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When OpenH264 codec is used for transcoding, it is possible to change bitrate of mixer output stream with the following parameter in flashphoner.properties file

mixer_video_bitrate_kbps=2000

By default, mixer output stream bitrate is set to 2 Mbps. If a channel bandwith between server and viewer is not enough, bitrate can be reduced, for example

encoder_priority=OPENH264
mixer_video_bitrate_kbps=1500

If picture quality with default bitrate is low, or distortion occurs, it is recommended to rise mixer outout stream bitrate to 3-5 Mbps

encoder_priority=OPENH264
mixer_video_bitrate_kbps=5000

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By default, mixer output stream sound is encoded to Opus with sample rate 48 kHz. These settings may be changed using the parameters in  in flashphoner.properties file. For example, to use mixer output stream in SIP call the following value can be set:

audio_mixer_output_codec=pcma
audio_mixer_output_sample_rate=8000

In this case, sound will be encoded to PCMA (alaw) with sample rate 8 kHz.

Using custom losless videoprocessor for incoming streams handling

To handle mixer incoming streams, if additional bufferizing or audio and video tracks syncronizing is required for example, the custom losless videoprocessor may be used. This feature is enabled with the following parameter in flashphoner.properties file

mixer_lossless_video_processor_enabled=true

The maximum size of mixer buffer in milliseconds is set with this parameter

mixer_lossless_video_processor_max_mixer_buffer_size_ms=200

By default, maximum mixer buffer size is 200 ms. After filling this buffer, the custom losless videoprocessor uses its own buffer and waits for mixer buffer freeing. The period of mixer buffer checking is set in milleseconds with this parameter

mixer_lossless_video_processor_wait_time_ms=20

By default, the mixer buffer checking period is 20 ms.

Note that usng the custom losless videoprocessor may degrade realtime perfomance.

Quick manual on testing

1. For this test we use:

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