"invalid, non monotonically increasing dts" error while writing streams to file with ffmpeg

I was finally able to write video stream packets to a file using the function

av_interleaved_write_frame(outputContext, &packet);

But after a short period of time I got this error:

Application provided invalid, non monotonically increasing dts to muxer 
in stream 0: *numberX* >= *numberY*

Does anybody h开发者_StackOverflow社区ave any idea, what's causing this and how to fix it?

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set packet.pts to a correct value before calling av_interleaved_write_frame() it's the time stamp in which this frame is presented (e.g displayed on the screen)

this value should be strictly increasing for each packet