Crate mpeg2ts_reader [−] [src]

Structures for parsing MPEG2 Transport Stream data, per the ISO/IEC 13818-1 standard.

Design principals

  • Avoid copying and allocating if possible. Most of the implementation works by borrowing slices of the underlying byte buffer. The implementation tries to avoid buffering up intermediate data where practical.
  • Non-blocking. It should be possible to integrate this library into a system non-blocking event-loop. The caller has to 'push' data.
  • Extensible. The standard calls out a number of 'reserved values' and other points of extension. This library should make it possible for other crates to implement such extensions.
  • Minimal. Lots of commonly used Transport Stream functionality is specified in standards from by ISDB / DVB / ATSC / SCTE / etc. and not in 13818-1 itself. I hope support for these features can be added via external crates. (None implemented any yet!)
  • Transport Neutral. There is currently no code here supporting consuming from files or the network. The APIs accept &[u8], and the caller handles providing the data from wherever.

Supported Transport Stream features

Not all Transport Stream features are supported yet. Here's a summary of what's available, and what's yet to come:

  • Framing
    • ☑ ISO/IEC 13818-1 188-byte packets
    • ☐ m2ts 192-byte packets (would be nice if an external crate could support, at least)
  • ☑ Transport Stream packet
    • ☐ Adaptation field
  • ☑ Program Specific Information tables
    • ☑ Section syntax
    • ☑ PAT - Program Association Table
    • ☑ PMT - Program Mapping Table
    • ☐ TSDT - Transport Stream Description Table
  • ☑ Packetised Elementary Stream syntax
    • ☑ PES_packet_data
    • ☑ PTS/DTS
    • ☐ ESCR
    • ☐ ES_rate
    • ☐ DSM_trick_mode
    • ☐ additional_copy_info
    • ☐ PES_CRC
    • ☐ PES_extension

Planned API changes

  • Add 'context' objects
    • Real usage will likely need to thread context objects through the API in order to track application-specific details.
    • Currently mutable state is stored in the instance for each type of syntax parser, and it would be nice to explore extracting this out into parser-specific context types
  • Event generation / remove println!()
    • currently all errors are sent to stdout, which it no way to do things
    • need a way to emit 'events' for interesting data that can't just be a return-value
  • General
    • lots of places return Option but should return Result and a descriptive error

Rust nightly

Currently uses nightly in order to make use of impl Trait. Will probably switch to stable once impl Trait stabilises.

Modules

demultiplex
packet

A Packet struct and associated infrastructure to read an MPEG Transport Stream packet
pes

Support for Packetised Elementary Stream syntax within Transport Stream packet payloads. Elementary streams are split into 'elementary stream packets', which are then further split into the payloads of transport stream packets.
psi

Types for processing tables of Program Specific Information in a transport stream.

Enums

StreamType