hev1 box parser (#101)

Co-authored-by: Alfred Gutierrez <alfg@users.noreply.github.com>

src/mp4box/avc1.rs

@@ -101,30 +101,37 @@ impl<R: Read + Seek> ReadBox<&mut R> for Avc1Box {
         let depth = reader.read_u16::<BigEndian>()?;
         reader.read_i16::<BigEndian>()?; // pre-defined
 
-        let header = BoxHeader::read(reader)?;
-        let BoxHeader { name, size: s } = header;
-        if s > size {
-            return Err(Error::InvalidData(
-                "avc1 box contains a box with a larger size than it",
-            ));
-        }
-        if name == BoxType::AvcCBox {
-            let avcc = AvcCBox::read_box(reader, s)?;
+        let end = start + size;
+        loop {
+            let current = reader.stream_position()?;
+            if current >= end {
+                return Err(Error::InvalidData("avcc not found"));
+            }
+            let header = BoxHeader::read(reader)?;
+            let BoxHeader { name, size: s } = header;
+            if s > size {
+                return Err(Error::InvalidData(
+                    "avc1 box contains a box with a larger size than it",
+                ));
+            }
+            if name == BoxType::AvcCBox {
+                let avcc = AvcCBox::read_box(reader, s)?;
 
-            skip_bytes_to(reader, start + size)?;
+                skip_bytes_to(reader, start + size)?;
 
-            Ok(Avc1Box {
-                data_reference_index,
-                width,
-                height,
-                horizresolution,
-                vertresolution,
-                frame_count,
-                depth,
-                avcc,
-            })
-        } else {
-            Err(Error::InvalidData("avcc not found"))
+                return Ok(Avc1Box {
+                    data_reference_index,
+                    width,
+                    height,
+                    horizresolution,
+                    vertresolution,
+                    frame_count,
+                    depth,
+                    avcc,
+                });
+            } else {
+                skip_bytes_to(reader, current + s)?;
+            }
         }
     }
 }

src/mp4box/dinf.rs

@@ -264,22 +264,16 @@ impl<R: Read + Seek> ReadBox<&mut R> for UrlBox {
 
         let (version, flags) = read_box_header_ext(reader)?;
 
-        let location = if size.saturating_sub(HEADER_SIZE + HEADER_EXT_SIZE) > 0 {
-            let buf_size = size - HEADER_SIZE - HEADER_EXT_SIZE - 1;
-            let mut buf = vec![0u8; buf_size as usize];
-            reader.read_exact(&mut buf)?;
-            match String::from_utf8(buf) {
-                Ok(t) => {
-                    if t.len() != buf_size as usize {
-                        return Err(Error::InvalidData("string too small"));
-                    }
-                    t
-                }
-                _ => String::default(),
-            }
-        } else {
-            String::default()
-        };
+        let buf_size = size
+            .checked_sub(HEADER_SIZE + HEADER_EXT_SIZE)
+            .ok_or(Error::InvalidData("url size too small"))?;
+
+        let mut buf = vec![0u8; buf_size as usize];
+        reader.read_exact(&mut buf)?;
+        if let Some(end) = buf.iter().position(|&b| b == b'\0') {
+            buf.truncate(end);
+        }
+        let location = String::from_utf8(buf).unwrap_or_default();
 
         skip_bytes_to(reader, start + size)?;
 

src/mp4box/hdlr.rs

@@ -53,20 +53,15 @@ impl<R: Read + Seek> ReadBox<&mut R> for HdlrBox {
         skip_bytes(reader, 12)?; // reserved
 
         let buf_size = size
-            .checked_sub(HEADER_SIZE + HEADER_EXT_SIZE + 20 + 1)
+            .checked_sub(HEADER_SIZE + HEADER_EXT_SIZE + 20)
             .ok_or(Error::InvalidData("hdlr size too small"))?;
+
         let mut buf = vec![0u8; buf_size as usize];
         reader.read_exact(&mut buf)?;
-
-        let handler_string = match String::from_utf8(buf) {
-            Ok(t) => {
-                if t.len() != buf_size as usize {
-                    return Err(Error::InvalidData("string too small"));
-                }
-                t
-            }
-            _ => String::from("null"),
-        };
+        if let Some(end) = buf.iter().position(|&b| b == b'\0') {
+            buf.truncate(end);
+        }
+        let handler_string = String::from_utf8(buf).unwrap_or_default();
 
         skip_bytes_to(reader, start + size)?;
 
