FFmpeg problems with playing a stream in openwrt

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1

i am using openwrt 21.02.5 on raspberry pi 3 B+. camera is connected with raspberry pi via ethernet. i want to recording streaming and save into raspberry pi. for that i am using ffmpeg i used this command

ffmpeg -rtsp_transport tcp -i rtsp:username:password@ip:port/live/ch00_0 -vcodec copy -acodec copy -f segment -reset_timestamps 1 -segment_time 900 -segment_format mkv -segment_atclocktime 1 -strftime 1 /root/recording/%Y%m%dT%H%M%S.mp4

but i am getting this error

[h264_v4l2m2m @ 0x2fc6f3c0] Could not find a valid device 
[h264_v4l2m2m @ 0x2fc6f3c0] can't configure decoder
 [rtsp @ 0x2fc6c360] Failed to open codec in avformat_find_stream_info 
[h264_v4l2m2m @ 0x2fc6f3c0] Could not find a valid device
 [h264_v4l2m2m @ 0x2fc6f3c0] can't configure decoder 
[rtsp @ 0x2fc6c360] Stream #0: not enough frames to estimate rate; consider increasing probesize [rtsp @ 0x2fc6c360] Could not find codec parameters for stream 0 (Video: h264, none): unspecified size Consider increasing the value for the 'analyzeduration' and 'probesize' options

but when i installed ubuntu server on same raspberry pi and run same command it works. please help me to sort this issue
ffmpeg version i used are:4.3.2, 5.1.1

2

I was also trying to figure out this .. I want to re-stream a camera so I can keep the connection opened and avoid slow detections by a cloud service .. but it seems h264 is missing somehow ...