GStreamer UDPSink blocksize属性不工作？

我正在使用GStreamer并使用此管道发送音频：

gst-launch-1.0-v filesrc location=soundfile.mp3！疯狂的音频转换！音频/x-raw，布局=交错，格式=F32LE，通道=2！udpsink blocksize=512端口=5005主机=127.0.0.1

但是，

blocksize

似乎根本不起作用。这是udpsink的单据，可由

gst inspect udpsink

访问：

Element Properties:
  name                : The name of the object
                        flags: readable, writable
                        String. Default: "udpsink0"
  preroll-queue-len   : Number of buffers to queue during preroll
                        flags: readable, writable
                        Unsigned Integer. Range: 0 - 4294967295 Default: 0 
  sync                : Sync on the clock
                        flags: readable, writable
                        Boolean. Default: true
  max-lateness        : Maximum number of nanoseconds that a buffer can be late before it is dropped (-1 unlimited)
                        flags: readable, writable
                        Integer64. Range: -1 - 9223372036854775807 Default: -1 
  qos                 : Generate Quality-of-Service events upstream
                        flags: readable, writable
                        Boolean. Default: false
  async               : Go asynchronously to PAUSED
                        flags: readable, writable
                        Boolean. Default: true
  ts-offset           : Timestamp offset in nanoseconds
                        flags: readable, writable
                        Integer64. Range: -9223372036854775808 - 9223372036854775807 Default: 0 
  enable-last-buffer  : Enable the last-buffer property
                        flags: readable, writable
                        Boolean. Default: true
  last-buffer         : The last buffer received in the sink
                        flags: readable
                        MiniObject of type "GstBuffer"
  blocksize           : Size in bytes to pull per buffer (0 = default)
                        flags: readable, writable
                        Unsigned Integer. Range: 0 - 4294967295 Default: 4096 
  render-delay        : Additional render delay of the sink in nanoseconds
                        flags: readable, writable
                        Unsigned Integer64. Range: 0 - 18446744073709551615 Default: 0 
  throttle-time       : The time to keep between rendered buffers (unused)
                        flags: readable, writable
                        Unsigned Integer64. Range: 0 - 18446744073709551615 Default: 0 
  bytes-to-serve      : Number of bytes received to serve to clients
                        flags: readable
                        Unsigned Integer64. Range: 0 - 18446744073709551615 Default: 0 
  bytes-served        : Total number of bytes sent to all clients
                        flags: readable
                        Unsigned Integer64. Range: 0 - 18446744073709551615 Default: 0 
  sockfd              : Socket to use for UDP sending. (-1 == allocate)
                        flags: readable, writable
                        Integer. Range: -1 - 2147483647 Default: -1 
  closefd             : Close sockfd if passed as property on state change
                        flags: readable, writable
                        Boolean. Default: true
  sock                : Socket currently in use for UDP sending. (-1 == no socket)
                        flags: readable
                        Integer. Range: -1 - 2147483647 Default: -1 
  clients             : A comma separated list of host:port pairs with destinations
                        flags: readable, writable
                        String. Default: "localhost:4951"
  auto-multicast      : Automatically join/leave the multicast groups, FALSE means user has to do it himself
                        flags: readable, writable
                        Boolean. Default: true
  ttl                 : Used for setting the unicast TTL parameter
                        flags: readable, writable
                        Integer. Range: 0 - 255 Default: 64 
  ttl-mc              : Used for setting the multicast TTL parameter
                        flags: readable, writable
                        Integer. Range: 0 - 255 Default: 1 
  loop                : Used for setting the multicast loop parameter. TRUE = enable, FALSE = disable
                        flags: readable, writable
                        Boolean. Default: true
  qos-dscp            : Quality of Service, differentiated services code point (-1 default)
                        flags: readable, writable
                        Integer. Range: -1 - 63 Default: -1 
  send-duplicates     : When a distination/port pair is added multiple times, send packets multiple times as well
                        flags: readable, writable
                        Boolean. Default: true
  buffer-size         : Size of the kernel send buffer in bytes, 0=default
                        flags: readable, writable
                        Integer. Range: 0 - 2147483647 Default: 0 
  host                : The host/IP/Multicast group to send the packets to
                        flags: readable, writable
                        String. Default: "localhost"
  port                : The port to send the packets to
                        flags: readable, writable
                        Integer. Range: 0 - 65535 Default: 4951 

这已经有点令人困惑，因为

blocksize

的默认值同时列为0和4096。然而，它似乎是4096，因为这是我的UDP数据包大小，无论我对

blocksize

使用什么值。更令人困惑的是，我在网上几乎找不到任何地方提到

blocksize

属性，即使是在GStreamer自己的文档中：

---

提到的唯一属性是

主机

和

端口

。

blocksize

是否已被弃用？如果是这样，有没有办法控制每个UDP数据包中发送的数据量？我曾尝试在RTP中使用mtu属性，但运气不佳（请参见此处），对此我有些不知所措。

当您在元素上使用gstinspect时，它会显示所有属性—不仅来自特定元素，还来自其父元素。这才是真正的预期行为

UdpSink

实际上只有

host

和

port

属性。父级-

GstMultiUDPSink

有更多

您可以在GStreamer文档中以树的形式找到继承链（对象层次结构段落）。不幸的是，并不是所有的链接都正常工作，所以最好为父元素搜索适当的链接

好，回到问题，您提到的

blocksize

是的属性，描述为：

在拉取模式下操作时要拉取的字节数。 标志：读/写

默认值：4096

所以它定义了它将从上游元素中提取多少数据。它不会影响UDP数据包。您可能要查找的是以下属性的

缓冲区大小

：

“缓冲区大小”gint 内核发送缓冲区的大小（以字节为单位），0=默认值

标志：读/写

允许的值：>=0

默认值：0