@@ -127,4 +122,52 @@ mod tests {
         let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
         assert_eq!(src_box, dst_box);
     }
+
+    #[test]
+    fn test_hdlr_empty() {
+        let src_box = HdlrBox {
+            version: 0,
+            flags: 0,
+            handler_type: str::parse::<FourCC>("vide").unwrap(),
+            name: String::new(),
+        };
+        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::HdlrBox);
+        assert_eq!(src_box.box_size(), header.size);
+
+        let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
+        assert_eq!(src_box, dst_box);
+    }
+
+    #[test]
+    fn test_hdlr_extra() {
+        let real_src_box = HdlrBox {
+            version: 0,
+            flags: 0,
+            handler_type: str::parse::<FourCC>("vide").unwrap(),
+            name: String::from("Good"),
+        };
+        let src_box = HdlrBox {
+            version: 0,
+            flags: 0,
+            handler_type: str::parse::<FourCC>("vide").unwrap(),
+            name: String::from_utf8(b"Good\0Bad".to_vec()).unwrap(),
+        };
+        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::HdlrBox);
+        assert_eq!(src_box.box_size(), header.size);
+
+        let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
+        assert_eq!(real_src_box, dst_box);
+    }
 }

src/mp4box/hev1.rs

@@ -158,15 +158,33 @@ impl<W: Write> WriteBox<&mut W> for Hev1Box {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
+#[derive(Default, Debug, Clone, PartialEq, Eq, Serialize)]
 pub struct HvcCBox {
     pub configuration_version: u8,
+    pub general_profile_space: u8,
+    pub general_tier_flag: bool,
+    pub general_profile_idc: u8,
+    pub general_profile_compatibility_flags: u32,
+    pub general_constraint_indicator_flag: u64,
+    pub general_level_idc: u8,
+    pub min_spatial_segmentation_idc: u16,
+    pub parallelism_type: u8,
+    pub chroma_format_idc: u8,
+    pub bit_depth_luma_minus8: u8,
+    pub bit_depth_chroma_minus8: u8,
+    pub avg_frame_rate: u16,
+    pub constant_frame_rate: u8,
+    pub num_temporal_layers: u8,
+    pub temporal_id_nested: bool,
+    pub length_size_minus_one: u8,
+    pub arrays: Vec<HvcCArray>,
 }
 
 impl HvcCBox {
     pub fn new() -> Self {
         Self {
             configuration_version: 1,
+            ..Default::default()
         }
     }
 }
@@ -177,7 +195,13 @@ impl Mp4Box for HvcCBox {
     }
 
     fn box_size(&self) -> u64 {
-        HEADER_SIZE + 1
+        HEADER_SIZE
+            + 23
+            + self
+                .arrays
+                .iter()
+                .map(|a| 3 + a.nalus.iter().map(|x| 2 + x.data.len() as u64).sum::<u64>())
+                .sum::<u64>()
     }
 
     fn to_json(&self) -> Result<String> {
@@ -185,21 +209,108 @@ impl Mp4Box for HvcCBox {
     }
 
     fn summary(&self) -> Result<String> {
-        let s = format!("configuration_version={}", self.configuration_version);
-        Ok(s)
+        Ok(format!("configuration_version={} general_profile_space={} general_tier_flag={} general_profile_idc={} general_profile_compatibility_flags={} general_constraint_indicator_flag={} general_level_idc={} min_spatial_segmentation_idc={} parallelism_type={} chroma_format_idc={} bit_depth_luma_minus8={} bit_depth_chroma_minus8={} avg_frame_rate={} constant_frame_rate={} num_temporal_layers={} temporal_id_nested={} length_size_minus_one={}", 
+            self.configuration_version,
+            self.general_profile_space,
+            self.general_tier_flag,
+            self.general_profile_idc,
+            self.general_profile_compatibility_flags,
+            self.general_constraint_indicator_flag,
+            self.general_level_idc,
+            self.min_spatial_segmentation_idc,
+            self.parallelism_type,
+            self.chroma_format_idc,
+            self.bit_depth_luma_minus8,
+            self.bit_depth_chroma_minus8,
+            self.avg_frame_rate,
+            self.constant_frame_rate,
+            self.num_temporal_layers,
+            self.temporal_id_nested,
+            self.length_size_minus_one
+        ))
     }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
+pub struct HvcCArrayNalu {
+    pub size: u16,
+    pub data: Vec<u8>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
+pub struct HvcCArray {
+    pub completeness: bool,
+    pub nal_unit_type: u8,
+    pub nalus: Vec<HvcCArrayNalu>,
+}
+
 impl<R: Read + Seek> ReadBox<&mut R> for HvcCBox {
-    fn read_box(reader: &mut R, size: u64) -> Result<Self> {
-        let start = box_start(reader)?;
-
+    fn read_box(reader: &mut R, _size: u64) -> Result<Self> {
         let configuration_version = reader.read_u8()?;
+        let params = reader.read_u8()?;
+        let general_profile_space = params & 0b11000000 >> 6;
+        let general_tier_flag = (params & 0b00100000 >> 5) > 0;
+        let general_profile_idc = params & 0b00011111;
 
