public static extern int avformat_open_input(AVFormatContext** ps, String filename, AVInputFormat* fmt, AVDictionary** options);
 public static extern AVInputFormat* av_input_video_device_next(AVInputFormat* d);
 public static extern AVInputFormat* av_iformat_next(AVInputFormat* f);
 public static extern int av_probe_input_buffer(AVIOContext* pb, AVInputFormat** fmt, String filename, void* logctx, int offset, int max_probe_size);
 public static extern void av_register_input_format(AVInputFormat* format);
 public static extern int avformat_open_input(AVFormatContext** @ps, [MarshalAs(UnmanagedType.LPStr)] string @url, AVInputFormat* @fmt, AVDictionary** @options);
 public static extern int av_probe_input_buffer(AVIOContext* @pb, AVInputFormat** @fmt, [MarshalAs(UnmanagedType.LPStr)] string @url, void* @logctx, uint @offset, uint @max_probe_size);
 public static extern int avdevice_list_input_sources(AVInputFormat* @device, [MarshalAs(UnmanagedType.LPStr)] string @device_name, AVDictionary* @device_options, AVDeviceInfoList** @device_list);
 public static extern AVInputFormat* av_input_audio_device_next(AVInputFormat* @d);