In addition to configuring your stream type, Prism allows you to control various characteristics of the network video stream. The Encoder settings can be found by clicking Input/Encoding at the top of the web UI.
- CODEC - Select either HEVC or H.264 compression formats.
- DEINTERLACER - The Deinterlacer converts interlaced video into progressive video before streaming, improving the appearance of video that has been scaled down from the original input resolution. In addition to supporting scaled down interlaced video, deinterlacing is also useful when streaming to the Internet or mobile devices instead of a decoder.
- RESOLUTION - Maintain the input’s native resolution (Auto), or manually enter a custom resolution (Custom).
- BITRATE SELECTION - Select from a list of bitrate figures, or manually enter a custom bitrate.
- BITRATE (kbps) - Select your stream’s target bitrate. Lower bitrates require less bandwidth and may allow for a more stable stream while higher bitrates offer better video quality, but require more network bandwidth.
- FRAME RATE SELECTION - Set the encoder frame rate to the exact figure or a fraction of the input frame rate.
- KFI MODE - Select either Key Frame Interval or Group of Pictures mode.
- KEY FRAME INTERVAL/GOP LENGTH - Adjust the amount of time between full picture refreshes (Key Frame Interval), or the amount of frames (GOP Length).
- PROFILE - High profile encoding typically gives the best image quality at a given bitrate. Main and Baseline profiles utilize slightly different features, and may be more compatible with some decoders.
- LEVEL - Adjust the encoder level values. Encoder levels address bandwidth, resolution, and memory issues received from the decoder.
- CHROMA SUBSAMPLING - Chroma Subsampling is a compression method that reduces the color information and file size in a signal in favor of luminance data and decreased bandwidth.
- BIT DEPTH - The Bit Depth setting determines how many bits are used for each color component in a video stream. 8-bit color depth is sufficient for most live streaming applications, while 10-bit color depth is required for HDR workflows or other instances where higher color resolution is required.
- BITRATE CONTROL METHOD - This option is used to define the quality and bitrate of the stream. Variable Bitrate allows the codec to modify the bitrate within a quality range according to the target bitrate. Constant Bitrate maintains the output data’s bitrate at a consistent level, regardless of the video complexity. Constant Quality maintains the quality of the video without limiting the maximum or minimum bitrates.
- MINIMUM QP/MAXIMUM QP - This setting determines the quality range when the Bitrate Control Method is set to Variable Bitrate. QP Min represents the minimum amount of compression (max quality), while QP Max represents the highest amount. Change the values only if you want to restrict the codec auto bitrate adjustment.
- ENTROPY MODE (H.264 only) - Select one of two Entropy modes. CABAC requires more power and can be set if your decoder or stream destination requires it to maintain image quality. CAVLC is less complex, but more efficient than CABAC.
- AUDIO INPUT - Configure the audio input source. Selecting Embedded allows you to enable or disable Audio bitrate selection. Selecting Disabled produces a silent stream.