FFmpeg.cpp

FFmpeg.cpp is a C++ wrapper for FFmpeg libraries

How To Use

Read from source

fpp::InputFormatContext source {
    "rtsp://205.120.142.79/live/ch00_0"
};
if (!source.open()) {
    return;
}
fpp::Packet packet {
    source.read();
};

Write to sink

fpp::OutputFormatContext sink {
    "filename.flv"
};
sink.copyStream(source.stream(fpp::Media::Type::Video));
if (!sink.open()) {
    return;
}
sink.write(packet);

Decoding

fpp::DecoderContext video_decoder {
    source.stream(fpp::Media::Type::Video)->params
};
for (const auto& frame : video_decoder.decode(packet)) {
    ...
}

Encoding

fpp::EncoderContext video_encoder {
    sink.stream(fpp::Media::Type::Video)->params
};
for (const auto& packet : video_encoder.encode(frame)) {
    ...
}

Rescaling

fpp::RescaleContext rescaler {{
    source.stream(fpp::Media::Type::Video)->params
    , sink.stream(fpp::Media::Type::Video)->params
}};
const auto r_frame { rescaler.scale(frame) };

Resampling

fpp::ResampleContext resample {{
    source.stream(fpp::Media::Type::Audio)->params
    , sink.stream(fpp::Media::Type::Audio)->params
}};
for (const auto& r_frame : resample.resample(frame)) {
    ...
}

Linear filter

// Timelapse filter (speed x3):
const std::vector<std::string> filters {
      "select='not(mod(n,3))'"
    , "setpts=0.333*PTS"
};
fpp::LinearFilterGraph filter_graph {
      source.stream(fpp::Media::Type::Video)->params
    , filters
};
for (const auto& f_frame : filter_graph.filter(v_frame)) {
    ...
}

Complex filter

fpp::ComplexFilterGraph graph;
const std::array<std::size_t, 3> input_chain_index {
      graph.createInputFilterChain(in_audio_par[0], { "adelay=1000" })
    , graph.createInputFilterChain(in_audio_par[1], { "adelay=2000", "volume=1" })
    , graph.createInputFilterChain(in_audio_par[2], { "volume=3" })
};
const auto output_chain_index {
    graph.createOutputFilterChain(outpar, { "amix=inputs=3:dropout_transition=0" })
};
graph.link({ input_chain_index[0], input_chain_index[1], input_chain_index[2] }, { output_chain_index });
graph.init();

for (std::size_t i { 0 }; i < sources.size(); ++i) {
    ...
    graph.write(frame, input_chain_index[i]);
    ...
    for (const auto& f_frame : graph.read(output_chain_index)) {
        ...
    }
}

Examples

To see more: transcoding, screen capture, webcam recording, rtp stream, youtube stream, etc., check the examples