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When a TV station commissions/buys/rents a TV show, in what format does it get sent to them? I can't imagine it's film that they'd have to transfer themselves, but it should be clearly a better quality than you could buy the shows as home media (as a CD/DVDs or Blu-Rays), even decades later.

What could be that format?

Why has this media format never been made into public/consumer models?

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    "it's clearly a better quality than you could buy the shows on to watch at home" in Australia i would disagree, Digital Free-to-air TV for Sword Art Online and K-On are lower quality than what i can get from DVD and Bluray and this is through set top box connected to HDMI set at 1080p – Memor-X Jul 21 '17 at 1:22
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    @Memor-X: a Finnish network broadcast Twin Peaks from which was clearly a VHS source in 2007. Had tracking artifacts and all that crap. I lol'd and bought the remastered DVD boxes. – unperson325680 Jul 21 '17 at 8:37
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    @Memor-X The quality broadcast is not necessarily the same as the material came in. – Thorbjørn Ravn Andersen Jul 21 '17 at 19:16
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    Indeed, particularly in an age of statistically multiplexed digital telly, there is a vicious trade between the number of channels you can fit in a mux and the average bitrate you can allocate to each channel. If you are running a channel on a budget for a niche market, lower data rates can be very much worth while (Especially if your production values are less then stellar to begin with). – Dan Mills Jul 21 '17 at 20:26
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    You can read Netflix's Production and Post-Production Requirements, which they make public. They're not a TV station, but they do commission/buy/"rent" shows and movies. Other TV stations and networks likely have their own requirements. – Cornstalks Jul 22 '17 at 16:16
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TL;DR

While it varies from station to station, it is common to receive or ingest the footage by receiving on satellite and recording it for later usage.

Where possible, the TV station will accept the media files from the production house or a distribution service directly. In this case, the media is usually in the MXF or MOV file formats.

The resolution is usually 1280x720 or 1920x1080, with a higher bit-rate ranging between 30 and 100 Mbps.

The only major difference between the consumer deliverable and the format the station has is the bit-rate. The TV station has equipment that can handle the larger files, and has a larger data storage capacity than most normal households. However, a well encoded Blu-ray will contain a close copy of the file the station receives, with an encoded bit-rate between 15 and 45 Mbps.

The main reason for the difference is bandwidth. One 24 minute episode at a bit rate of 145 Mbps stored in uncompressed MXF can be as large as 29 GB. Unfortunately, that has to be compressed in order to get it out to the millions of people that TV stations service.


There isn't an established format that all TV stations receive. It largely depends on the format that can be provided to the station, and what the station is setup to accept regarding equipment.

As Scotty Parker mentioned, a lot of the content is ingested into the studio via satellite. meaning, it's simply recorded as it's airing, like a fancy DVR and a dish that's bigger than average. When this is the case, the recorded format is usually as high as it can be, which is hopefully in most cases HD at 1280x720, or FHD at 1920x1080.

However, an increasingly large number of stations use content that is acquired directly from the production house. Meaning that the company who produced and/or edited the show will provide the media directly to the station airing it. In many cases this is a very high bit-rate, high resolution file. Something akin to Avid's DNxHD format (such as DNxHD145 or 175), or Apple ProRes, or Sony's XDCAM. But despite the higher-than-average bitrate of the file, the resolution is rarely anything higher than 1080p.

Unless you're the editor, and you'd be working with a 1080p file at a bit-rate of 145 or 175 Mbps.

But these formats are not secret, or kept from the general public. You can have the same formats TV stations use.

For example: File based workflows (where the production house turns over the raw media directly), the file would most likely be in the MOV or MXF formats. These files are normally encoded at a bit rate of somewhere between 30 and 50 Mbps (hopefully), and a have resolution between 720 and 1080.

Neither of these file types are hard to come by, and in fact, the MXF file type is listed as a SMPTE standard (SMPTE 377M). But how convenient would it be to sell you a show and make you download a 28GB file or a 32GB USB drive with a single episode of Game of Thrones?

