oximedia-io

I/O layer for the OxiMedia multimedia framework.

Part of the OxiMedia multimedia framework.

Features

• Magic-byte format detection — identifies over 45 media formats (MP4, MKV, AVI, WebM, MXF, FLAC, WAV, PNG, JPEG, WebP, DPX, EXR, JPEG-XL, and more) from a leading-bytes buffer
• Media sources — unified async MediaSource trait with FileSource (tokio) and MemorySource (bytes::Bytes) implementations
• Bit-level reading — MSB-first BitReader for video bitstream parsing; unsigned and signed Exp-Golomb (ue(v) / se(v)) coding for H.264-style syntax
• MXF probing — lightweight parser for MXF Header Partition Pack, operational pattern, and essence tracks
• Content detection — text encoding (UTF-8, UTF-16, Latin-1) and binary-vs-text heuristics
• Aligned I/O — memory-aligned reads and writes for DMA-friendly transfers
• Buffered I/O — read-ahead buffering; synchronous buffered reader
• Memory-mapped I/O — zero-copy mmap-based file access
• Scatter-gather I/O — vectorized multi-buffer I/O
• Checksums — CRC32, CRC64, SHA-256, BLAKE3
• Compression — zstd, LZ4, gzip, bzip2 (compress/decompress)
• Progress reader — async reader with callback for upload/download progress
• Rate limiter — bandwidth-limited I/O
• Ring buffer — lock-free ring buffer for streaming pipelines
• Retrying source — automatic retry on transient I/O errors
• Chunked writer — write large outputs in fixed-size chunks
• Copy engine — high-throughput async file copy
• Temp files — secure temporary file creation and cleanup
• Verification I/O — read-back verification for write integrity
• Write journal — journaled writes for crash-safe I/O
• File metadata — extended file attributes (size, timestamps, permissions)
• File watching — file system event watching

Usage

[dependencies]
oximedia-io = "0.1.5"

Detect media format

use oximedia_io::format_detector::FormatDetector;

let header = std::fs::read("input.mkv").unwrap();
let detection = FormatDetector::detect(&header);
println!("format: {:?}", detection.format);  // MediaFormat::Mkv
println!("mime:   {}", detection.mime_type); // "video/x-matroska"

Async file source

use oximedia_io::source::{FileSource, MediaSource};

#[tokio::main]
async fn main() -> oximedia_core::OxiResult<()> {
    let mut source = FileSource::open("video.webm").await?;
    let mut buf = [0u8; 4096];
    let n = source.read(&mut buf).await?;
    println!("read {n} bytes");
    Ok(())
}

Bit-level parsing (H.264 SPS)

use oximedia_io::bits::BitReader;

let sps = [0x64u8, 0x00, 0x1f];  // profile_idc=100, flags=0, level_idc=31
let mut r = BitReader::new(&sps);
let profile_idc = r.read_bits(8).unwrap(); // 100 — High Profile
let _flags      = r.read_bits(6).unwrap();
let level_idc   = r.read_bits(8).unwrap(); // 31 — Level 3.1
assert_eq!(profile_idc, 100);
assert_eq!(level_idc,    31);

Exp-Golomb coding

use oximedia_io::bits::BitReader;

// ue(0) is encoded as a single `1` bit
let data = [0b10000000u8];
let mut r = BitReader::new(&data);
assert_eq!(r.read_exp_golomb().unwrap(), 0);

API Overview

Status

Alpha — API may change between minor versions.

License

Apache-2.0 — Copyright 2024-2026 COOLJAPAN OU (Team Kitasan)