wireshark具有这个功能，但是并不适合做批量执行。
下面的方案比较适合批量执行。
# 1. 安装依赖
yum install gcc libpcap-devel libnet-devel sox -y
# 2. 克隆源码
git clone https://github.com/wangduanduan/rtpsplit.git
# 3. 切换目录
cd rtpsplit
# 4. 编译可执行文件
make
# 5. 将可执行文件复制到/usr/local/bin目录下
cp src/rtpbreak /usr/local/bin
# 6. 切换到录音文件的目录，假如当前目录只有一个文件
rtpbreak -r krk9hprvin1u1laqe14g-8beffe8aaeb9bf99.pcap -g -m -d ./
audio git:(edge) ✗ rtpbreak -r krk9hprvin1u1laqe14g-8beffe8aaeb9bf99.pcap -g -m -d ./
+ rtpbreak v1.3a running here!
+ pid: 1885, date/time: 01/05/2020#09:49:05
+ Configuration
+ INPUT
Packet source: rxfile 'krk9hprvin1u1laqe14g-8beffe8aaeb9bf99.pcap'
Force datalink header length: disabled
+ OUTPUT
Output directory: './'
RTP raw dumps: enabled
RTP pcap dumps: enabled
Fill gaps: enabled
Dump noise: disabled
Logfile: './/rtp.0.txt'
Logging to stdout: enabled
Logging to syslog: disabled
Be verbose: disabled
+ SELECT
Sniff packets in promisc mode: enabled
Add pcap filter: disabled
Expecting even destination UDP port: disabled
Expecting unprivileged source/destination UDP ports: disabled
Expecting RTP payload type: any
Expecting RTP payload length: any
Packet timeout: 10.00 seconds
Pattern timeout: 0.25 seconds
Pattern packets: 5
+ EXECUTION
Running as user/group: root/root
Running daemonized: disabled
* You can dump stats sending me a SIGUSR2 signal
* Reading packets...
open di .//rtp.0.0.txt
! [rtp0] detected: pt=0(g711U) 192.168.40.192:26396 => 192.168.60.229:20000
open di .//rtp.0.1.txt
! [rtp1] detected: pt=0(g711U) 10.197.169.10:49265 => 192.168.60.229:20012
* eof reached.
--
Caught SIGTERM signal (15), cleaning up...
--
* [rtp1] closed: packets inbuffer=0 flushed=285 lost=0(0.00%), call_length=0m12s
* [rtp0] closed: packets inbuffer=0 flushed=586 lost=0(0.00%), call_length=0m12s
+ Status
Alive RTP Sessions: 0
Closed RTP Sessions: 2
Detected RTP Sessions: 2
Flushed RTP packets: 871
Lost RTP packets: 0 (0.00%)
Noise (false positive) packets: 8
+ No active RTP streams
# 7. 查看输出文件
-rw-r--r--. 1 root root 185K May 1 09:22 krk9hprvin1u1laqe14g-8beffe8aaeb9bf99.pcap
-rw-r--r--. 1 root root 132K May 1 09:49 rtp.0.0.pcap
-rw-r--r--. 1 root root 92K May 1 09:49 rtp.0.0.raw
-rw-r--r--. 1 root root 412 May 1 09:49 rtp.0.0.txt
-rw-r--r--. 1 root root 52K May 1 09:49 rtp.0.1.pcap
-rw-r--r--. 1 root root 33K May 1 09:49 rtp.0.1.raw
-rw-r--r--. 1 root root 435 May 1 09:49 rtp.0.1.txt
-rw-r--r--. 1 root root 1.7K May 1 09:49 rtp.0.txt
# 8. 使用sox 转码以及合成wav文件
sox -r8000 -c1 -t ul rtp.0.0.raw -t wav 0.wav
sox -r8000 -c1 -t ul rtp.0.1.raw -t wav 1.wav
sox -m 0.wav 1.wav call.wav
# 最终合成的 call.wav文件，就是可以放到浏览器中播放的双声道语音文件
参考
rtpbreak帮助文档
Copyright (c) 2007-2008 Dallachiesa Michele <micheleDOTdallachiesaATposteDOTit>
rtpbreak v1.3a is free software, covered by the GNU General Public License.
USAGE: rtpbreak (-r|-i) <source> [options]
INPUT
-r <str> Read packets from pcap file <str>
-i <str> Read packets from network interface <str>
-L <int> Force datalink header length == <int> bytes
OUTPUT
-d <str> Set output directory to <str> (def:.)
-w Disable RTP raw dumps
-W Disable RTP pcap dumps
-g Fill gaps in RTP raw dumps (caused by lost packets)
-n Dump noise packets
-f Disable stdout logging
-F Enable syslog logging
-v Be verbose
SELECT
-m Sniff packets in promisc mode
-p <str> Add pcap filter <str>
-e Expect even destination UDP port
-u Expect unprivileged source/destination UDP ports (>1024)
-y <int> Expect RTP payload type == <int>
-l <int> Expect RTP payload length == <int> bytes
-t <float> Set packet timeout to <float> seconds (def:10.00)
-T <float> Set pattern timeout to <float> seconds (def:0.25)
-P <int> Set pattern packets count to <int> (def:5)
EXECUTION
-Z <str> Run as user <str>
-D Run in background (option -f implicit)
MISC
-k List known RTP payload types
-h This