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  #21  
07-30-2012, 03:51 AM
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If you're mixing sources into a single video -- 23.976 and 29.97 -- then you'll need to retain IVTC (leave 24p/23.976p as 29.97i) and deinterlace it like you would the 29.97 footage, using Avisynth QTGMC method. That will ultimately be easiest for you, for the editing software, and will retain quality on the final export for Youtube.

There's really no good way to mix sources when in their native frame rates.

We need to get that Avisynth "kit" online soon, it seems. It'll save folks like yourself much of the initial learning curve headache.

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  #22  
07-30-2012, 06:43 AM
jmac698 jmac698 is offline
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Admin,
As I said I was looking for suggestions for this. However I thought another approach would be motion compensate to 30p. I've read a test of various web deinterlacing schemes and they all screw up, but they noted Amazon video was one of the better ones. So I'm taking into account the final destination here.

Also, deinterlacing telecined footage as you suggest would just (badly) recreate a 3:2 pattern in frames instead of fields. You could accomplish the same effect with IVTC to film then pulldown again in frames, except this time it would be the real frames instead of the guessed deinterlaced versions.

Last edited by jmac698; 07-30-2012 at 07:16 AM.
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  #23  
07-30-2012, 09:13 PM
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I mentioned different methods to change the frame rate from 24p to 30p.
Here's a pretty good example, using Avisynth, of two of the methods.
http://www.youtube.com/watch?v=_CSqZ...ture=endscreen
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  #24  
07-31-2012, 07:21 AM
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I've found out that YouTube accepts lossless formats and encodes to h.264. Also higher resolutions are streaming at a higher bitrate. So it would even be worthwhile to upscale some clips. Higher framerates also give better YouTube quality, so another reason to choose 30p as the destination.
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  #25  
07-31-2012, 05:29 PM
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You need to start cutting out selected scenes from all your videos. In order to do this with no quality loss whatsoever, you have to use a "cutter" program. These types of programs won't re-encode your scene selection. However, there is one slight disadantage; you only get a rough choice of where to cut (because of how video works).

I suggest you use http://www.videohelp.com/tools/Free-Video-Dub and start cutting out all your videos, but leave a few seconds room before and after the scene. Be sure to avoid installing all the toolbars!

I've tested MPEGStreamClip and while a nice program, I wasn't able to prove that it was a lossless "cutter" type program. I'm open to 2nd opinions, but for now I'm going by the program description of videodub as lossless (hope to qualify the program soon).

By the time you collect all your clips, I should have a package for you to take the final steps.

Last edited by jmac698; 07-31-2012 at 05:54 PM.
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  #26  
07-31-2012, 10:32 PM
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HI jmac,

I just took a look at the Video-Dub link. DVD's are mpeg-2's. Not sure that Video-Dub would work since it doesn't list that as one of the input formats that it would take? I don't think .mpg and mpeg-2 are the same thing?

Since mpeg-2's are necessarily used for DVD's, when you take the footage off a DVD you have to save it as something else. You can't save it in your hard drive still as mpeg-2, right? This was why I was using Mpeg streamclip to export the footage off my DVD's. Mpeg Streamclip came highly recommended for this purpose by several people.

feel free to correct me if I'm wrong.
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  #27  
07-31-2012, 10:48 PM
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I just tried Video-Dub to open one of the DVD vob's. it says it "processes" it, but nothing opens up or plays. Also tried inputting one of my other files I already have in my harddrive and it opens and plays fine. So, it doesn't seem Video-Dub will work in terms of getting footage off the DVD's

thanks.
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  #28  
08-01-2012, 02:00 AM
jmac698 jmac698 is offline
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DVD's store video as VOB files. VOB is a container. Inside this container are mpeg-2 files, plus subtitles and navigation (seeking) indexes. You can extract the mpeg-2 inside the VOB exactly. *.mpg is the usual name given to an mpeg file. It may be mpeg-1 or mpeg-2, and technically it's called a Program Stream, but usually you can simply assume it's an mpeg-2 file.

I had similar difficulties using *.mpg with FreeDub. StreamClip is perfectly good. That's my fault, as I wanted to verify it myself first; I checked the manual https://people.ok.ubc.ca/creative/MB...7s%20Guide.pdf and it's indeed GOP level.

In this case, save your files from DVD as MPG.
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  #29  
08-01-2012, 12:59 PM
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Hi Jmac,
thanks for further clarifying vob's. But when I tried opening one of the vob's from one of my DVD's in Video-Dub nothing came up on the screen, so therefore I wasn't able to use it to cut scenes out of the footage. It didn't seem like vob's were an input format that is accepted.


Quote:
Originally Posted by jmac698 View Post

In this case, save your files from DVD as MPG.
Do you mean save them as mpg when using Mpeg StreamClip? If that is what you mean, the only option there (in terms of mpg) is to save the footage as mpeg-4's, which is what I was already doing...which is when I came upon my original question for coming onto this forum. When saving it has a box where you can tell it how many fps, and I was confused about that because of the difference in pics/s and frames/s that gspot was indicating.

