Function sam3_decode_video_frame

sam3.cpp:12288–12331

}

sam3_image sam3_decode_video_frame(const std::string& video_path, int frame_index) {
    sam3_image img;

    // Use ffmpeg to extract a single frame as raw RGB (frame-accurate)
    char cmd[1024];
    snprintf(cmd, sizeof(cmd),
             "ffmpeg -nostdin -loglevel error -i \"%s\" "
             "-vf \"select=eq(n\\,%d)\" -vsync vfr -frames:v 1 "
             "-f rawvideo -pix_fmt rgb24 pipe:1 2>%s",
             video_path.c_str(), frame_index, SAM3_NULL_DEV);

    // First, get dimensions
    char info_cmd[1024];
    snprintf(info_cmd, sizeof(info_cmd),
             "ffprobe -v error -select_streams v:0 "
             "-show_entries stream=width,height -of csv=p=0 \"%s\" 2>%s",
             video_path.c_str(), SAM3_NULL_DEV);
    FILE* fp = popen(info_cmd, SAM3_POPEN_READ);
    if (!fp) return img;
    int w = 0, h = 0;
    if (fscanf(fp, "%d,%d", &w, &h) != 2) {
        pclose(fp);
        return img;
    }
    pclose(fp);

    img.width = w;
    img.height = h;
    img.channels = 3;
    img.data.resize(w * h * 3);

    fp = popen(cmd, SAM3_POPEN_READ);
    if (!fp) {
        img.data.clear();
        return img;
    }
    size_t nread = fread(img.data.data(), 1, img.data.size(), fp);
    pclose(fp);
    if (nread != img.data.size()) {
        img.data.clear();
    }

    return img;
}

sam3_video_info sam3_get_video_info(const std::string& video_path) {
    sam3_video_info info;