Hot answers tagged

9

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 ...


8

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 ...


5

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 ...


4

It's a well known issue that red component in video devices suffers in presentation. The reason is the red color's long wave length and that our eyes respond more to long wave ranges (not to be confused with color sensitivity which would be in yellow-green range). For us to perceive the colors as equal (ref. responsiveness) the green and blue are ...


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

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 ...


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

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 ...


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

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 days burning the srts in with ffmpeg, and I was able to automatically rename the files and compress them for the various ...


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 ...


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

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 ...


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

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 ...


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. ...


1

I believe the answer is no, no, and no, for several reasons. First off, GoPro don't support their cameras as broadcast cameras. They are person video recording devices. I tried using the HDMI output of a Hero3+ camera to feed into a studio broadcast system, and when it didn't work the response was "it's not supposed to". The Hero3+ (and I presume the ...


1

Small sensor means two things: increased depth of field (everything is in focus, no soft backgrounds) and more noise in low-light conditions. If either of these are a deal-breaker then consider changing. Here's why maybe you shouldn't: To get a large sensor camera with the ease of use and ergonomics of this camera you'll be looking at cameras like the Sony ...


1

Your question was initially confusing because you had focused on "cables" which is not the correct way of looking at this. Once you've decoded a video signal to components, the closed captions are no longer available. If they were not inserted as open captions (aka subtitles) then they're simply not there. So any transport that removes the Line 21 caption ...


1

My guess, what you are seeing is most likely the result of the better color detection and processing with the sensor and image data and the better depth of field provided by a high quality professional lens. There is far, FAR more to image quality than simple resolution. The color accuracy of the sensor, the dynamic range, shadow detail, vibrancy and ...


1

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-...


1

What you are referring to is called hot linking, and while it may or may not technically be a violation of their copyright or terms of use (check their website for details) it is still generally considered a poor practice since you are effectively utilizing their bandwidth without mentioning that it is their bandwidth. Your best bet is to contact the ...


1

You may be referring to a "teaser" or "pre-cap". These are clips of upcoming shows designed to pique your interest and remind you of an upcoming episode. An ordinary teaser usually runs separately from the program, where (what we always called) pre-caps are teasers that run at or near the closing credits for an episode -- as in "Next time on XXX..." If ...


1

I am not aware of any particular term for showing the schedule. It's just a schedule of upcoming programs and may include playing teasers or previews, which are the video clips to promote upcoming shows. It could also be referred to as filler since it is content that is run while the credits are going (which they have to display) but want to fill it with ...


1

You could check out these links to see if they provide what you need: http://www.theneitherworld.com/mcpoodle/SCC_TOOLS/DOCS/SCC_TOOLS.HTML Caption Maker Pro: http://www.cpcweb.com/ And of course Scenarist and Encore, although both are DVD oriented you should be able to produce at least MPEG-2 with closed captions embedded: http://www.rovicorp.com/...


1

If you have at least 300-500kps of upload bandwith available you can push an rtmp stream of your live event to a CDN like youtube, dailymotion, livestream ... In terms of software I already used: Livestream, which provides among other things a tool called procaster with which you can broadcast your desktop, or a section of your desktop. You can even ...



Only top voted, non community-wiki answers of a minimum length are eligible