ofxFfmpegRecorder2

Overview

Non-realtime video recorder using FFmpeg.

This addon is designed for offline/non-realtime rendering where frames are generated faster than realtime. Unlike ofxFFmpegRecorder, this class accepts every frame immediately without time-based throttling.

Key Differences from ofxFFmpegRecorder

1. NO TIME-BASED THROTTLING

• ofxFFmpegRecorder uses real-time clock to limit frame rate (lines 550-559)
• FfmpegRecorder accepts every frame immediately, allowing faster-than-realtime rendering

2. SIMPLIFIED API

• Focused on video-only recording (no audio support)
• Removed pause/resume functionality
• Cleaner setup with fewer parameters

3. BOUNDED QUEUE

• Uses a bounded queue (MAX_QUEUE_SIZE) to prevent memory overflow
• If queue fills up, frames are dropped with a warning
• ofxFFmpegRecorder uses an unbounded lock-free queue

4. EXPLICIT START/STOP

• setup() configures parameters
• start() begins recording and spawns writer thread
• stop() finalizes video and joins thread
• ofxFFmpegRecorder starts the thread on first addFrame() call

Usage Example

ofPixels pixels;
pixels.allocate(1920, 1080, OF_PIXELS_RGBA);

FfmpegRecorder recorder;
recorder.setup(glm::vec2(1920, 1080), 30.0f, 8000, "/opt/homebrew/bin/ffmpeg");
recorder.setOutputPath("output.mp4");
recorder.setOverWrite(true);
recorder.start();

for (int i = 0; i < 300; i++) {
    // Render frame as fast as possible
    fbo.begin();
    // ... draw content ...
    fbo.end();
    fbo.readToPixels(pixels);
    recorder.addFrame(pixels);  // Pixel format auto-detected from ofPixels type
}

recorder.stop();  // Finalizes the video

Pixel Format Auto-Detection

The input pixel format is automatically detected based on the channel count:

• OF_PIXELS_MONO (1 channel) → "gray"
• OF_PIXELS_RGB (3 channels) → "rgb24"
• OF_PIXELS_RGBA (4 channels) → "rgba"

The format is detected on the first addFrame() call. You can still manually override it by calling setInputPixelFormat() before start() if needed.

API Reference

Setup & Control

• setup(glm::vec2 videoSize, float fps, unsigned int bitrate = 8000, const std::string &ffmpegPath = "ffmpeg", size_t maxQueueSize = 120) - Configure the recorder
• start() - Start recording
• stop() - Stop recording and finalize the video file
• addFrame(const ofPixels &pixels) - Add a frame to the recording queue

Setters

• setOutputPath(const std::string &path) - Set the output file path
• setOverWrite(bool overwrite) - Enable/disable file overwriting
• setVideoCodec(const std::string &codec) - Set the video codec
• setInputPixelFormat(const std::string &format) - Manually set input pixel format
• setOutputPixelFormat(const std::string &format) - Set output pixel format

Getters

• isRecording() - Check if currently recording
• getFramesQueued() - Get the number of frames that have been queued
• getFramesWritten() - Get the number of frames that have been written to disk
• getQueueSize() - Get the current queue size
• hasError() - Check if there was an error during recording
• getErrorMessage() - Get the last error message
• getOutputPath() - Get the output file path
• getVideoCodec() - Get the video codec
• getFps() - Get the frame rate
• getVideoSize() - Get the video resolution

Requirements

• FFmpeg must be installed on your system
• Provide the path to the FFmpeg executable in the setup() call