영상처리 인터페이스 및 프로토콜 개략

 Video Source Category

Each category represents a different way of accessing video streams, depending on how the camera or source delivers its data.

Some (like Webcam & Video File) are direct video sources.

• Others (like ONVIF & IP Camera) use network streaming protocols.
• Some (like GStreamer) act as advanced video pipelines.

 

Category	What It Is	How It Works
Webcam	A directly connected USB camera or built-in laptop camera.	Uses UVC (USB Video Class) to stream video as a standard video device recognized by the OS.
Video File	A pre-recorded video file (MP4, AVI, etc.).	Loads from storage instead of a live camera feed.
Directory	A folder of images (e.g., sequential frames).	Loads each image as a frame, useful for time-lapse or batch processing.
ONVIF	A standard for network-based IP cameras.	Uses RTSP (Real-Time Streaming Protocol) over a network to stream live video.
ScreenCap	Captures the computer screen as a video stream.	Useful for screen recording or using a desktop as a virtual camera.
IP Camera	A generic network camera, not necessarily ONVIF-compliant.	Uses RTSP, HTTP, or proprietary protocols to stream video from a remote camera.
GStreamer	A multimedia processing framework for handling video/audio streams.	Can process and manipulate video before loading it into RT Studio.

 

 

Multimedia frameworks

A multimedia framework is a software library or toolkit that helps developers process, stream, capture, and render various types of media as img, video, audio.

 

A multimedia framework  provides:

Capability	Description
📥 Input handling	Read video/audio from files, cameras, microphones, streams (e.g., RTSP, HTTP, etc.)
🔄 Processing & Transcoding	Compress, decompress, encode, decode, resize, filter, convert formats
📤 Output handling	Save to file, stream over the network, render on screen/speaker
🧩 Pipeline or Plugins	Chain different operations like filters, encoders, sinks

 

Popular Multimedia Frameworks

Framework	Description
FFmpeg	Command-line tool and libraries (libav*) to encode/decode/stream/convert
GStreamer	Modular, plugin-based framework ideal for live/real-time pipelines
DirectShow	Microsoft’s multimedia framework (used in Windows Media)
VLC LibVLC	Library from VLC media player (used for playback and streaming)
MediaPipe	Google’s framework for ML-based video/audio (face detection, etc.)

 

Comparision of FFmpeg And Gstreamer

Feature	FFmpeg	GStreamer
Interface	CLI (single command)	Modular pipeline (element-based)
Use Case	Transcode, convert, stream files	Live capture, custom workflows
Latency Focus	Less low-latency friendly	Optimized for real-time use
Extensibility	Less modular	Highly modular (plugins)
Learning Curve	Simpler to get started	Steeper but more flexible

 

Streaming Protocol

 

What is HLS (HTTP Live Streaming)?

 

HLS (HTTP Live Streaming) is a media streaming protocol developed by Apple that delivers video/audio content over the internet in real time. It works by breaking video files into small segments (e.g., .ts files) and providing a master playlist file (.m3u8) that tells the client how to play them.

 

Why HLS?

• Adaptive Streaming: Adjusts video quality based on network speed.
• Low Latency: Ideal for live video streaming.
• Cross-Platform: Works on browsers, mobile devices, and smart TVs.

 

✔ Works on browsers 🌍 Supports Chrome, Firefox, Safari, mobile devices
✔ Supports adaptive streaming 📶 Adjusts quality based on network speed
✔ Easier to scale 🔄 Can serve multiple users via CDN

 

RTSP (Real-Time Streaming Protocol)

 

✔ Low latency (~2 sec) ✅ Good for real-time surveillance
❌ Not browser-friendly 🚫 Most browsers don’t support RTSP
❌ Scalability issues 🚫 Hard to handle many users at once

 

 

📌 HLS vs RTSP

 

Feature	HLS (HTTP Live Streaming)	RTSP (Real-Time Streaming Protocol)
Transport Protocol	HTTP	RTP (Real-Time Transport Protocol)
Latency	High (typically 10-30 sec)	Low (typically <2 sec)
Compatibility	Works in browsers, mobile, most devices	Requires special players (VLC, OBS, etc.)
Usage	Live video streaming over the web (e.g., YouTube, Twitch)	Surveillance cameras, CCTV, real-time applications
Segments	Converts stream into .m3u8 playlist & .ts files	Sends continuous real-time stream
Adaptive Streaming	Yes, supports multiple bitrates	No