-        skip_bytes_to(reader, start + size)?;
+        let general_profile_compatibility_flags = reader.read_u32::<BigEndian>()?;
+        let general_constraint_indicator_flag = reader.read_u48::<BigEndian>()?;
+        let general_level_idc = reader.read_u8()?;
+        let min_spatial_segmentation_idc = reader.read_u16::<BigEndian>()? & 0x0FFF;
+        let parallelism_type = reader.read_u8()? & 0b11;
+        let chroma_format_idc = reader.read_u8()? & 0b11;
+        let bit_depth_luma_minus8 = reader.read_u8()? & 0b111;
+        let bit_depth_chroma_minus8 = reader.read_u8()? & 0b111;
+        let avg_frame_rate = reader.read_u16::<BigEndian>()?;
+
+        let params = reader.read_u8()?;
+        let constant_frame_rate = params & 0b11000000 >> 6;
+        let num_temporal_layers = params & 0b00111000 >> 3;
+        let temporal_id_nested = (params & 0b00000100 >> 2) > 0;
+        let length_size_minus_one = params & 0b000011;
+
+        let num_of_arrays = reader.read_u8()?;
+
+        let mut arrays = Vec::with_capacity(num_of_arrays as _);
+        for _ in 0..num_of_arrays {
+            let params = reader.read_u8()?;
+            let num_nalus = reader.read_u16::<BigEndian>()?;
+            let mut nalus = Vec::with_capacity(num_nalus as usize);
+
+            for _ in 0..num_nalus {
+                let size = reader.read_u16::<BigEndian>()?;
+                let mut data = vec![0; size as usize];
+
+                reader.read_exact(&mut data)?;
+
+                nalus.push(HvcCArrayNalu { size, data })
+            }
+
+            arrays.push(HvcCArray {
+                completeness: (params & 0b10000000) > 0,
+                nal_unit_type: params & 0b111111,
+                nalus,
+            });
+        }
 
         Ok(HvcCBox {
             configuration_version,
+            general_profile_space,
+            general_tier_flag,
+            general_profile_idc,
+            general_profile_compatibility_flags,
+            general_constraint_indicator_flag,
+            general_level_idc,
+            min_spatial_segmentation_idc,
+            parallelism_type,
+            chroma_format_idc,
+            bit_depth_luma_minus8,
+            bit_depth_chroma_minus8,
+            avg_frame_rate,
+            constant_frame_rate,
+            num_temporal_layers,
+            temporal_id_nested,
+            length_size_minus_one,
+            arrays,
         })
     }
 }
@@ -210,6 +321,40 @@ impl<W: Write> WriteBox<&mut W> for HvcCBox {
         BoxHeader::new(self.box_type(), size).write(writer)?;
 