So, it's made available to everybody in a compressed, but still very high quality format: Blu-ray.

These Blu-ray's are normally encoded at a 15-30 Mbit bit-rate, which although less than the raw MXF, is still very high.

Or you could download a slightly more compressed version from some website, or a streaming/OTT service (Apple TV, Netflix, etc).

Source: I work at a TV station.

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    I would gladly get the 32 GB files! That said: Why do they distribute these massive files, if most are then severly compressed when aired? The bitrates I seem to get when I look at TV are very low, and they are one of the reasons I stoped watching TV, prefering to wait untill I can get a blu-ray version of the content. If you are going to display a heavily compressed version, why don't you just store it as such? I imagine with the amount of redundancy and such storing a 32GB file will take a lot of space. – Joren Vaes Jul 21 '17 at 17:55
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    In set-top cable installations, the provider will reallocate bandwidth across channels dynamically -- spending more bits on the big game than on daily soap operas one day, then spending more bits on the season premiere of a big drama than a little league game the next, for example -- so it makes sense to distribute the highest quality version even if it might be re-encoded at a lower quality for broadcast. – Russell Borogove Jul 21 '17 at 18:03
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    Then you must have a lot of hard drives @JorenVaes! Sorry too hear that your TV experience was that bad! The TV stations like the larger files because it gives them a bit of freedom. For example, if they can provide an internet streaming solution at a higher bit rate than they can provide on OTA TV, or satellite, having the highest quality file lets them compress and convert as they need to. And yes, TV stations usually have a lot of storage (usually between 250 TB - several PB), which is a very worthwhile investment. – Distraught_Proton Jul 21 '17 at 18:12
  • True, @RussellBorogove, but usually by that point, it's out of the TV station's hands, and into the hands of the distributor who makes that call and does that compression. From a TV station perspective, they usually aim for the best that they can provide. (Unless it's a local station using OTA, and you're getting free TV, then the station would be the one making that call). – Distraught_Proton Jul 21 '17 at 18:14
  • @JorenVaes, also, the compression done for TV isn't usually that bad. Obviously depending on the satellite or cable provider, the bit rates are normally kept high when exported from the station. But also keep in mind that all that data has to get crunched down and fired off into outer space, or shoved in a cable a sent across a long distance. It's all about efficiency. – Distraught_Proton Jul 21 '17 at 18:36
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These days, most all network TV stations receive media via satellite and either rebroadcast the programs live or record them for later use. Most stations use hard drive based media servers to store programs and movies and have software systems to manage playback for broadcast. Some content is sent to stations on hot-swappable hard drives. Resolution is generally 1080p or 4k.

Networks also sometimes send programming on discs (DVD or Blu-Ray).

Wikipedia Info.

Bottom line is, formats TV stations use aren't radically different from what consumers have access to. The media is just encoded at maximum quality.

I do animation and industrial videos for a living, but often do commercials for TV broadcast as well.

  • In your experience, is uncompressed or non-lossy compression ever used/submitted outside of production? (i.e. some analog to Redbook Audio) – Yorik Jul 21 '17 at 18:49
  • Uncompressed HD is about 50 GB/hour or more... – Thorbjørn Ravn Andersen Jul 21 '17 at 19:17
  • 50GB/hour is around €2 in consumer-grade HD, a fraction of even a cheap VCR-tape, so this isn't the limiting factor. – Lenne Jul 21 '17 at 22:35
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    Really, I only see raw, uncompressed video in editing. When feature length movies are sent out to digital theaters they will be around 400 to 500 GB in DCP format with almost no compression applied. That's as close to raw as I know of for any distributed media. Materials sent to TV stations home some compression, but high end codecs like Apple ProRes are so good that image quality holds up amazingly well once you start squeezing a little. – Scotty Parker Jul 22 '17 at 0:07
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    @ScottyParker: Especially in editing you'd expect to see (reasonably) compressed video formats. There's usually no reason to edit with uncompressed video, due to excessive bandwidth and storage requirements. Apart from that even most high end productions usually use some form of compression at the recording stage (usually at least some mild (lossy) wavelet compression, in many cases chroma subsampling and bit depth reduction as well). In editing in particular you might find heavier compression/downsampling when proxy files are used, since editorial doesn't need all that information. – Graumagier Sep 16 '17 at 14:09
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There are really two things that go on at a TV station, production and playout (With some crossover for things like live sports).