Or do you mean save as mpg when using video-dub to clip out scenes? Doesn't seem like I can do that since Video-Dub isn't opening/able to play a vob (it seems), as per what I stated above.

thanks!
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  #30  
08-01-2012, 01:40 PM
jmac698 jmac698 is offline
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I believe that we've both determined that VideoDub was not going to work for mpg files, even if it says so.

Others were correct in recommending StreamClip in the first place.

I have since received further confirmation that StreamClip does work correctly for cutting mpg files. By correctly, I mean that I was looking for lossless cutting, otherwise known as a GOP-level editor. The advantage of this type of cutting is that there is absolutely no quality loss.

Please see the guide below.

I will briefly mention what GOP means;
GOP - Group of Pictures. This is a set of video frames which are self contained. As an example, on an NTSC DVD, it's 12 frames or about half a second.

You need to realize that mpeg and other codecs will take a single picture in the video, and base the following frames off that picture. It does this by saving only the changes to the first picture.

For example, if you have a still scene of keys falling onto a table, mpeg will store the first frame with the table and keys being held, then it will store only the keys in each falling position for the next 12 frames. You can imagine that this results in a major savings in data, and is why mpeg is able to reduce the filesize of the original.

It also makes sense that this GOP should restart when you cut to a different scene, as the change will be so much that saving the differences would be inefficient. A good encoder will do this to improve quality.

Last edited by jmac698; 08-01-2012 at 02:21 PM.
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  #31  
08-01-2012, 02:17 PM
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I wrote this for newbies, skip the formalities and go to Opening Your File.

Guide to extract a clip from an MPG, VOB, or DVD with MPEG StreamClip

Testing Conditions
-The version of MPEG StreamClip used in this guide was Windows 1.2.1b5
-The procedure was tested with a vob and an mpg file

Conventions
-The symbol "->" is used to indicate a sequence of actions in a menu. For example, File->Open means to click the file menu, then click the Open submenu.
-The "*" symbol is being used as a placeholder for a name prefix. For example "*.vob" refers to any file, of which the filetype is VOB. This part of the filename is referred to an the Filename Extension. It may not display in Windows, but instead only the main filename is shown, with an icon. You must change your view settings to see the full name, or else realize how a certain filetype looks. Looking at the properties of a file should also show the real name.
-The "+" is used to show the simultaneous pressing of keys. For example, "ctrl+o" means to press and hold CTRL, then press O, then release both.

What is lossless cutting?
-MPEG and some other video formats are internally stored as groups of pictures, called GOPs. If you try to trim a scene from within a GOP boundary, the editor has to re-encode part of your clip. The re-encoding causes a loss in quality.
-There is a way to cut out a part of a video with perfect quality. It requires a program which supports lossless editing on GOP boundaries. StreamClip has this ability.
-GOP stands for Group of Pictures
-Video formats which are stored iin this way are known as inter-frame formats.

Opening an mpg or vob file
-If opening from a DVD, please see below.
-Use File->Open Files. Find a *.vob or *.mpg
-The file display in the main window, initially showing the first frame

Opening a DVD
---This section is untested---
-You can directly open the *.vob files as found under the folder VIDEO_TS. They will be named like "VTS_01_1.VOB". However, it's not obvious in which file your desired clip lies, therefore it is better to use Open->DVD.
-Try playing the DVD first and finding your scene with the normal menus. Then use the information display function of your DVD player to read the Title and Chapter that's currently playing.
-You can use this information to open the correct spot in StreamClip.

Trimming to Keyframes
-Move the slider under the video to the start of the scene you would like to keep. Note the position.
-Use Edit->Go to Keyframe, or use it's shortcut, by pressing ctrl+k. Note if the position moves ahead (further to the right) or left (previous to your cut). If the slider moved to the right, back it up. Try with ctrl+k again, until you've backed up far enough, that using ctrl+k goes to a point before your desired spot. This is called going to the keyframe. They could make this more convenient!
-Click the Edit->Select In, or use the shortcut I, by typing I.
-Use the same technique to move to a keyframe just beyond the end of your desired section.
-Click the Edit->Select Out, or use the shortcut O.

Saving Your Clip
-If you have opened a *.vob or DVD, do File->Convert to MPEG.
Note: There is a simple check to indicate that your clip is untouched. View your CPU Activity Graph and ensure that there's no spike in computing power used. The CPU will peak only if there's an encoding operation, which you are trying to avoid.
-If you have opened an *.mpg, you can use File->Save As.
-Name the file with a reminder of the scene it contains.

Congratulations! You have just made a perfect copy of your scene.

Cutting From Other Formats
-StreamClip supports cutting from other video formats, but it's ability to losslessly cut in these cases is unconfirmed.

Similar Programs
MPEG2CUT2 is another program which supports lossless cutting of mpeg files, known as a GOP-level editor.

Links
MPEG StreamClip
http://www.squared5.com/

MPEG2CUT2
http://rocketjet4.tripod.com/Mpg2Cut2.htm

Last edited by jmac698; 08-01-2012 at 02:49 PM.
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