NTSC frames

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susanalic
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NTSC frames

Post by susanalic » Sun Apr 27, 2008 6:22 pm

HI, thanks for this tool

I don't understand why "NTSC frames", in selection, are 29 fps, when it should be 23.976 and/or 29.97 fps. My suggestion is to include those fps, thanks. At the moment, I have to translate NTSC frames to time.

steve
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Re: NTSC frames

Post by steve » Sun Apr 27, 2008 8:13 pm

In Audacity 1.3.4, NTSC frames are close to 29.97 fps as they should be.
You are probably looking at drop frames, or non-drop frames.
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susanalic
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Re: NTSC frames

Post by susanalic » Mon Apr 28, 2008 5:58 pm

Thank you steve

I know what drop and nop drop frames are.

Image

37:46.827 = 2266.827 seconds
NTSC frames (Audacity) = 65737

fps = 65737 / 2266.827 = 29.0 (and thats wrong)



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I'd prefer 23.976, since to sincronize I previosly remove the pulldown from video

steve
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Re: NTSC frames

Post by steve » Tue Apr 29, 2008 1:28 am

susanalic wrote:37:46.827 = 2266.827 seconds
Your pictures show 37:46.848 (2266.848 seconds), and 65738 frames, not 37:46.827 (2266.827) seconds and 65737 NTSC frames, but that still works out wrong.

When I run your test I get: 37:46.848 = 2266.848 = 67937 NTSC frames which looks about right to me.

I'm using Audacity 1.3.4 on Linux - you've not said what version or platform you are using, but I do notice that you have "Snap to" (Ajuste a) selected, which will move your selection a little each time you change the time format - that could account for the small differences between your quoted figures and the pictures, but it doesn't account for 29 fps instead of 29.97 fps.
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susanalic
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Re: NTSC frames

Post by susanalic » Tue Apr 29, 2008 4:20 am

Audacity ® 1.3.4-beta (Unicode), the lastest I think

Win xp sp2

___
PAL 25 works fine

steve
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Re: NTSC frames

Post by steve » Tue Apr 29, 2008 4:35 am

OK, I've tried it with Audacity 3.1.4 beta (Unicode) on Win XP Pro SP2

Again I get 37:46.848 = 2266.848 seconds = 67937 NTSC frame

Is this problem repeatable? If you generate a tone exactly 16 minutes and 40 seconds duration, what length does Audacity report in NTSC frames? (At the moment I've no idea what is causing the problem for you, I'm just curious about it).
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susanalic
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Re: NTSC frames

Post by susanalic » Tue Apr 29, 2008 5:40 am

Image

29000 frames

very strange

Edit: :idea:

I don't know why, but I've changed the language from Spanish to English and:

Image

29970 frames

stranger, how is possible this ?

:idea: And, if a language pack can change the fps, is it possible somehow to have 23976 ¿?

Edit_2: 29970 only with English; any other language, 29000

steve
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Re: NTSC frames

Post by steve » Tue Apr 29, 2008 4:43 pm

Very curious indeed. I've just tried it in English, French and Spanish, and they all work correctly (29.97 fps).

Perhaps you have some corruption somewhere, or running the Windows 98/ME version on XP? I've really no idea. The only suggestion I can think of is to download a fresh copy from http://audacityteam.org/download/beta_windows and completely remove your existing version (including the config file which I think needs to be removed manually), then install the fresh version.
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susanalic
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Re: NTSC frames

Post by susanalic » Tue Apr 29, 2008 6:32 pm

No lucky. I've remove appdata and registry entries.

No, win xp alone.

I've also download the standalone version, w/o installer, the same.

29000 is an exact number, corruption is unlikely

steve
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Re: NTSC frames

Post by steve » Tue Apr 29, 2008 7:12 pm

susanalic wrote:I've remove appdata and registry entries.
In Audacity 1.3.4, the settings are held in a configuration file rather than the registry (this includes language settings).
Documents and Settingsuser nameApplication DataAudacityaudacity.cfg
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