         writer.write_u8(self.configuration_version)?;
+        let general_profile_space = (self.general_profile_space & 0b11) << 6;
+        let general_tier_flag = u8::from(self.general_tier_flag) << 5;
+        let general_profile_idc = self.general_profile_idc & 0b11111;
+
+        writer.write_u8(general_profile_space | general_tier_flag | general_profile_idc)?;
+        writer.write_u32::<BigEndian>(self.general_profile_compatibility_flags)?;
+        writer.write_u48::<BigEndian>(self.general_constraint_indicator_flag)?;
+        writer.write_u8(self.general_level_idc)?;
+
+        writer.write_u16::<BigEndian>(self.min_spatial_segmentation_idc & 0x0FFF)?;
+        writer.write_u8(self.parallelism_type & 0b11)?;
+        writer.write_u8(self.chroma_format_idc & 0b11)?;
+        writer.write_u8(self.bit_depth_luma_minus8 & 0b111)?;
+        writer.write_u8(self.bit_depth_chroma_minus8 & 0b111)?;
+        writer.write_u16::<BigEndian>(self.avg_frame_rate)?;
+
+        let constant_frame_rate = (self.constant_frame_rate & 0b11) << 6;
+        let num_temporal_layers = (self.num_temporal_layers & 0b111) << 3;
+        let temporal_id_nested = u8::from(self.temporal_id_nested) << 2;
+        let length_size_minus_one = self.length_size_minus_one & 0b11;
+        writer.write_u8(
+            constant_frame_rate | num_temporal_layers | temporal_id_nested | length_size_minus_one,
+        )?;
+        writer.write_u8(self.arrays.len() as u8)?;
+        for arr in &self.arrays {
+            writer.write_u8((arr.nal_unit_type & 0b111111) | u8::from(arr.completeness) << 7)?;
+            writer.write_u16::<BigEndian>(arr.nalus.len() as _)?;
+
+            for nalu in &arr.nalus {
+                writer.write_u16::<BigEndian>(nalu.size)?;
+                writer.write_all(&nalu.data)?;
+            }
+        }
+
         Ok(size)
     }
 }
@@ -232,6 +377,7 @@ mod tests {
             depth: 24,
             hvcc: HvcCBox {
                 configuration_version: 1,
+                ..Default::default()
             },
         };
         let mut buf = Vec::new();

src/mp4box/mod.rs

@@ -106,10 +106,49 @@ pub(crate) mod vmhd;
 pub(crate) mod vp09;
 pub(crate) mod vpcc;
 
+pub use avc1::Avc1Box;
+pub use co64::Co64Box;
+pub use ctts::CttsBox;
+pub use data::DataBox;
+pub use dinf::DinfBox;
+pub use edts::EdtsBox;
+pub use elst::ElstBox;
 pub use emsg::EmsgBox;
 pub use ftyp::FtypBox;
+pub use hdlr::HdlrBox;
+pub use hev1::Hev1Box;
+pub use ilst::IlstBox;
+pub use mdhd::MdhdBox;
+pub use mdia::MdiaBox;
+pub use mehd::MehdBox;
+pub use meta::MetaBox;
+pub use mfhd::MfhdBox;
+pub use minf::MinfBox;
 pub use moof::MoofBox;
 pub use moov::MoovBox;
+pub use mp4a::Mp4aBox;
+pub use mvex::MvexBox;
+pub use mvhd::MvhdBox;
+pub use smhd::SmhdBox;
+pub use stbl::StblBox;
+pub use stco::StcoBox;
+pub use stsc::StscBox;
+pub use stsd::StsdBox;
+pub use stss::StssBox;
+pub use stsz::StszBox;
+pub use stts::SttsBox;
+pub use tfdt::TfdtBox;
+pub use tfhd::TfhdBox;
+pub use tkhd::TkhdBox;
+pub use traf::TrafBox;
+pub use trak::TrakBox;
+pub use trex::TrexBox;
+pub use trun::TrunBox;
+pub use tx3g::Tx3gBox;
+pub use udta::UdtaBox;
+pub use vmhd::VmhdBox;
+pub use vp09::Vp09Box;
+pub use vpcc::VpccBox;
 
 pub const HEADER_SIZE: u64 = 8;
 // const HEADER_LARGE_SIZE: u64 = 16;
@@ -198,7 +237,8 @@ boxtype! {
     DayBox => 0xa9646179,
     CovrBox => 0x636f7672,
     DescBox => 0x64657363,
-    WideBox => 0x77696465
+    WideBox => 0x77696465,
+    WaveBox => 0x77617665
 }
 
 pub trait Mp4Box: Sized {

src/mp4box/mp4a.rs

@@ -82,16 +82,28 @@ impl<R: Read + Seek> ReadBox<&mut R> for Mp4aBox {
         reader.read_u32::<BigEndian>()?; // reserved
         reader.read_u16::<BigEndian>()?; // reserved
         let data_reference_index = reader.read_u16::<BigEndian>()?;
-
-        reader.read_u64::<BigEndian>()?; // reserved
+        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>()?);
 
