Time Code

[robinsj]

Is there anyway possible to set the timecode to 23.976 frames in stead of only 24fps. Problem I am running into is when you are editing a audio file that is almost two hours long, when I set it at 24fps the frames that I am editing in audacity are quite a ways off from the frames I am editing in a video editor, which uses 23.976 frames.... Just wondering, right now I have to do all the calculations with a seperate calculator..

[whomper]

not sure
but wouldthe ntsc dropframe give the rate you need ?

pick it from the timecode at the bottom of the screen

historical note
...we use " 24fps " for NTSC film and 30fps for NTSC video. This is because it's simpler and takes less time to write. However, it's not really precise.

Back in the day, NTSC TV video was indeed 30fps. However, video hasn't "really" been 30fps since color TV broadcasts started. Before them it was 30000 frames for every 1000 seconds. But to accommodate the extra color information, the rate was very slightly dropped by stretching the frames to cover an extra second for every 1000 seconds, making it 30000/1001.

30fps == 30000/1001 == 29.97fps

23.976p

Many 24p productions, especially those that are made only for TV and video distribution, actually have a frame rate of 24 * 29.97 / 30 frame/s, or 23.976frame/s (24/1.001 to be exact). Many use the term "24p" as a shorthand for this frame rate, since "23.976" does not roll off the tongue as easily. This is because the "30frame/s" framerate of NTSC is actually 30/100.1%, also referred to as 29.97frame/s – this framerate is matched when video at 23.976frame/s has a 3:2 pulldown applied. Similarly, 60i is shorthand for 60/100.1% fields per second.

Film productions may be shot at exactly 24.000 frame/s. This can be a source of confusion and technical difficulties if material is treated as normal video, since the slightly differing framerates can be problematic for video and audio sync. However, this is not a problem if the video material is merely treated as a carrier for material which is known by the editing system to be "true" 24frame/s, and audio is recorded separately from moving images, as is normal film practice.

24fps == 24000/1001 == 23.976fps

[whomper]

...frames I am editing in a video editor, which uses 23.976 frames.... Just wondering, right now I have to do all the calculations with a seperate calculator..

or set the video editor to 24 ?

looks like a feature request for audacity
provide real 24.000 rate
as well as a "24" rate that is 23.976

[robinsj]

Well I have tried the Film Frames 24P selection, but once you get about an hour into the audio file you get about 80 frames off from what the frames show in the video editor. If I understand you right, there is a feature request in already for true 24p (23.976)

[whomper]

no
i suggested it as a feature
you may want to make it more official and blatant by posting it on the features subforum

[kozikowski]

If you edit your video in Drop Frame, 23.976, then frame time in the editor and time of day should match. Specific time labels (not video frames) are dropped to make up the difference. You should also Audacity edit in 48000 rather than 44100. All your preferences should be video standard, 48000, 16-bit, Stereo.

I swear I saw a setting like this that allowed for the difference..... I'll look again.

You can get into serious trouble if you shot with a "24-frame camera" which is really running at 23.976 which most seem to be, and editing at 24.00. We regularly have this problem as does any house that has one foot in feature film 24.00 and the other in television commercials 23.976. Sometimes in the same machine.

Sometimes we cheat and make extensive use of the fact that if you don't go over a minute, nobody an tell you picked the wrong one.

Koz

[kozikowski]

I see it. No, there's no provision for 23.976. It may not be hard to add. It's a fixed cousin to NTSC Drop Frame. 3/5 or something like that.

It still bothers me you can generate a 2 hour audio show and it doesn't match a 2 hour long video show. Are you editing 24.00 feature film? I can't figure out where the difference is.

Koz

[kozikowski]

OK. I see it. If you're in 23.976 drop frame in your video editor and you take two time cues and subtract them, it doesn't take into account the missing numbers. In drop frame, subtracting 200 frames from 300 frames doesn't always give you 100 frames.

If you're editing frame accurate cues, that's rough.

Koz

[robinsj]

Yes, I am editing a 2 hour film, some of the changes i am making are about 55 minutes in, took me a little bit to realize it, but if I had audacity set at 24 frames, then when I went to edit the video the frams were about 80 frames off, so what I have been doing is just setting it to show hh:mm:ss.hundreths, and then i just take and figure out the total seconds, including the hundreths, and times by 23.976, and walla, I have the exact frame.

On a side note, I had been using audacity to open DTS files also, for quite awhile, and many different ones. All of a sudden, I didn't make any changes at all, but I can't open them anymore. Audacity crashs the moment I open it. Any ideas?

[kozikowski]

<<<I have the exact frame.>>>

That's what I was going to suggest. Time Of Day in the video editor is real and common between the two editors. I do have a calculator that talks directly in all the world's time systems. That's been handy.

http://www.calculatorsource.com/ci-9226.html

I've place a feature request for 23.976 DF.

Koz