Preparing Content for the HyperCaster

The HyperCaster v6.1 onward has the ability to transcode virtually any video file format upon import, and convert these to the MPEG-2 Transport Stream, with MPEG-2 or H.264 Video Codecs, and MPEG-1 Layer II, AC-3, AAC, MP3 Audio Codecs required for playout. The TelVue HyperCaster transmits compressed video content over UDP packets.

The HyperCaster v4.0 and above also includes a Transmux feature, which will look for any MPEG-2 Program Stream or MP4 mux containing H.264 (including most .mov formats) video, and transmux those to the MPEG-2 Transport Stream format required to play out on the HyperCaster.

To turn on the transcoding and/or transmuxing features, navigate to Config → Content → Content, and check the options.

config transcoding

Transcoding

This will transcode imported files that are not playable either natively or with a transmux (if transmuxing is enabled). The transcoded file format will be MPEG-2 Transport with H.264/AVC video and AAC stereo audio. The source resolution will be preserved.

With transcoding turned on, the TelVue HyperCaster version 6.1 and above can import any of the following video formats:

  • Video Codecs = MPEG-1 MPEG-2 MPEG-4 H.264 H.265 ASF RM RV4 WMV1 WMV2 DIVX DV DVCPRO VC-1 FLV SWF SVQ3 CINEPACK MP1 MP2 MP3 AC3 PCM AAC JPG PNG HTML FILE WAV VP8 VP9
  • Audio Codecs = MP1 MP2 MP3 AAC PCM ADPCM WAV AC3 AC3_51 EAC3 WMA WMAV1 WMAV2 QDM2 VORBIS ALAW COOKER AMR DTS TRUEHD TTA
  • Containers = M1S MPEG1_VIDEO MP1 MP2 M2T VOB MPEG2_VIDEO MP4 MP4_MP3 M4T M4P MPEG4_VIDEO DIVX DIVX_PCM FLV SWF AVI DV ASF RM M2P MP3 AAC PCM WAV AC3 H264 H265 MATROSKA OGG WM QUICKTIME MXF GXF LXF XAVC BDAV WEBM

Transmuxing

Additionally, through the integrated Transmux feature (introduced in version 4.0), the HyperCaster can import MPEG-2 Program Streams and DVDs, as well as MP4/AVI/MOV files with the H.264 Video Codec. The HyperCaster will quickly transmux (re-multiplex) these other formats to Transport Stream on import, leaving the original video encoding intact so there is no loss of quality.

When enabling the Transmux feature, you have a choice between Constant or Variable Multiplex Rate (VMR). Unless you need a constant multiplex rate for your workflow, VMR is recommended as it results in smaller files and lower (average) multiplex rates.

If you do not have the Transmux feature enabled, the HyperCaster will still import other formats, but will show the files as unplayable. The tool tip help will display the reason why, and note that you need to enable the Transmux feature so that the file can be transmuxed to Transport Stream for compatibility.

If you do have the Transmux feature enabled, unplayable formats will still be flagged when they are first imported, but the tool tip help will show that they are waiting to be Transmuxed.

The transmux operation itself is fast, and does not require re-encoding the video stream, and also typically does not require re-encoding the audio stream. The original quality of your source video is preserved, the file is just reformatted to Transport Stream.

You can see the progress of the transmux operation in the Tasks tab.

(NOTE: If utilizing the transmux feature of the HyperCaster, first please confirm that the audio formats above are supported by the end decoding devices; IE: Set Top Boxes, TV Tuners, Other Broadcast Decode Solutions. If these audio formats are not supported, you will need to use an external file prep solution.)

The Transmux feature also makes it possible to Import a DVD.

SD content will be created at approximately 3Mbps video rate and 4Mbps multiplex. HD content will be created at approximately 6Mbps video rate and 7Mbps multiplex. The audio bitrate is 192Kbps. 608/708 Closed Captioning embedded in the video elementary stream for source files with MPEG-2 and H.264 codecs will be preserved in both transmuxed and transcoded files.

Transcode or Transmux?

If transcoding is enabled and transmuxing is disabled, then any imported file that is not playable will be transcoded. If both transmuxing and transcoding are enabled, the much faster transmux operation will always take precedence if a transmux should result in a playable file.

Note that for HyperCaster channels with native IP output, transmux and transcoding may not result in files that match your required codecs and multiplex rates. The transcoding feature is mainly a convenience for HyperCasters integrated with internal or external ProVue decoders including HyperCaster B100-SDI, HyperCaster B100-ANALOG, and HyperCaster AIO models so you can drop virtually anything into your HyperCaster and go! Where possible, importing native, compatible Transport stream files, or files that will transmux (MPEG-2 and H.264 video codecs at reasonable video bitrates, with a variety of popular container formats) will speed up your workflow.

If the HyperCaster is integrated with a TelVue Connect account, your and your contributors can upload the DVD content directly into the Connect Media Library, where it will be automatically transcoded to the proper profile and made available to distribute to your HyperCaster.

Other Considerations

As of version 4.0 the TelVue HyperCaster software supports variable mux rate Transport Streams, however other equipment in your setup may not, so you may need to investigate whether your full playout chain can support variable mux rate content.

In many Cable and IPTV environments, transport streams often must have a constant multiplex rate (note however that does not mean the video elementary stream must have a constant bit rate) and must be uniform across all encoding properties on files and streams played out. The downstream equipment receiving these streams can and often will have more stringent requirements. TelVue servers can aid with these downstream requirements by changing Program ID values as the MPEG-2 TS is transmitted. However, other requirements, such as bit rate, frame rate, profile and level, GOP structure, and more, must be set at the time of file creation or by transcoding or multiplexing.

When playing from a HyperCaster to the TelVue ProVue IP Broadcast Decoder, source file and stream encoding is much more flexible. Your schedule can mix and match MPEG-2 and H.264 video files, HD and SD, and the ProVue handles all transitions seamlessly and will automatically up and down-convert as needed based on its output settings. The TelVue ProVue decoder also support integrated, on-air graphics including Tickers, Bugs, and Snipe overlays. The TelVue ProVue is great companion to the HyperCaster in environments where you need baseband output, or require downstream graphics and branding.

CableLabs and ATSC

Two common standards that broadcast video equipment will adhere to are the CableLabs set of specifications for VOD, and the ATSC broadcast specifications. If your downstream equipment requires your files to adhere to either specification, you should select a program that the provider has verified is compliant to these specifications. If your downstream equipment does not require these particular specifications, you may be able to use any of the programs discussed in this section that are listed as HyperCaster compatible.

H.264

The TelVue HyperCaster is optionally capable of sending Transport Streams that use the H.264 video codec. However, no specific sub-standard similar to the CableLabs or ATSC standards has yet emerged for H.264 settings. Most systems using H.264 will have specific requirements for things such as profile, level and bit-rate. All of the transcoding and multiplexing programs mentioned below are capable of working with Transport Streams that include H.264, though this sometimes requires an upgraded version of the utility. If you are working with H.264 video, you should start from the Transport Stream presets provided in the transcode programs below and then tailor it to your system’s specific requirements.

in Content ManagementHC User Manual

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