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We are preparing a bunch of 10secs video bites that we hope to be picked up by news media outlets as supplemental footage for news reports.

Could anyone suggest the best specs to export the clips as before sending the links to download in our media release?

Was thinking a ProRes plus a high bitrate MP4 might suit?

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ABC, NBC, Comcast and others all have their own specs. What I've found is that 1080 progressive MP4 (h.264) at 29.97 fps (some rare cases need 59.94), with audio between 192-256 Kbps, usually does the trick. You'd obviously edit in ProRes, but to submit that codec to the stations is overkill. Some outlets will even reject specs that don't conform exactly to their specifications during the upload process to their FTP.

  • Thanks for that - is there a safe video bitrate range for the MP4? – alexh May 3 '16 at 23:57
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    I am looking at the Comcast spec sheet now and for h.264 mp4 they recommend VBR 8-50 Mbps. Though this particular outlet does accept ProRes 422 with a VBR of 40-220 Mbps. But, ProRes is probably overkill :) – A.J. Hernandez May 4 '16 at 1:02
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Getting a file format that works for everyone is very complicated. However, if you are are trying for network news, it is safe to use MPEG-2 TS 1080i29.97 (CBS, NBC, CNN) or 720p59.94 (ABC, Fox) at CBR 50Mbps, 15/3 closed GOP. Audio should be 48kHz PCM.

Local stations will accept MP4s, but you likely won't be happy with the results once it gets to air. The same goes for 1080p and 24fps flavors. Be especially careful that you have not mixed frame rates on your timeline. Pre-convert any elements that are not in the target frame rate before adding them to the timeline.

For local stations, it may be best to contact them individually. It often helps to ask if they will be transcoding an MP4 to another format and if you can just provide that format.

Be careful of any spec sheets you find publicly accessible. They are generally written for commercial copy and not for contribution content. There may be differences.

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Over-the-air broadcast stations in the U.S. may not transmit more than about 19 Mbps. This number depends on whether a station has digital subchannels. They are confined to the same 6 MHz RF-channel bandwidth they have been since the dawn of TV. Anything over 19 Mbps is definitely overkill. The station will likely transcode your footage to a format suitable to them depending on whether they need 1080i or 720p. Best to contact the individual stations if possible.

As of 2018, just about all broadcast TV stations still transmit MPEG-2, even though the ATSC spec now allows for H.264. Audio is always AC3 stereo. 192 kHz is a good audio bit rate for broadcast TV.

This is all going to change with ATSC 3.

  • I disagree that "anything over 19 Mbps is definitely overkill." Many stations routinely request 35 or 50 Mbps files. Many, but obviously not all, want the best quality/size compromise source file they can have since there will be multiple codec cycles before the spot reaches the viewer. Conversely, very few stations and almost no cable systems want to receive an AC3 encoded file. – Michael Liebman Aug 4 '18 at 15:52
  • What audio do stations prefer to receive if not AC3 and why? What do they ultimately broadcast? – chris319 Aug 5 '18 at 21:32
  • They do ultimately broadcast AC3. Most want linear PCM, though some take AAC and MP2, for submissions. AC3 was designed as a "last mile" codec and doesn't do well with multiple codec cycles. It is also much easier to distribute and monitor discrete 5.1 audio inside a plant. – Michael Liebman Aug 6 '18 at 22:22
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I’d sub prores for dnxhd. Not everyone is running a Mac based workflow or has a prores license with their windows one. The various standards of prores proxy lt etc roughly equal the numbers in dnxhd the lowest being a proxy the next an lt and so on. Depending on the station you could get away with an LT quality export if your uploading to the stations. I’ve used it as a broadcast codec befoe with out issue.

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