On the playout side a modern TV station looks very much like a datacentre and actually in some instances playout is even done from specialist bits of the usual cloud providers! Compressed audio and video (at a wide variety of bit rates) being carted around on IP networks, why not, you are going to be producing an MPEG transport stream at a few Mb/s or so at the statmux anyway.

Program distribution is generally file based, usually at a somewhat higher bit rate then the eventual transmission will be, but in most cases at a very much reduced rate compared to those used in production (Cost of bandwidth, particularly on satellite links).

For production, compressed video is NOT popular, because it will be processed extensively, 1.5Gb/s, 3Gb/s and 12Gb/s are the common rates over Serial Digital Video links.

IP based networks here are very much state of the art, at 10Gb/s(Often very slightly compressed (TECO) if running 4K), 25Gb/s, 40Gb/s and 100Gb/s links typically using leaf and spine networks using Cisco or Arista switching fabric, SMPTE 2022-6 is what most are using in the field at present, but SMPTE 2110 seems likely to take over once finally ratified.

Arena have the first 4K IP based production trucks 1, but it is clearly the way of the future.

  • I remember at IBC last year, there was a company that had 100Gb/s routers aimed at the content production/distribution market. They claimed that they had some kind of QoS special sauce making them better as the alcatel (now nokia) or cisco switches, although my computer-science background friends were skeptical about this. – Joren Vaes Jul 21 '17 at 20:27
  • There is Always someone at IBC claiming secret sauce! The elephant in the room with IP switches is that the IT industry does not really understand latency and jitter, it thinks in terms of average thruput, it took a lot of talking before the idea that buffering DOES NOT HELP sunk in (Also the fact that just because you can buffer does NOT mean you can take a port down for a ms every few minutes to do self tests!). – Dan Mills Jul 21 '17 at 20:38
  • Well, @JorenVaes, 100 Gb/s is a real thing. Not to mention that when talking about data transport, it's possible to go faster. I've worked with Fiber multiplexers that can do close to 8 Tb/s using CWDM. Now you obviously can't play any video at that speed, but in transport, it's all just bits. – Distraught_Proton Jul 21 '17 at 21:13
  • Well, bits and timing, and it is the timing that causes most of the pain in this stuff. There are a couple of Cisco and a couple of Arista networks switches that actually work with this, and some muttering about Juniper kit, but it is a long way from a situation where any old 10G/100G uplink switch will get it done (Especially for the seamless redundancy in 2022-7). – Dan Mills Jul 21 '17 at 21:53
  • I was not claiming it is not. We were sceptical about their hardware being significantly different form the common ISP hardware from cisco and nokia etc. – Joren Vaes Jul 21 '17 at 21:53
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For television the current format is ATSC (Advanced Television Standards Committee). The codec used is MPEG-2 (Motion Pictures Editing Group). It supports both 720p and 1080i. the i and p refer to the type scanning used in generating the image on the screen, i being interlaced scan and p being progressive scan. The audio portion of the signal supports 5.1 surround sound. ATSC supports both blu-ray and DVD for video with a wide range of aspect ratios and frame rates. However different systems are used in countries outside of North America. When transmitted both video and audio are combined using a process called multiplexing. In the receiver these signals are separated into their individual streams such as video,audio,subtitles, movie info etc by demultiplexing.

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