+        if version == 1 {
+            // Skip QTFF
+            reader.read_u64::<BigEndian>()?;
+            reader.read_u64::<BigEndian>()?;
+        }
+
+        // Find esds in mp4a or wave
         let mut esds = None;
-        let current = reader.stream_position()?;
-        if current < start + size {
+        let end = start + size;
+        loop {
+            let current = reader.stream_position()?;
+            if current >= end {
+                break;
+            }
             let header = BoxHeader::read(reader)?;
             let BoxHeader { name, size: s } = header;
             if s > size {
@@ -99,13 +111,20 @@ impl<R: Read + Seek> ReadBox<&mut R> for Mp4aBox {
                     "mp4a box contains a box with a larger size than it",
                 ));
             }
-
             if name == BoxType::EsdsBox {
                 esds = Some(EsdsBox::read_box(reader, s)?);
+                break;
+            } else if name == BoxType::WaveBox {
+                // Typically contains frma, mp4a, esds, and a terminator atom
+            } else {
+                // Skip boxes
+                let skip_to = current + s;
+                skip_bytes_to(reader, skip_to)?;
             }
-            skip_bytes_to(reader, start + size)?;
         }
 
+        skip_bytes_to(reader, end)?;
+
         Ok(Mp4aBox {
             data_reference_index,
             channelcount,
@@ -585,9 +604,9 @@ impl<R: Read + Seek> ReadDesc<&mut R> for SLConfigDescriptor {
 impl<W: Write> WriteDesc<&mut W> for SLConfigDescriptor {
     fn write_desc(&self, writer: &mut W) -> Result<u32> {
         let size = Self::desc_size();
-        write_desc(writer, Self::desc_tag(), size - 1)?;
+        write_desc(writer, Self::desc_tag(), size)?;
 
-        writer.write_u8(0)?; // pre-defined
+        writer.write_u8(2)?; // pre-defined
         Ok(size)
     }
 }

src/mp4box/tfhd.rs

@@ -22,6 +22,8 @@ impl TfhdBox {
     pub const FLAG_DEFAULT_SAMPLE_DURATION: u32 = 0x08;
     pub const FLAG_DEFAULT_SAMPLE_SIZE: u32 = 0x10;
     pub const FLAG_DEFAULT_SAMPLE_FLAGS: u32 = 0x20;
+    pub const FLAG_DURATION_IS_EMPTY: u32 = 0x10000;
+    pub const FLAG_DEFAULT_BASE_IS_MOOF: u32 = 0x20000;
 
     pub fn get_type(&self) -> BoxType {
         BoxType::TfhdBox

src/mp4box/traf.rs

@@ -19,6 +19,9 @@ impl TrafBox {
     pub fn get_size(&self) -> u64 {
         let mut size = HEADER_SIZE;
         size += self.tfhd.box_size();
+        if let Some(ref tfdt) = self.tfdt {
+            size += tfdt.box_size();
+        }
         if let Some(ref trun) = self.trun {
             size += trun.box_size();
         }
@@ -104,6 +107,12 @@ impl<W: Write> WriteBox<&mut W> for TrafBox {
         BoxHeader::new(self.box_type(), size).write(writer)?;
 
         self.tfhd.write_box(writer)?;
+        if let Some(ref tfdt) = self.tfdt {
+            tfdt.write_box(writer)?;
+        }
+        if let Some(ref trun) = self.trun {
+            trun.write_box(writer)?;
+        }
 
         Ok(size)
     }

src/reader.rs

@@ -24,6 +24,7 @@ impl<R: Read + Seek> Mp4Reader<R> {
         let mut ftyp = None;
         let mut moov = None;
         let mut moofs = Vec::new();
+        let mut moof_offsets = Vec::new();
         let mut emsgs = Vec::new();
 
         let mut current = start;
@@ -57,8 +58,10 @@ impl<R: Read + Seek> Mp4Reader<R> {
                     moov = Some(MoovBox::read_box(&mut reader, s)?);
                 }
                 BoxType::MoofBox => {
+                    let moof_offset = reader.stream_position()? - 8;
                     let moof = MoofBox::read_box(&mut reader, s)?;
                     moofs.push(moof);
+                    moof_offsets.push(moof_offset);
                 }
                 BoxType::EmsgBox => {
                     let emsg = EmsgBox::read_box(&mut reader, s)?;
@@ -101,11 +104,12 @@ impl<R: Read + Seek> Mp4Reader<R> {
                 }
             }
 
