Update README about Metacube input.

[cubemap] / README

diff --git a/README b/README
index e9520d3aec889da9e53f9bad82f69352024080c3..efcfa77f3592d123cd72f1a3d36ebe8fc3f2ceba 100644 (file)
--- a/README
+++ b/README
@@ -1,5 +1,4 @@
-Cubemap is a high-performance, high-availability video reflector,
-specifically made for use with VLC.
+Cubemap is a high-performance, high-availability video reflector.
 
 A short list of features:
 
@@ -11,8 +10,7 @@ A short list of features:
    and sending a SIGHUP; all clients will continue as if nothing had happened
    (unless you delete the stream they are watching, of course).
    Cubemap also survives the encoder dying and reconnecting.
- - Support for setting max pacing rate through the fq packet scheduler
-   (depends on Linux 3.13 or newer).
+ - Support for setting max pacing rate through the fq packet scheduler.
  - Reflects anything VLC can reflect over HTTP, even the muxes VLC
    has problems reflecting itself (in particular, FLV).
  - Multicast support, both for sending and receiving (supports only protocols
@@ -27,12 +25,21 @@ A short list of features:
 
 HOWTO:
 
-  sudo apt install libprotobuf-dev protobuf-compiler libsystemd-dev libtomcrypt-dev
+  sudo apt install libprotobuf-dev protobuf-compiler libsystemd-dev libtomcrypt-dev pkg-config
   ./configure
   make -j4
 
-If you want to use HTTP input (you probably want to), you want VLC 2.2.0
-or newer. Then start the VLC encoder with the “metacube” flag to the http
+Cubemap does not in itself understand the format of video streams;
+it requires HTTP input that is already delineated into headers and blocks,
+so that it knows what parts of the stream to skip to clients that
+connect after the stream has been. (The exception is self-synchronizing
+streams with no headers, such as MPEG-TS. These can also be sent or
+received over UDP) The input format is specific to Cubemap and is called
+Metacube (technically, Metacube2, but Metacube1 is long gone and nothing
+uses it anymore). Currently, you have three options to create Metacube
+video streams: VLC, Nageru or FFmpeg with a hack.
+
+For VLC, start the VLC encoder with the “metacube” flag to the http
 access mux, like this:
 
   cvlc [...] --sout '#std{access=http{metacube,mime=video/x-flv},mux=flv,dst=:4013/test.flv}'
@@ -40,8 +47,18 @@ access mux, like this:
 Then look through cubemap.config.sample, copy it to cubemap.config,
 compile and start cubemap.
 
-Nageru, my free video mixer, can also produce Metacube streams natively.
-See the manual at https://nageru.sesse.net/doc/ for more information.
+Nageru, my free video mixer, can also produce Metacube streams natively,
+and so can its included transcoder/remuxer Kaeru. See the manual
+at https://nageru.sesse.net/doc/ for more information.
+
+If you feel very adventurous, you can use LD_PRELOAD to load
+ffmpeg_metacube_hack.so into an FFmpeg-using binary. (This is
+experimental; native Metacube support is vastly preferred.)
+For instance, here's one way you can use the ffmpeg(1) binary
+to serve your webcam to Cubemap:
+
+  LD_PRELOAD=ffmpeg_metacube_hack.so ffmpeg -i /dev/video0 -f mpegts -listen 1 'http://[::]:9095'
+
 
 To upgrade cubemap (after you've compiled a new binary), or to pick up new
 config: