output_gain: i16,
+    // Channel mapping family (8 bits unsigned)
+    // -  0 = one stream: mono or L,R stereo
+    // -  1 = channels in vorbis spec order: mono or L,R stereo or ... or FL,C,FR,RL,RR,LFE, ...
+    // -  2..254 = reserved (treat as 255)
+    // -  255 = no defined channel meaning
+    pub channel_mapping_family: u8,
+    // The ChannelMapping field shall be set to the same octet string as
+    // *Channel Mapping* field in the identification header defined in Ogg Opus
+    pub channel_mapping_table: Option<ChannelMappingTable>,
+}
+
+impl DopsBox {
+    pub fn new(config: &OpusConfig) -> Self {
+        Self {
+            version: 0,
+            channel_count: config.chan_conf as u8,
+            pre_skip: config.pre_skip,
+            sample_rate: config.freq_index.freq(),
+            output_gain: 0,
+            channel_mapping_family: 0,
+            channel_mapping_table: None,
+        }
+    }
+}
+
+impl Mp4Box for DopsBox {
+    fn box_type(&self) -> BoxType {
+        BoxType::DopsBox
+    }
+
+    fn box_size(&self) -> u64 {
+        HEADER_SIZE + 11 // TODO add channel mapping table size
+    }
+
+    fn to_json(&self) -> Result<String> {
+        Ok(serde_json::to_string(&self).unwrap())
+    }
+
+    fn summary(&self) -> Result<String> {
+        Ok(String::new())
+    }
+}
+
+impl<R: Read + Seek> ReadBox<&mut R> for DopsBox {
+    fn read_box(reader: &mut R, size: u64) -> Result<Self> {
+        let start = box_start(reader)?;
+        let end = start + size;
+
+        let version = reader.read_u8()?;
+        let channel_count = reader.read_u8()?;
+        let pre_skip = reader.read_u16::<BigEndian>()?;
+        let sample_rate = reader.read_u32::<BigEndian>()?;
+        let output_gain = reader.read_i16::<BigEndian>()?;
+        let channel_mapping_family = reader.read_u8()?;
+
+        // TODO parse channel_mapping_table.
+        skip_bytes_to(reader, end)?;
+
+        Ok(DopsBox {
+            channel_count,
+            version,
+            pre_skip,
+            sample_rate,
+            output_gain,
+            channel_mapping_family,
+            channel_mapping_table: None,
+        })
+    }
+}
+
+impl<W: Write> WriteBox<&mut W> for DopsBox {
+    fn write_box(&self, writer: &mut W) -> Result<u64> {
+        let size = self.box_size();
+        BoxHeader::new(self.box_type(), size).write(writer)?;
+
+        writer.write_u8(self.version)?;
+        writer.write_u8(self.channel_count)?;
+        writer.write_u16::<BigEndian>(self.pre_skip)?;
+        writer.write_u32::<BigEndian>(self.sample_rate)?;
+
+        writer.write_i16::<BigEndian>(self.output_gain)?;
+        writer.write_u8(self.channel_mapping_family)?;
+
+        // TODO write channel_mapping_table
+
+        Ok(size)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::mp4box::BoxHeader;
+    use std::io::Cursor;
+
+    #[test]
+    fn test_opus() {
+        let src_box = OpusBox {
+            data_reference_index: 1,
+            channelcount: 2,
+            samplesize: 16,
+            samplerate: FixedPointU16::new(48000),
+            dops: DopsBox {
+                version: 0,
+                channel_count: 2,
+                pre_skip: 0,
+                sample_rate: 48000,
+                output_gain: 0,
+                channel_mapping_family: 0,
+                channel_mapping_table: None,
+            },
+        };
+        let mut buf = Vec::new();
+        src_box.write_box(&mut buf).unwrap();
+        assert_eq!(buf.len(), src_box.box_size() as usize);
+
+        let mut reader = Cursor::new(&buf);
+        let header = BoxHeader::read(&mut reader).unwrap();
+        assert_eq!(header.name, BoxType::OpusBox);
+        assert_eq!(src_box.box_size(), header.size);
+
+        let dst_box = OpusBox::read_box(&mut reader, header.size).unwrap();
+        assert_eq!(src_box, dst_box);
+    }
+}

src/mp4box/stsd.rs

@@ -4,7 +4,7 @@ use std::io::{Read, Seek, Write};
 
 use crate::mp4box::vp09::Vp09Box;
 use crate::mp4box::*;
-use crate::mp4box::{avc1::Avc1Box, hev1::Hev1Box, mp4a::Mp4aBox, tx3g::Tx3gBox};
+use crate::mp4box::{avc1::Avc1Box, hev1::Hev1Box, mp4a::Mp4aBox, opus::OpusBox, tx3g::Tx3gBox};
 
 #[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
 pub struct StsdBox {
@@ -25,6 +25,9 @@ pub struct StsdBox {
 
     #[serde(skip_serializing_if = "Option::is_none")]
     pub tx3g: Option<Tx3gBox>,
+
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub opus: Option<OpusBox>,
 }
 
 impl StsdBox {
@@ -81,6 +84,7 @@ impl<R: Read + Seek> ReadBox<&mut R> for StsdBox {
         let mut vp09 = None;
         let mut mp4a = None;
         let mut tx3g = None;
+        let mut opus = None;
 
         // Get box header.
         let header = BoxHeader::read(reader)?;
@@ -107,6 +111,9 @@ impl<R: Read + Seek> ReadBox<&mut R> for StsdBox {
             BoxType::Tx3gBox => {
                 tx3g = Some(Tx3gBox::read_box(reader, s)?);
             }
+            BoxType::OpusBox => {
+                opus = Some(OpusBox::read_box(reader, s)?);
+            }
             _ => {}
         }
 
@@ -120,6 +127,7 @@ impl<R: Read + Seek> ReadBox<&mut R> for StsdBox {
             vp09,
             mp4a,
             tx3g,
+            opus,
         })
     }
 }