-            for moof in moofs.iter() {
+            for (moof, moof_offset) in moofs.iter().zip(moof_offsets) {
                 for traf in moof.trafs.iter() {
                     let track_id = traf.tfhd.track_id;
                     if let Some(track) = tracks.get_mut(&track_id) {
                         track.default_sample_duration = default_sample_duration;
+                        track.moof_offsets.push(moof_offset);
                         track.trafs.push(traf.clone())
                     } else {
                         return Err(Error::TrakNotFound(track_id));
@@ -125,6 +129,92 @@ impl<R: Read + Seek> Mp4Reader<R> {
         })
     }
 
+    pub fn read_fragment_header<FR: Read + Seek>(
+        &self,
+        mut reader: FR,
+        size: u64,
+    ) -> Result<Mp4Reader<FR>> {
+        let start = reader.stream_position()?;
+
+        let mut moofs = Vec::new();
+        let mut moof_offsets = Vec::new();
+
+        let mut current = start;
+        while current < size {
+            // Get box header.
+            let header = BoxHeader::read(&mut reader)?;
+            let BoxHeader { name, size: s } = header;
+            if s > size {
+                return Err(Error::InvalidData(
+                    "file contains a box with a larger size than it",
+                ));
+            }
+
+            // Break if size zero BoxHeader, which can result in dead-loop.
+            if s == 0 {
+                break;
+            }
+
+            // Match and parse the atom boxes.
+            match name {
+                BoxType::MdatBox => {
+                    skip_box(&mut reader, s)?;
+                }
+                BoxType::MoofBox => {
+                    let moof_offset = reader.stream_position()? - 8;
+                    let moof = MoofBox::read_box(&mut reader, s)?;
+                    moofs.push(moof);
+                    moof_offsets.push(moof_offset);
+                }
+                _ => {
+                    // XXX warn!()
+                    skip_box(&mut reader, s)?;
+                }
+            }
+            current = reader.stream_position()?;
+        }
+
+        if moofs.is_empty() {
+            return Err(Error::BoxNotFound(BoxType::MoofBox));
+        }
+
+        let size = current - start;
+        let mut tracks: HashMap<u32, Mp4Track> = self
+            .moov
+            .traks
+            .iter()
+            .map(|trak| (trak.tkhd.track_id, Mp4Track::from(trak)))
+            .collect();
+
+        let mut default_sample_duration = 0;
+        if let Some(ref mvex) = &self.moov.mvex {
+            default_sample_duration = mvex.trex.default_sample_duration
+        }
+
+        for (moof, moof_offset) in moofs.iter().zip(moof_offsets) {
+            for traf in moof.trafs.iter() {
+                let track_id = traf.tfhd.track_id;
+                if let Some(track) = tracks.get_mut(&track_id) {
+                    track.default_sample_duration = default_sample_duration;
+                    track.moof_offsets.push(moof_offset);
+                    track.trafs.push(traf.clone())
+                } else {
+                    return Err(Error::TrakNotFound(track_id));
+                }
+            }
+        }
+
+        Ok(Mp4Reader {
+            reader,
+            ftyp: self.ftyp.clone(),
+            moov: self.moov.clone(),
+            moofs,
+            emsgs: Vec::new(),
+            tracks,
+            size,
+        })
+    }
+
     pub fn size(&self) -> u64 {
         self.size
     }
@@ -172,6 +262,14 @@ impl<R: Read + Seek> Mp4Reader<R> {
             Err(Error::TrakNotFound(track_id))
         }
     }
+
+    pub fn sample_offset(&mut self, track_id: u32, sample_id: u32) -> Result<u64> {
+        if let Some(track) = self.tracks.get(&track_id) {
+            track.sample_offset(sample_id)
+        } else {
+            Err(Error::TrakNotFound(track_id))
+        }
+    }
 }
 
 impl<R> Mp4Reader<R> {

src/track.rs

@@ -6,6 +6,7 @@ use std::time::Duration;
 
 use crate::mp4box::traf::TrafBox;
 use crate::mp4box::trak::TrakBox;
+use crate::mp4box::trun::TrunBox;
 use crate::mp4box::{
     avc1::Avc1Box, co64::Co64Box, ctts::CttsBox, ctts::CttsEntry, hev1::Hev1Box, mp4a::Mp4aBox,
     smhd::SmhdBox, stco::StcoBox, stsc::StscEntry, stss::StssBox, stts::SttsEntry, tx3g::Tx3gBox,
@@ -92,6 +93,7 @@ impl From<Vp9Config> for TrackConfig {
 pub struct Mp4Track {
     pub trak: TrakBox,
     pub trafs: Vec<TrafBox>,
+    pub moof_offsets: Vec<u64>,
 
