# openipc-core
Shared protocol code for `openipc-rs`.
This crate contains the parts of the OpenIPC receive path that do not need to
know whether bytes came from native USB, WebUSB, a capture file, or a test
fixture. It is the right dependency when you want to parse or reconstruct
OpenIPC video without taking a dependency on a specific USB frontend.
## What It Does
- Parse Realtek rtl88xx USB RX aggregates and 24-byte RX descriptors.
- Filter OpenIPC/WFB 802.11 frames by channel id and radio port.
- Handle WFB session packets, data decryption, and FEC recovery.
- Parse RTP and depacketize H.264/H.265 into Annex-B access units.
- Build adaptive-link feedback payloads and WFB uplink packets.
- Parse legacy/HT/VHT radiotap TX modes and build Realtek USB TX descriptors
for monitor-injection frames.
## Basic Receive Shape
```rust
use openipc_core::{
parse_rx_aggregate, ChannelId, FrameLayout, PipelineEvent, ReceiverPipeline,
WfbKeypair,
};
use openipc_core::realtek::RxPacketType;
fn push_transfer(
pipeline: &mut ReceiverPipeline,
transfer: &[u8],
) -> Result<Vec<Vec<u8>>, Box<dyn std::error::Error>> {
let mut frames = Vec::new();
for packet in parse_rx_aggregate(transfer)? {
if packet.attrib.pkt_rpt_type != RxPacketType::NormalRx {
continue;
}
if packet.attrib.crc_err || packet.attrib.icv_err {
continue;
}
for event in pipeline.push_80211_frame(packet.data)? {
if let PipelineEvent::VideoFrame(frame) = event {
frames.push(frame.data);
}
}
}
Ok(frames)
}
fn pipeline_from_keypair(keypair_bytes: &[u8]) -> Result<ReceiverPipeline, Box<dyn std::error::Error>> {
let keypair = WfbKeypair::from_bytes(keypair_bytes)?;
Ok(ReceiverPipeline::with_keypair(
ChannelId::default_video(),
FrameLayout::WithFcs,
keypair,
0,
)?)
}
```
The returned frame data is still encoded video. Feed it to WebCodecs, a native
decoder, a file writer, or an RTP/Annex-B bridge depending on your application.
## Crate Boundaries
`openipc-core` intentionally has no USB device ownership. Pair it with:
- `openipc-rtl88xx` for native or WebUSB Realtek adapter IO.
- `openipc-native` for a CLI-style native receive loop.
- `openipc-web` or `@openipc-rs/web` for browser/WASM applications.
## Status
The protocol pipeline has unit tests for parser, crypto, FEC, RTP, and uplink
helpers. Live radio behavior still depends on the USB driver and adapter
validation in higher-level crates.