Ever felt like streaming software should do that one weird trick but couldn’t find a plugin? Welcome to the Wild West of OBS plugin development—where C++ wranglers build custom solutions while dodging compiler errors like tumbleweeds. Let’s saddle up and build something that’d make even a cowboy streamer tip their hat!
Why Build OBS Plugins?
OBS Studio operates like a digital swiss army knife for streamers, but sometimes you need a chainsaw attachment. Native C++ plugins (unlike scripted ones) offer raw performance for real-time video processing, custom capture sources, or hardware integration. Think of them as surgical tools versus Lua/Python’s duct tape solutions.
Pre-Requisites: Gear Up Before the Shootout
- C++ Proficiency: You’ll need intermediate knowledge (classes, pointers, CMake)
- OBS Source Code: Clone from OBS GitHub
- Plugin Template: Grab the official obs-plugintemplate
- Build Tools:
- Windows: Visual Studio 2022 (MSVC)
- macOS: Xcode + Homebrew
- Linux: GCC/Clang + CMake
git clone --recursive https://github.com/obsproject/obs-plugintemplate.git
cd obs-plugintemplate && mkdir build && cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
cmake --build . --config Release
Anatomy of an OBS Plugin: Dissecting the Beast
Plugins consist of four key components:
src/your-plugin-name.cpp
: Core logic (e.g., video processing)UI/config-dialog.cpp
: Settings interface (Qt widgets)CMakeLists.txt
: Build configurationdata/your-plugin-name.json
: Metadata (name, version, etc.) Here’s how they interact:
Building Your First Plugin: A “Hello World” with Attitude
Let’s create a color fade filter that transitions scenes like a 90s TV show.
Step 1: Initialize plugin properties
Add this to src/your-plugin.cpp
:
struct fade_filter {
obs_source_t *source;
float fade_level = 0.0f;
};
static const char *fade_get_name(void *) {
return "Disco Fade Filter";
}
Why obs_source_t
? It’s the OBS equivalent of a Swiss Army knife handle—attaches to any video source.
Step 2: Render the fade effect
Override the video_render
function:
void fade_video_render(void *data, gs_effect_t *) {
auto filter = static_cast<fade_filter*>(data);
uint32_t color = 0xFFFFFF | (uint8_t(filter->fade_level * 255) << 24);
obs_source_draw(filter->source, color, false);
}
Step 3: Connect to Qt GUI
In UI/config-dialog.cpp
, add a slider:
QSlider *fadeSlider = new QSlider(Qt::Horizontal);
QObject::connect(fadeSlider, &QSlider::valueChanged, [](int value) {
obs_data_set_double(settings, "fade_level", value / 100.0);
});
Debugging: When Your Plugin Plays Dead
- Common Pitfalls:
- DLL Hell: Ensure plugin and OBS use same CRT (static link
/MT
) - Qt Version Mismatch: Match Qt versions between OBS and your plugin
- Memory Leaks: Use
OBS_DATA
macros for auto-cleanup Pro Tip: Load your plugin via OBS’ Scripting Console (View > Scripting
) for instant error logs. If it crashes, pretend it’s a “performance art installation”.
- DLL Hell: Ensure plugin and OBS use same CRT (static link
Advanced Sorcery: Where to Go Next
- Hook into OBS Events:
signal_handler_connect(obs_get_signal_handler(), "source_activate",
[](calldata_t *data) { /* React when source goes live */ });
- Hardware Acceleration: Use
libobs/graphics/libd3d11.h
for GPU effects - Distribute Like a Pro:
- Package as
.obsplugin
bundle (plugin DLL + data folder) - Host on GitHub with GPLv2 license
- Package as
Final Showdown: Why This is Worth the Effort
Building OBS plugins feels like teaching a robot to juggle chainsaws—terrifying but spectacular when it works. Your reward? Streamers worldwide using your creation while you mutter “I made that glitch effect during a caffeine binge”. Ready to ride? The OBS Forum is your saloon for troubleshooting. Now go build something that’ll make even Shroud wonder, “How’d they do that?” 🤠