Convert at Low Bitrate or High Bitrate and Shrink

[doggyofone]

I have a 4 hour video that I want to rip to 1 DVD. The question is, do I rip at a low bitrate - ie: 2400, or rip to a higher bitrate ie: 5000 and shrink the larger mpg with DVD rebuilder?

[Baldrick]

what is the source file? avi,mpg? then encode to correct bitrate directly. You can also use a lower video frame size / resolution like 352x480

[doggyofone]

The file is an AVI. What will using a lower resolution do?

I've started an avs script in FreeEnc and changed it to this:

AVISource("Name.avi",false)
AVISource("Name.avi")
ResampleAudio(48000)
LanczosResize(352,480)
AssumeFPS(29.97, True)
ConvertToYv12()

Look OK?

[ZippyP.]

What will using a lower resolution do?

If the bitrate is low then a lower resolution will look better. The bitrate will need to encode fewer pixels preventing blockiness, the down side is a softer (less sharp) image.

If you're creating an mpeg from an avi then make it the correct size to begin with, use a bitrate calculator. (link) No sense wasting extra effort and losing quality in the process.

[doggyofone]

I've got bitrate calculator which gave me ~2700 kbits. I tried 352x480, which gave me a sqeeezed image - which I assume my DVD player will fix when played. The image did appear to have lots of blockiness, which the avi did not have. I think bitrate calculator gives a bitrate based on a 720x480 image. The resulting file was 2.7 gig, versus 4.5 if done on a 720x480 image. Should I increase bitrate to make a larger mpg?

[ZippyP.]

I've got bitrate calculator which gave me ~2700 kbits. I tried 352x480, which gave me a sqeeezed image - which I assume my DVD player will fix when played.

Or get better DVD playing software which will adjust the image properly.

The image did appear to have lots of blockiness, which the avi did not have.

What program did you use to convert?

I think bitrate calculator gives a bitrate based on a 720x480 image.

No, the calculator gives the bitrate based on running time and file size only.

The resulting file was 2.7 gig... Should I increase bitrate to make a larger mpg?

Depends on if you want to fill the disk with this video or if you want to put two on one disk.

[jman98]

What software are you using to encode? There is a world of difference. CCE and ProCoder are 2 of the very best, but they are very expensive unless you can find (cough! cough!) "demo" copies that don't expire. TMPGenc is pretty good and despite the trash talking some give it here, the newer versions have improved the quality of the MPEG-2 encoder over how it used to be.

Bit rate has nothing to do with resolution. It's just that with a lower resolution, as ZippyP said, your encoding bits will go over a smaller image, which will reduce blockiness at the expense of a less sharp picture.

It also can make a difference if you are doing VBR (Variable Bit Rate) or CBR (Constant Bit Rate) encoding. VBR is better at lower bit rates as you could set a range of, say, 3500 max. avg. 2700, min. 2000, and the encoder will use 3500 at more complex parts of the image and 2000 on less complex parts, or values in between that range depending on the complexity. CBR just uses the same old bit rate on everything.

You could encode at a high bit rate and shrink it if your encoder isn't very good, but shrinking does reduce the quality a bit. It's not reallly noticable on standard definition TVs, but I have a bad feeling that when I finally get an HD TV and watch a DVD I used DVD Shrink on that what was done to shrink it is going to be evident.

[doggyofone]

I used FreeEnc, 2 pass VBR, Incredible Template(?)
I'm using Media Player Classic to preview before authoring and burning.
I have lots of room, so wouldn't a higher bitrate provide better encoding and less blockiness?
I have the "cough" software, but decided to try something different - read FreeEnc was very good.

[ZippyP.]

I have lots of room, so wouldn't a higher bitrate provide better encoding and less blockiness?

Normally, yes.

[doggyofone]

Thanks Z, I'm running this now.

[manono]

Look OK?

No. Why do you have the AviSource line listed twice, one killing the audio and the other keeping it? I guess the 2nd one becomes the active one (don't know for sure), but it's still pretty sloppy.

Why do you have the AssumeFPS line? Either the video is already at 29.97fps and it's not needed, or the video is at 23.976fps and you're going to ruin it by speeding it up.

And you have ConvertToYV12() because FreeEnc requires it? I don't use FreeEnc, so I don't know. That would be a good reason to have the line. If it requires another colorspace, then you convert to something else.

The question is, do I rip at a low bitrate - ie: 2400, or rip to a higher bitrate ie: 5000 and shrink the larger mpg with DVD rebuilder?

You do it right the first time and skip DVD-RB entirely.

[doggyofone]

Manono, I'm not sure why its there twice - this was created by Film Machine. Nice program, but runs CCE very slowly with CCE Front.
I cleaned the script up and reran with CCE.
Lots of blocking with FreeEnc - tons (352x480 2 pass). Cleaned up very significantly with the same script and CCE - 2 pass to compare and left at 720x480. FreeEnc did a poor job, CCE excellent. I used DG pulldown afterwards, as the source was PAL and I wanted NTSC framerate. I demuxed my audio with Virtualdubmod and put it all together with DVDlab.

AVISource("Name.avi")
LanczosResize(720,480)
AssumeFPS(25, True)
ConvertToYv12()

Hope this makes sense. I believe CCE requires Yv12?

[manono]

Hi-

Hope this makes sense. I believe CCE requires Yv12?

