interrogations around VLC mosaic

[FredB]

Hello everyone,

I have a project this summer around VLC and MVC (Multiview VideoCoding).
I am using several USB and firewire cameras to get a multiview input stream and one output which contains all pictures.

I am using a third party MVC encoder.

I have been advised to use VLM + mosaic. I read and tried to understand source
code of the files modules/stream_out/bridge.c, modules/stream_out/mosaic-bridge.c
and modules/video_filter/mosaic.c.
I would like to have some precisions:
- What is the block_t structure utility?
- What are the i_sar_num and i_sar_den fields meanings in sout_stream_sys_t structure?
- What is the picture_ring aim?
- How does generally an encoder get pictures to transcode?

Frederic