19

It's not an illusion - it's called chroma subsampling. Most video codecs do not represent colour in full resolution. This allows for more efficient "lossy" compression because it takes advantage of the fact that the human eye is more sensitive to brightness ("luma") than colour ("chroma"). Most lossy codecs lower the chroma resolution to half or one quarter ...


9

FFmpeg is probably being used more than you believe. I think the BBC uses it for some workflows, there is evidence that Laika and Weta may use it, and there is a fork called FFmbc which is targeted for professional broadcast usage. YouTube probably uses FFmpeg to decode as shown by some unique decoding issues (but this was several years ago that I read ...


8

FFmpeg's loudnorm filter can be used. Basic syntax is ffmpeg -i in.mp4 -c:v copy -af loudnorm=I=-23:LRA=1 -ar 48000 out.mp4 The loudness range (LRA) should be 2 x max deviation. Also see the ebur128 filter for measuring loudness.


7

I work as an assistant editor on feature films, and use ffmpeg all the time, primarily for two purposes: Transcoding files to be uploaded for producers to view on digital dailies systems (Dax, PIX, etc). I've written up shell scripts that accept property-of and recipient strings as command line input, along with target bitrate, and then generate the desired ...


5

Some Broadcasters require a Harding Test which is patented and proprietary, it creates a Certificate; thus getting someone to accept liability isn't going to be free. You can find a number of places online that will test a video file (or Game, Poster, Art, etc.) but those aren't free, the Harding website has authenticated tests and support. Free software ...


4

The main reason is support, usability and control. First, lets clarify that FFMPEG is an encoder, QuickTime Pro is a video utility that happens to include multiple encoders and Final Cut Pro is a non-linear editor and has nothing to do with encoders other than the fact it can output to an encoder (generally QuickTime I believe). For big budget commercial ...


4

I use it in my professional production chain all the time. Last week I was using it to batch through dozens of videos that needed subtitles burnt-in. It would have taken me weeks of tedious labour with Final Cut, it took me a couple of minutes burning the srts in with ffmpeg, and I was able to automatically rename the files and compress them for the various ...


4

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 ...


4

I wrote an ffmpeg filter which attempts to do this. It's not perfect, but it does seem to work well with a good part of the test samples I was working with. It has now been included into ffmpeg, and should be available in the next release. With mpv, you can enable it with: mpv video.mp4 --vf=photosensitivity The filter can be made more or less strict by ...


3

The obligatory ffmpeg answer (not a very good one, other answers still needed): You could feed your video through ffmpeg -vf drawtext=textfile=onscreen.txt:reload=1 With whatever other drawtext options you need to put your text where you want it, with the font you want. reload=1 makes it check the text file for changes every frame, but doesn't give you a ...


3

It varies a little from one server to another, but the basic components are an encoder/streaming client on the local client that takes input from the camera and turns it in to a stream that can be sent to the stream server on the VPS. The job of the stream server (such as Red5) is then to provide a publishing point that relays the stream to viewers. The ...


3

While pure red is tough to match, partly due to our visual sensitivity in that region, I've never noticed any tendency for red to 'pixelate' more than any other color. Maybe you're seeing an artifact of compression? Do you also see this in non-electronic displays like backlit signs, etc? Another answer here claims that manufacturers kept secrets about color ...


3

This was already done and seems to be done regularly in certain sports. Here is a (German, sorry) article from 1998 where this was done in the UEFA cup game Glasgow Rangers vs AC Parma. There where localized advertisements in Germany and Italy placed on areas originally pink. Here is the only English summary article on the subject that I found using a quick ...


3

What a great idea -- you should enter the marketing field! I don't know if anyone has thought to do localized advertisements yet, but image post-processing is routinely used, at least on American football broadcasts, to track the field and the marker lines thereupon, so as to provide various forms of in-game analysis. If they can do that, I'm sure they ...


3

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 ...


