guide me to write new access plugin

[justinliyh1]

Dear all, I want to write a new plugin that access encoded mpeg4 video. The scenario is: reading data from v4l2 then encode this data via mpeg4 hardware encoder, vlc just read these encoded video data. I think this plugin should in vlc/modules/access directory. now I have made prototyping follow v4l.c in vlc/modules/access/v4l, but it worked wrong, so pls help me~ thank you for your attention.