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In this case, buffer is cleared and goes to the PASSTHROUGH state. Even if stream delay becomes lower, buffer will remain in the state, and stream will not be buffered until publishing is stopped.

Recommended RTMP stream buffering settings for high quality publishing

The following buffering settings are recommended when publishing a high quality RTMP streams (high bitrate, HD, FullHD resolutions)

rtmp_in_buffer_enabled=true
rtmp_in_buffer_start_size=1000
rtmp_in_buffer_initial_size=3000
rtmp_in_buffer_polling_time=30
rtmp_in_buffer_max_bufferings_allowed=-1

In this case an RTMP stream published should play smoothly for viewers (if channel quality is good enough) and in mixer.

Detect stream parameters by metadata or media traffic

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