Codecs and file format compatibility

Pearl supports the following video and audio codecs.

Supported video codes

Value Description
H.264 H.264 is the default video codec configured for the channels on Pearl. This codec provides high quality video while using low bandwidth and is the preferred codec to use with the system.
Motion JPEG Motion JPEG is suitable for live streaming and video; however, you can experience low quality images while using high bandwidth. Motion JPEG does not support audio.

Supported audio codecs and bitrate guidance

Value Description
AAC

AAC is comparable to MP3 and may even provide better sound quality at a similar sample bitrate. Supported sampling bitrate values are: 16, 22, 44 and 48K kHz.

Setting the channel bitrate to match the audio source's bitrate provides the best sound quality and avoids audio resampling. Most digital signals (HDMI or SDI sources) use 48 kHz. Most digital signals (HDMI or SDI sources) use 48 kHz audio. For analog signals, 44 kHz provides a good quality audio sample.

The maximum bitrate for mono encoding of a 44 kHz signal is 264 kbps. For stereo, 320 kbps is supported. Note that lower bitrates (e.g. 32 kbps) with a 44 kHz signal may result in distorted audio.

MP3

MP3 provides a common audio format for audio storage. Supported sampling bitrate values are: 22 kHz, 44 kHz and 48 kHz.

Setting the channel bitrate to match the audio source's bitrate provides the best sound quality and avoids audio resampling. Most digital signals (HDMI or SDI sources) use 48 kHz. For analog signals, 44 kHz provides a good quality audio sample.

Web browsers that use Flash (FLV) do not support 48 kHz MP3 audio. When selecting this encoding, you must use a web browser that supports HTML5 or a media player to preview your channel.

PCM

Pulse Code Modulation (PCM) is a standard for digital audio in computer and other devices such as, digital telephone systems.

Setting the level to match the audio source's level provides the best sound quality and avoids audio resampling. Most digital signals (HDMI or SDI sources) use 48 kHz audio. For analog signals, 44 kHz provides a good quality audio sample.

The Flash (FLV) plugin must be installed for your web browser to play back audio that's encoded as PCM. Web browsers that use Flash (FLV) do not support 48 kHz PCM audio.

 

Format compatibility

Not all streaming and recording protocols support all combinations of video and audio codecs. The following table lists any video/audio codec compatibility considerations for the supported streaming formats on Pearl.

Video/audio codecs and formats for streaming

Video Codec selected Audio Codec selected RTSP FLV MPEG-TS MJPEG
H.264 No audio codec ü ü ü  
H.264 PCM ü ü    
H.264 MP3 ü ü ü  
H.264 AAC ü ü ü  
MJPEG No audio codec       ü

The following table displays the compatibility between the video/audio codecs and the supported recording formats.

Video/audio codecs and formats for recording

Video Codec selected Audio Codec selected MP4 and MP4-Fragmented AVI MOV MPEG-TS
H.264 No audio codec ü ü ü ü
H.264 PCM ü ü ü  
H.264 MP3 ü ü ü ü
H.264 AAC ü ü ü ü
MJPEG No audio codec ü ü ü ü