     // Fragmented Tracks Defaults.
     pub default_sample_duration: u32,
@@ -103,6 +105,7 @@ impl Mp4Track {
         Self {
             trak,
             trafs: Vec::new(),
+            moof_offsets: Vec::new(),
             default_sample_duration: 0,
         }
     }
@@ -164,11 +167,11 @@ impl Mp4Track {
     }
 
     pub fn frame_rate(&self) -> f64 {
-        let dur_msec = self.duration().as_millis() as u64;
-        if dur_msec > 0 {
-            ((self.sample_count() as u64 * 1000) / dur_msec) as f64
-        } else {
+        let dur = self.duration();
+        if dur.is_zero() {
             0.0
+        } else {
+            self.sample_count() as f64 / dur.as_secs_f64()
         }
     }
 
@@ -219,12 +222,12 @@ impl Mp4Track {
             }
             // mp4a.esds.es_desc.dec_config.avg_bitrate
         } else {
-            let dur_sec = self.duration().as_secs();
-            if dur_sec > 0 {
-                let bitrate = self.total_sample_size() * 8 / dur_sec;
-                bitrate as u32
-            } else {
+            let dur = self.duration();
+            if dur.is_zero() {
                 0
+            } else {
+                let bitrate = self.total_sample_size() as f64 * 8.0 / dur.as_secs_f64();
+                bitrate as u32
             }
         }
     }
@@ -434,10 +437,34 @@ impl Mp4Track {
         }
     }
 
-    fn sample_offset(&self, sample_id: u32) -> Result<u64> {
+    pub fn sample_offset(&self, sample_id: u32) -> Result<u64> {
         if !self.trafs.is_empty() {
-            if let Some((traf_idx, _sample_idx)) = self.find_traf_idx_and_sample_idx(sample_id) {
-                Ok(self.trafs[traf_idx].tfhd.base_data_offset.unwrap_or(0))
+            if let Some((traf_idx, sample_idx)) = self.find_traf_idx_and_sample_idx(sample_id) {
+                let mut sample_offset = self.trafs[traf_idx]
+                    .tfhd
+                    .base_data_offset
+                    .unwrap_or(self.moof_offsets[traf_idx]);
+
+                if let Some(data_offset) = self.trafs[traf_idx]
+                    .trun
+                    .as_ref()
+                    .and_then(|trun| trun.data_offset)
+                {
+                    sample_offset = sample_offset.checked_add_signed(data_offset as i64).ok_or(
+                        Error::InvalidData("attempt to calculate trun sample offset with overflow"),
+                    )?;
+                }
+
+                let first_sample_in_trun = sample_id - sample_idx as u32;
+                for i in first_sample_in_trun..sample_id {
+                    sample_offset = sample_offset
+                        .checked_add(self.sample_size(i)? as u64)
+                        .ok_or(Error::InvalidData(
+                            "attempt to calculate trun entry sample offset with overflow",
+                        ))?;
+                }
+
+                Ok(sample_offset)
             } else {
                 Err(Error::BoxInTrafNotFound(self.track_id(), BoxType::TrafBox))
             }
@@ -473,15 +500,38 @@ impl Mp4Track {
     }
 
     fn sample_time(&self, sample_id: u32) -> Result<(u64, u32)> {
-        let stts = &self.trak.mdia.minf.stbl.stts;
-
-        let mut sample_count: u32 = 1;
-        let mut elapsed = 0;
-
         if !self.trafs.is_empty() {
-            let start_time = ((sample_id - 1) * self.default_sample_duration) as u64;
-            Ok((start_time, self.default_sample_duration))
+            let mut base_start_time = 0;
+            let mut default_sample_duration = self.default_sample_duration;
+            if let Some((traf_idx, sample_idx)) = self.find_traf_idx_and_sample_idx(sample_id) {
+                let traf = &self.trafs[traf_idx];
+                if let Some(tfdt) = &traf.tfdt {
+                    base_start_time = tfdt.base_media_decode_time;
+                }
+                if let Some(duration) = traf.tfhd.default_sample_duration {
+                    default_sample_duration = duration;
+                }
+                if let Some(trun) = &traf.trun {
+                    if TrunBox::FLAG_SAMPLE_DURATION & trun.flags != 0 {
+                        let mut start_offset = 0u64;
+                        for duration in &trun.sample_durations[..sample_idx] {
+                            start_offset = start_offset.checked_add(*duration as u64).ok_or(
+                                Error::InvalidData("attempt to sum sample durations with overflow"),
+                            )?;
+                        }
+                        let duration = trun.sample_durations[sample_idx];
+                        return Ok((base_start_time + start_offset, duration));
+                    }
+                }
+            }
+            let start_offset = ((sample_id - 1) * default_sample_duration) as u64;
+            Ok((base_start_time + start_offset, default_sample_duration))
         } else {
+            let stts = &self.trak.mdia.minf.stbl.stts;
+
+            let mut sample_count: u32 = 1;
+            let mut elapsed = 0;
+
             for entry in stts.entries.iter() {
                 let new_sample_count =
                     sample_count
@@ -508,7 +558,17 @@ impl Mp4Track {
     }
 
