FFmpeg Constant UDP Output

By default ffmpeg writes to the socket as soon as new data is available.  This leads to traffic bursts which may cause the receiver buffer to overflow or underflow. Example for a 720p @ 2500 kbps CBR MPEG-2 transport stream: ffmpeg -re -i <input> -s 1280x720 -r 24 -c:v libx264 -x264opts nal-hrd=cbr:force-cfr=1 \ -b:v 2300k -minrate 2300k … Continue reading FFmpeg Constant UDP Output

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FFmpeg H.264 Constant Bitrate (CBR) Encoding

Example command using a single-frame VBV: ffmpeg -i <input> -r 25 -c:v libx264 -x264opts nal-hrd=cbr:force-cfr=1 -b:v 2500k -minrate 2500k -maxrate 2500k -bufsize 100k output.ts where: nal-hrd=cbr set the hypothetical reference decoder (HRD) to CBR and pack the bitstream to the specified bitrate force-cfr=1 force constant framerate timestamp generation -b:v the video bitrate -minrate -maxrate same … Continue reading FFmpeg H.264 Constant Bitrate (CBR) Encoding

Enabling Constant Bitrate Encoding (CBR) in Wowza Transcoder

The Wowza Trasncoder uses the MainConcept SDK. To check the encoder capabilities enable the logVideoEncodingParameters option in <Encode><Properties> the section of the transcoder template (WowzaStreamingEngine/transcoder/templates): <Property> <Name>logVideoEncodingParameters</Name> <Value>true</Value> <Type>Boolean</Type> </Property> Restart the application to apply the new changes. The supported bitrate modes are listed in the Wowza access log: # long: bit_rate_mode: bit rate stuff: 0=H264_CBR, 1=H264_CQT, 2=H264_VBR … Continue reading Enabling Constant Bitrate Encoding (CBR) in Wowza Transcoder