No to both. If the source is PAL, then it should be 25fps already, and the AssumeFPS line isn't needed. It doesn't really hurt anything, maybe slows you down a tiny bit, but just isn't very elegant. And CCE requires YUY2 input. So you add:

ConvertToYUY2()

as the last line instead. If you demuxed the audio and handled it separately, then you no longer need it in the AVI, do you:

AVISource("Name.avi",false)

[doggyofone]

Thanks again. I followed DJ Runpy's guide, but some stuff wasn't explained. like demux. I notcied that with a conversion to 23.976 the mpg minutes were longer than left with 25 fps. I put together a DVD this way and the audio was way out of synch. This is why I wanted to leave as 25 fps and run DGpulldown afterwards.
This looks like the correct basic script, per your help:

AVISource("Input.avi",False)
LanczosResize(720,480)
ConvertToYUY2()

I created a script with FitCD and for the same file it reads lke this (I took out assume 23.976):

AVISource("Input AVI.avi")
ColorYUV(Levels="PC->TV")
LanczosResize(720,384,0,1,544,318)
AddBorders(0,48,0,48)
#Trim(0,299561).FadeOut(150)
ConvertToYUY2()

I don't understand it all, but I believe it will add top and bottom borders and make the final product less stretched.

Once in CCE I have to remove the check for DVD to change the frame rate and frame size to 720x480 from 576. CCE doesn't follow the script - at least from what I see. Am I missing something here?

[manono]

Oh, you never said what the original resolution of the AVI was, and I forgot to ask. My fault. Yes, FitCD is the way to go for getting the resize done right. The crop, resize, and addborders is fine for that one, as long as you realize you're encoding for 4:3. The rest of it looks fine. You don't really need this line:

#Trim(0,299561).FadeOut(150)

It's commented out (a "#" in front, meaning it's ignored).

I don't understand it all, but I believe it will add top and bottom borders and make the final product less stretched.

Exactly. While your AVI is 1:1, you're encoding for 4:3. The player will resize it correctly at playback so that it'll have the correct aspect ratio.

Once in CCE I have to remove the check for DVD to change the frame rate and frame size to 720x480 from 576. CCE doesn't follow the script - at least from what I see.

I didn't quite understand all that you said. But yes, uncheck the "For DVD" box at the top, and don't let CCE do any resizing at all. You already have it in the AviSynth script.

[doggyofone]

Thanks again. Here's the original NFO:
Codec: Xvid 1.0.2
Resolution: 544x320
Aspect Ratio: 1.70:1 Anamorphic widescreen (2.35:1)
Bitrate: 755 kbps
Frame Quality: 0.174 bits/pixel
FPS: 25.000 PAL

Even when I add in a line for assume 25fps, CCE does not accept it. The encoder setting screen shows an NTSC profile - 23.976, 720x480 and the minutes are wrong based on my extracted audio. I have to uncheck the DVD box and change to 25 fps. The Frame size changes to 720x480 once the box is unchecked. However, shouldn't the frame size change to 720x384 via the script?
This is confusing, as CCE doesn't seem to accept parts of the AVS script. They have to be changed manually.

Can you explain how the script determined that I encoded 4:3? I chose 16:9 based on the 1.70.1 DAR.

[manono]

Hi-

Still haven't got it yet, eh? OK, lets get you squared away.

Even when I add in a line for assume 25fps, CCE does not accept it.

I assume you don't literally have this:

AVISource("Input AVI.avi")

That's just a sort of shorthand for the full path, something like this:

AVISource("H:\Barsaat Ki Raat\Movie\Lagarith.avi")

Always test out your scripts in VDub(Mod) before sending them to CCE. VDubMod will give you a better error message that should help you pinpoint the problem.

I have to uncheck the DVD box and change to 25 fps.

Yeah, so? If it bothers you, set up a "PAL2NTSC" template that you load whenever you do one of these. It's loading its default template. You can even change the default, as I have done, to be whatever you like.

However, shouldn't the frame size change to 720x384 via the script?

No. You're giving it active video of 720x384, PLUS you're adding borders (black bars) on both top and bottom of 48 pixels (48 x 2 = 96). 384 + 96 = 480

Can you explain how the script determined that I encoded 4:3? I chose 16:9 based on the 1.70.1 DAR.

You did it in FitCD when you didn't check the "anamorphic" box, so by default it created a script for 4:3 encoding. If you go ahead and choose 16:9 in CCE, the resulting DVD will play with bad aspect ratio. If you want to encode for 16:9, check the anamorphic box in FitCD (in the "Destination" section) and use the changed script it gives you. Here's FulciLives' guide for using FitCD:

https://forum.videohelp.com/viewtopic.php?p=1487285#1487285

[doggyofone]

Manono, thanks a ton for the help.

I'm anxious to learn some basic scripting and you've answered my nagging questions. I've spent many hours on this and tossed a pile of encoded mpeg 2's trying to get this right. Looks like I've got some additional tossing to do, but now I'm on the right path.
6 hours with each 4 pass CCE encode, + authoring + burning. Faster to test CBR to check.

Back to the old drawing board.

[manono]

When learning and testing, maybe you'd want to test out just a section. Use the Trim command. Say you want to encode just 1000 frames between frames 2000 and 3000, then add this as the last line of the script:

Trim(1999,2999)

Or say you want to run a quick one pass VBR on it, so you can get your results more quickly. Change to One-pass VBR (OPV Mode) and let 'er rip. You'll lose control of file size, but again, the idea is to get some quick results to have a look at. And it's much better than CBR encoding.

[doggyofone]

Thanks again.
I finally understand the basic math end of this and FITCD is an excellent tool for creating the avs. I'm pretty sure I could work without it, or at least try and I will.
Appreciate all the help.