     fn sample_rendering_offset(&self, sample_id: u32) -> i32 {
-        if let Some(ref ctts) = self.trak.mdia.minf.stbl.ctts {
+        if !self.trafs.is_empty() {
+            if let Some((traf_idx, sample_idx)) = self.find_traf_idx_and_sample_idx(sample_id) {
+                if let Some(cts) = self.trafs[traf_idx]
+                    .trun
+                    .as_ref()
+                    .and_then(|trun| trun.sample_cts.get(sample_idx))
+                {
+                    return *cts as i32;
+                }
+            }
+        } else if let Some(ref ctts) = self.trak.mdia.minf.stbl.ctts {
             if let Ok((ctts_index, _)) = self.ctts_index(sample_id) {
                 let ctts_entry = ctts.entries.get(ctts_index).unwrap();
                 return ctts_entry.sample_offset;

src/types.rs

@@ -657,15 +657,21 @@ pub fn creation_time(creation_time: u64) -> u64 {
     }
 }
 
-#[derive(Debug, Default, Clone, PartialEq, Eq, Serialize)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
 pub enum DataType {
-    #[default]
     Binary = 0x000000,
     Text = 0x000001,
     Image = 0x00000D,
     TempoCpil = 0x000015,
 }
 
+#[allow(clippy::derivable_impls)]
+impl std::default::Default for DataType {
+    fn default() -> Self {
+        DataType::Binary
+    }
+}
+
 impl TryFrom<u32> for DataType {
     type Error = Error;
     fn try_from(value: u32) -> Result<DataType> {

tests/lib.rs

@@ -99,8 +99,8 @@ fn test_read_mp4() {
     assert_eq!(track1.video_profile().unwrap(), AvcProfile::AvcHigh);
     assert_eq!(track1.width(), 320);
     assert_eq!(track1.height(), 240);
-    assert_eq!(track1.bitrate(), 0); // XXX
-    assert_eq!(track1.frame_rate(), 25.00); // XXX
+    assert_eq!(track1.bitrate(), 150200);
+    assert_eq!(track1.frame_rate(), 25.00);
 
     // track #2
     let track2 = mp4.tracks().get(&2).unwrap();
@@ -176,3 +176,36 @@ fn test_read_metadata() {
     assert_eq!(poster.len(), want_poster.len());
     assert_eq!(poster, want_poster.as_slice());
 }
+
+#[test]
+fn test_read_fragments() {
+    let mp4 = get_reader("tests/samples/minimal_init.mp4");
+
+    assert_eq!(692, mp4.size());
+    assert_eq!(5, mp4.compatible_brands().len());
+
+    let sample_count = mp4.sample_count(1).unwrap();
+    assert_eq!(sample_count, 0);
+
+    let f = File::open("tests/samples/minimal_fragment.m4s").unwrap();
+    let f_size = f.metadata().unwrap().len();
+    let frag_reader = BufReader::new(f);
+
+    let mut mp4_fragment = mp4.read_fragment_header(frag_reader, f_size).unwrap();
+    let sample_count = mp4_fragment.sample_count(1).unwrap();
+    assert_eq!(sample_count, 1);
+    let sample_1_1 = mp4_fragment.read_sample(1, 1).unwrap().unwrap();
+    assert_eq!(sample_1_1.bytes.len(), 751);
+    assert_eq!(
+        sample_1_1,
+        mp4::Mp4Sample {
+            start_time: 0,
+            duration: 512,
+            rendering_offset: 0,
+            is_sync: true,
+            bytes: mp4::Bytes::from(vec![0x0u8; 751]),
+        }
+    );
+    let eos = mp4_fragment.read_sample(1, 2);
+    assert!(eos.is_err());
+}