open()

bool MayaFlux::IO::FFmpegCameraReader::open ( const CameraConfig &  config )

overridevirtual

Open a camera device using the supplied config.

Parameters

config

Device name, resolution hint, fps hint, format override.

Returns

True on success.

Implements MayaFlux::IO::CameraSource.

Definition at line 111 of file FFmpegCameraReader.cpp.

{
    close();
 
    const std::string fmt_name = config.format_override.empty()
        ? std::string(CAMERA_FORMAT)
        : config.format_override;
 
    const std::string input_format = config.input_format.empty()
        ? std::string(PREFERRED_INPUT_FORMAT)
        : config.input_format;
 
    constexpr std::array<OpenHints, 4> ladder { {
        { .format = true, .size = true, .fps = true },
        { .format = false, .size = true, .fps = true },
        { .format = false, .size = true, .fps = false },
        { .format = false, .size = false, .fps = false },
    } };
 
    m_requested_pixel_format = config.pixel_format;
 
    for (size_t step = 0; step < ladder.size(); ++step) {
        const OpenHints& hints = ladder.at(step);
        if (hints.format && input_format.empty())
            continue;
 
        AVDictionary* opts = build_options(config, input_format, hints);
        const bool opened = m_demux->open_device(config.device_name, fmt_name, &opts);
        av_dict_free(&opts);
 
        if (!opened) {
            m_last_error = "Device open failed: " + m_demux->last_error();
            continue;
        }
 
        if (!m_video->open_device(*m_demux,
                hints.size ? config.target_width : 0,
                hints.size ? config.target_height : 0,
                config.pixel_format)) {
            m_last_error = "Video stream open failed: " + m_video->last_error();
            m_demux->close();
            continue;
        }
 
        m_sws_buf.clear();
        m_scaler_ready = false;
 
        if (step > (input_format.empty() ? 1U : 0U)) {
            MF_WARN(Journal::Component::IO, Journal::Context::FileIO,
                "FFmpegCameraReader::open: '{}' did not accept the requested mode, "
                "opened with fallback step {}",
                config.device_name, step + 1);
        }
 
        MF_INFO(Journal::Component::IO, Journal::Context::FileIO,
            "FFmpegCameraReader: opened '{}' via {}: {}x{} @{:.1f}fps (scaler deferred)",
            config.device_name, fmt_name,
            m_video->width, m_video->height, m_video->frame_rate);
 
        return true;
    }
 
    MF_ERROR(Journal::Component::IO, Journal::Context::FileIO,
        "FFmpegCameraReader::open: {}", m_last_error);
    return false;
}

References close(), MayaFlux::IO::CameraConfig::device_name, MayaFlux::Journal::FileIO, MayaFlux::IO::CameraConfig::format_override, MayaFlux::IO::CameraConfig::input_format, MayaFlux::Journal::IO, m_demux, m_last_error, m_requested_pixel_format, m_scaler_ready, m_sws_buf, m_video, MF_ERROR, MF_INFO, MF_WARN, MayaFlux::IO::CameraConfig::pixel_format, MayaFlux::IO::CameraConfig::target_height, MayaFlux::IO::CameraConfig::target_width, and MayaFlux::IO::U.

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