SFmpeg

A Swift wrapper for the FFmpeg API, adapted for Swift 6 strict concurrency checking with high-level abstractions for playing media files.

Educational Purpose: This project is primarily intended for learning and education. It provides a clear, Swift-idiomatic way to understand and work with FFmpeg's media processing capabilities.

Features

• Swift 6 Ready: Fully adapted to Swift 6 strict concurrency checking for safe, concurrent code
• High-Level Abstractions: Easy-to-use APIs like SFPlayerItem for playing media files without dealing with low-level FFmpeg details
• Low-Level Access: Full access to FFmpeg's C API when you need fine-grained control

Note: SFmpeg is still in development, and the API is not guaranteed to be stable. It's subject to change without warning.

Installation

FFmpeg is already included in this repository as an XCFramework (downloaded from avbuild), so no separate FFmpeg installation is required.

Swift Package Manager

SFmpeg uses SwiftPM as its build tool. To depend on SFmpeg in your project, add a dependencies clause to your Package.swift:

dependencies: [
    .package(url: "https://github.com/sunlubo/SwiftFFmpeg.git", from: "1.0.0")
]

Documentation

• API documentation

Quick Start: Playing Media Files

The high-level SFPlayerItem abstraction makes it easy to work with media files:

import SFmpeg

// Create a player item from a media file
let playerItem = try SFPlayerItem(url: "path/to/media.mp4")

// Access media information
print("Duration: \(playerItem.duration) seconds")
print("Video tracks: \(playerItem.videoTracks.count)")
print("Audio tracks: \(playerItem.audioTracks.count)")

// Decode frames for playback
while let frame = try playerItem.decodeNextFrame() {
    // Process or display the frame
}

Low-Level API Usage

For more control, you can use the low-level FFmpeg wrappers directly:

import Foundation
import SwiftFFmpeg

if CommandLine.argc < 2 {
    print("Usage: \(CommandLine.arguments[0]) <input file>")
    exit(1)
}
let input = CommandLine.arguments[1]

let fmtCtx = try AVFormatContext(url: input)
try fmtCtx.findStreamInfo()

fmtCtx.dumpFormat(isOutput: false)

guard let stream = fmtCtx.videoStream else {
    fatalError("No video stream.")
}
guard let codec = AVCodec.findDecoderById(stream.codecParameters.codecId) else {
    fatalError("Codec not found.")
}
let codecCtx = AVCodecContext(codec: codec)
codecCtx.setParameters(stream.codecParameters)
try codecCtx.openCodec()

let pkt = AVPacket()
let frame = AVFrame()

while let _ = try? fmtCtx.readFrame(into: pkt) {
    defer { pkt.unref() }

    if pkt.streamIndex != stream.index {
        continue
    }

    try codecCtx.sendPacket(pkt)

    while true {
        do {
            try codecCtx.receiveFrame(frame)
        } catch let err as AVError where err == .tryAgain || err == .eof {
            break
        }

        let str = String(
            format: "Frame %3d (type=%@, size=%5d bytes) pts %4lld key_frame %d",
            codecCtx.frameNumber,
            frame.pictureType.description,
            frame.pktSize,
            frame.pts,
            frame.isKeyFrame
        )
        print(str)

        frame.unref()
    }
}

print("Done.")