3

You can use an SDI Distribution Amplifier ("DA") (one SDI input, and two or more SDI outputs) for each camera so you can "duplicate" the camera video to send to both the production switcher and to your camera iso recorders. I use DAs I buy on Ebay. My current favorite is "AVUE 3G-SDI/HD-SDI/SDI 1 to 2 Repeater & distribution extender with re-clocking" ...


3

To legalize video with the Video Limiter: Set the Reduction Axis to Chroma and Luma. Set the Signal Minimum to 0% (=0 mV). Set the Signal Maximum to 103% (=700 mV + 3%). The rest of the settings may take some experimentation to find something that looks good for your project. I strongly recommend double checking you are within limits with a good gamut ...


3

The reason for mastering out to an uncompressed / minimally lossy format is so that you have a master copy, which you can then use to make other copies, without generation loss, or having to re-render. You don't have to use Animation. There, I've said it. While it's mathematically lossless, it's only 8-bit, so swings ± roundabouts. While I used to only ever ...


2

Can't help with freeware, but i can shed some light on the professional side of things. At urgent.fm we use Zenon because most commercial stations in Belgium use it, and our station is one of the starting places for people interested into getting into radio work professionally in our region. That way someone who was trained at our station feels right at ...


2

Not sure about Windows, but for Ubuntu, you could always check out Rivendell. http://www.rivendellaudio.org/


2

I think the issue you see here is actually because of bright pixels against a very dark background. Most lossy compression takes into account that we are far more perceptive to lightness differences than we are color differences. Depending on the codec used, and encoding options chosen, the blocks used for approximating the video can be fixed size, which ...


2

"I have computers, recorders, att u-verse and an am radio" Then there's nothing you can't accomplish! (-: Google shows plenty of examples. This was the first hit for "audio delay software free": http://www.fountainware.com/Products/AudioDelay/index.htm


2

I would suggest you research a bit further and then refine your question. To me it seems that there is a bit of confusion in terms of the software components needed for creating a livestream. First you need to have a software component that acquires a live video from some device. This video needs to be encoded. Once it is encoded it can be streamed by a ...


2

There's another free, more lightweight alternative to wowza and red5 - the nginx-rtmp-module, which frees you from messing around with java https://github.com/arut/nginx-rtmp-module/ and here's a guide to set it up with the free Open Broadcaster Software (which unfortunately is windows only) https://obsproject.com/forum/resources/how-to-set-up-your-own-...


2

Webcams live in the universe of being devices plugged into computers, and switchers live in the universe of standard video sources being plugged into them. These two universes only talk to each other via specialized interfaces (if at all). Happily, there exists software that gives you switcher-like functionality as a software package for your computer. ...


2

As per the Broadcast Engineer's Reference Book, p. 203 This correction will match DF time to real time to within approximately 2.6 frames per day; to eliminate the residual error the timecode generator can be reset each midnight. So, apparently nothing. As far as the "extra" frames, Charles Poynton says, If a timecode sequence is to be maintained ...


2

Depends on who you ask. Old traditional people who grew up back in the bad old analog days have the Safe Action Area and Safe Title Area embedded in their brains. But even as old analog TV receivers evolved, there was less and less danger of losing the periphery of the frame to overscan. With modern LCD, LED, plasma, whatever, TV screens, there is ZERO ...


2

There are three different things that get called "broadcast safe": Colors gamut: You don't need to apply an NTSC broadcast safe filter, but you do want to make sure that your colors are all within gamut for the format you are using. If you use out of gamut colors, most of the time nothing happens. However, you run the risk of some very odd, very hard to ...


2

In general loudness correction is a two step process. (There's a little more to it for full EBU R128 compliance, but I work exclusively in the US and this all that is required for A/85 / CALM Act compliance.) Measure the long term/infinite loudness of the asset. Shift the level of the asset by the difference between the measured loudness and the target. ...


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