zmqsend for FFmpeg

编译 FFmpeg 时，配置中添加 --enable-libzmq 就可以通过 tcp 通讯给 FFmpeg 发送命令

Usage: zmqsend [-h ip:port] TARGET COMMAND ARG
  Receive commands sent through a libzmq client, and forward them to filters in the filtergraph.
  default host is localhost:5555
    The send message must be in the form:
      TARGET COMMAND [ARG]
    Depending on the result, the filter will send a reply to the client, adopting the format:
      ERROR_CODE ERROR_REASON MESSAGE

  Examples
    zmqsend hue h 90
    zmqsend hue H PI/2
    zmqsend hue s 1
    zmqsend hue b 0

    zmqsend eq contrast 0.0
    zmqsend eq brightness 1.0
    zmqsend eq saturation 1.0
    zmqsend eq gamma 1.0
    zmqsend eq gamma_r 1.0
    zmqsend eq gamma_g 1.0
    zmqsend eq gamma_b 1.0
    zmqsend eq gamma_weight 1.0

zmqsend for FFmpeg

原文：http://www.cnblogs.com/nlsoft/p/5349728.html