我使用ffmpeg转换视频流格式时出现问题，但是还是可以转换。
我使用的命令是：
./ffmpeg -i rtsp://admin:12345@192.168.1.55 -vcodec copy -acodec copy -s 640x480 -f flv rtmp://192.168.1.88:1935/hls/test2
出现问题：
[udp @ 0x2aabbe0] 'circular_buffer_size' option was set but it is not supported on this build (pthread support is required)
[udp @ 0x2aad6d0] 'circular_buffer_size' option was set but it is not supported on this build (pthread support is required)
[udp @ 0x2aadb80] 'circular_buffer_size' option was set but it is not supported on this build (pthread support is required)
[udp @ 0x2aadbf0] 'circular_buffer_size' option was set but it is not supported on this build (pthread support is required)
Guessed Channel Layout for Input Stream #0.1 : mono
以及
[flv @ 0x2aae900] Non-monotonous DTS in output stream 0:0; previous: 240, current: 40; changing to 240. This may result in incorrect timestamps in the output file.
[flv @ 0x2aae900] Non-monotonous DTS in output stream 0:0; previous: 240, current: 80; changing to 240. This may result in incorrect timestamps in the output file.
[flv @ 0x2aae900] Non-monotonous DTS in output stream 0:0; previous: 240, current: 120; changing to 240. This may result in incorrect timestamps in the output file.
[flv @ 0x2aae900] Non-monotonous DTS in output stream 0:0; previous: 240, current: 160; changing to 240. This may result in incorrect timestamps in the output file.
[flv @ 0x2aae900] Non-monotonous DTS in output stream 0:0; previous: 240, current: 200; changing to 240. This may result in incorrect timestamps in the output file.
详细的截图如下：
请问有人遇到过这个问题吗？谢谢了
