为什么无法接收.avi视频文件的rtp流媒体？

Question

在ffmpeg streamingGuide，它写道：

ffmpeg -re -f lavfi -i aevalsrc="sin(400*2*PI*t)" -ar 8000 -f mulaw -f rtp rtp://127.0.0.1:1234 & 
ffplay rtp://127.0.0.1:1234 

我想用一个真正的视频文件，以代替人工信号。 然后我编写下面在A端：

ffmpeg -re -i outputFile.avi -f mulaw -f rtp rtp://127.0.0.1:1234 

似乎它是工作： 帧信息被计数。以下是在端部上的终端A信息：

frame= 309 fps= 29 q=31.0 Lsize=  931kB time=00:00:10.30 bitrate= 740.8kbits/s  video:922kB audio:0kB subtitle:0 global headers:0kB muxing overhead 1.030813% 

当端A上的框架仍在计数（未完成），我在终端B键入以下：

ffplay rtp://127.0.0.1:1234 

但它确实不行： 错误信息是：

[udp @ 0x7fb370001500] bind failed: Address already in useB f=0/0 
rtp://127.0.0.1:1234: Input/output error 

为什么？

[更新1]在从卡米尔Goudeseune 我用foo.sdp指令
用于ffmpeg的终端的输入是：

的ffmpeg -re -i out.avi -f mulaw -f RTP RTP：//127.0.0.1：1235

为ffplay的终端是：

ffplay -i foo.sdp

ffplay终端显示很多错误，没有图像。

libpostproc 52. 2.100/52. 2.100 
[sdp @ 0x7fafdc0008c0] Undefined type (30) 0KB sq= 0B f=0/0 
[sdp @ 0x7fafdc0008c0] nal size exceeds length: 25453 86 0B f=0/0 
[sdp @ 0x7fafdc0008c0] Consumed more bytes than we got! (-25367) 
[sdp @ 0x7fafdc0008c0] nal size exceeds length: 25453 86 
[sdp @ 0x7fafdc0008c0] Consumed more bytes than we got! (-25367) 
[sdp @ 0x7fafdc0008c0] Unhandled type (27) (See RFC for implementation details 
[sdp @ 0x7fafdc0008c0] Undefined type (31) 0KB sq= 0B f=0/0 
[sdp @ 0x7fafdc0008c0] Unhandled type (27) (See RFC for implementation details 
[sdp @ 0x7fafdc0008c0] nal size exceeds length: 62414 6130B f=0/0 
[sdp @ 0x7fafdc0008c0] Consumed more bytes than we got! (-61801) 
[sdp @ 0x7fafdc0008c0] nal size exceeds length: 62414 613 
[sdp @ 0x7fafdc0008c0] Consumed more bytes than we got! (-61801) 
[h264 @ 0x7fafdc003020] non-existing PPS referencedq= 0B f=0/0 
[h264 @ 0x7fafdc003020] non-existing PPS 0 referenced 
[h264 @ 0x7fafdc003020] decode_slice_header error 
[h264 @ 0x7fafdc003020] Invalid mix of idr and non-idr slices 
[sdp @ 0x7fafdc0008c0] Undefined type (31) 0KB sq= 0B f=0/0 
[sdp @ 0x7fafdc0008c0] Unhandled type (29) (See RFC for implementation details 
[sdp @ 0x7fafdc0008c0] Unhandled type (26) (See RFC for implementation details 
[sdp @ 0x7fafdc0008c0] Unhandled type (27) (See RFC for implementation details 
    Last message repeated 2 times 0KB vq= 0KB sq= 0B f=0/0 
[sdp @ 0x7fafdc0008c0] Undefined type (31) 
[sdp @ 0x7fafdc0008c0] Unhandled type (26) (See RFC for implementation details 
[sdp @ 0x7fafdc0008c0] Unhandled type (25) (See RFC for implementation details 
[h264 @ 0x7fafdc003020] insane cropping not completely supported, this could look slightly wrong ... (left: 2, top: 2) 
[h264 @ 0x7fafdc003020] illegal aspect ratio 
[h264 @ 0x7fafdc003020] missing picture in access unit with size 84589 
[h264 @ 0x7fafdc003020] Partitioned H.264 support is incomplete 
[h264 @ 0x7fafdc003020] insane cropping not completely supported, this could look slightly wrong ... (left: 2, top: 2) 
[h264 @ 0x7fafdc003020] illegal aspect ratio 
[h264 @ 0x7fafdc003020] insane cropping not completely supported, this could look slightly wrong ... (left: 2, top: 2) 
[h264 @ 0x7fafdc003020] illegal aspect ratio 
[h264 @ 0x7fafdc003020] no frame! 
[h264 @ 0x7fafdc003020] RTP: missed 2563 packetsB sq= 0B f=0/0 
[sdp @ 0x7fafdc0008c0] Undefined type (30) 
    Last message repeated 1 times 
[sdp @ 0x7fafdc0008c0] Undefined type (31) 

Answer 1

而不是ffplay rtp://127.0.0.1:1235，请使用ffplay -i foo.sdp。

通过粘贴到它从下面的线SDP: ffmpeg的输出的文本创建本地文件foo.sdp，例如：

v=0 
o=- 0 0 IN IP4 127.0.0.1 
s=No Name 
c=IN IP4 127.0.0.1 
t=0 0 
a=tool:libavformat 55.2.100 
m=video 1235 RTP/AVP 96 
a=rtpmap:96 H264/90000 
a=fmtp:96 packetization-mode=1 

的.sdp文件包括RTP地址，这样你就不需要指定RTP： // ...以及。

Answer 2

ffplay rtp://127.0.0.1:1234将开始监听UDP端口1234入局RTP流量。

只有一个应用程序可以在任何给定时间监听主机上的任何给定端口。

错误“绑定失败：地址已在使用中”表示另一应用程序正在侦听端口1234。 可能你还在运行测试脚本？

要么停止阻塞端口的应用程序，要么使用不同的端口。