My Divx -> SVCD conversion guide (Adv.TMPGEnc, MP3)

[puntloos]

Puntloos AVI -> SVCD conversion guide
For the impatient:
23,976fps, AC3, 16:9 AVI -> NTSC SVCD (optionally with mp3 audio)

TMPGenc settings in a nutshell:
(I will explain a lot of TMPGEnc settings below. I don't consider myself an expert, but I do believe I know what I'm talking about in practical situations, so I humbly suggest you read the bottom of the doc as well)

VFAPI Plugin: Make the priority of the Directshow Multimedia File reader highest so it will use (installed, right?) AC3/Ogg/Mp3/xvid/divx codecs.
Audio engine: (optional)If you dare: MPEG1 Audio Layer III encoder: (download and) select Lame.exe or TooLame.exe

Encoding settings:
video: 24fps (internally 30fps), NTSC, 3:2 pulldown
advanced: non-interlaced, Field B, 1:1 AR, Fullscreen, IVTC (Convert to 24 fps)
audio: (optional): MPEG-1 Audio Layer III, 128kbit or so.

Extra:
On my player, Pioneer 444, image gets completely distorted if you don't do the following weird trick. It has to do with mixing mp3 into the stream since it'll just work with mp2. This probably is a hardware bug, so might not work and/or be necessary with your hardware. You can also opt to forget about mp3 audio

1/ Create a NTSC-sized blank VCD file(yes, MPEG-1, MPEG-1, Layer2 Audio) of about 3 seconds. This shouldn't be too hard.
2/ Create a blank SuperVCD file (MPEG-2, MPEG-1, Layer2 Audio) with the same size as your final file, 3 seconds again. This shouldn't be too hard either.
3/ When recording (I use Nero 5.5) make the VCD track 2 (track 1 is the 'data' section), the SVCD track 3 and your final movie track 4.

The long story
OK I've been doing some trial-and-error with converting divx/xvid to svcd since I could never get it right. Always stuttering or other weird effects. For the record I have a Pioneer 444 player, perhaps it has something to do with its hardware-specific properties, but if you have similar problems with your player Im sure it's worth a shot. And even if you have no real problems I believe there are a few useful considerations in my little essay.

Since the TMPGenc settings I found to be working seem to pretty much disagree with everything I've found in forums etc (even when it sounded logical) I'll share them here.

Essentially I wanted to convert an AC3, 23,976fps (progressive of course) 16:9, 608x256 movie to svcd.

First a few preferences
TMPGenc doesn't know what AC3 is, I suspect it might also have problems with Xvid, Im not sure if it's related. One thing's for sure, before you do anything go to

Option -> Environmental Setting -> VFAPI Plugin tab

And make sure the priority of the Directshow Multimedia File Reader is highest. (Right click on it, and select higher priority a few times). Once that is done it will pretty much read any divx that you can also play normally on your system.

Optionally, if you plan to use MP3 Audio (this will probably work if your DVD player supports MP3 since it will use the same hardware to decode the audio anyway) you need to tell it where it can find the latest version of Lame.exe in the Audio engine tab. (download this seperately of course, duh). Lame is obviously the best mp3 encoder out there. Especially since we're really hurtin'
for every last byte I find 128kbit mp3 audio quite acceptable compared to the 256kbit mp2 audio. Especially since TMPGEnc's mp2 encoder doesn't produce the best possible mp2 anyway.

Inverse Telecine - also named 3:2 Pulldown
Now there are zillions of docs about inverse telecine, 3:2 pulldown etc and they do make sense. Of course you want to just store the 23.976 frames per second and let the DVD player hardware to do the rest of the work. Recoding and storing 29.97 frames per second would also work (and perhaps this what Im doing without knowing it, but I dont think so) but storing 6 frames more than necessary is wasteful. Less wasteful than some people claim by the way, the extra frames aren't totally lost since there would be fewer differences between the individual frames, which is easier to encode.

Now of course TMPGenc (Im using 2.59 btw) is made by some asian company so its engrish is probably losing something, but the bottomline is that the setting that would make the most sense would be:

Frame rate: 23.976 (internally 29.97 fps)
Video format: NTSC
Encode mode: 3:2 pulldown when playback

(I would assume they mean that the internal framerate is 23.976 and the mpg contains a flag that tells the player to IVTC to 29.97fps (which is NTSC). Also, you might first have to select the Encode mode before the right frame rate setting becomes selectable)

Sadly this doesn't work. At least not on my player. Still stuttering.

Now after trying pretty much all combinations I stumbled onto the settings that -do- work. Here they are. The bold lines are necessary for fluid playback, the other settings can be changed, these are what I'm using.

Stream Type:	MPEG-2 Video
Size:		720x480 Display
Aspect Ratio:	16:9
Frame Rate:	24 fps (internally 30fps)
Profile&Level:	MP@ML
Video format:	NTSC
Encode mode:	3:2 pulldown when playback
YUV format:	4:2:0
DC component:	10 bits
Motion s. prc.:	Normal

Advanced
Video source:	Non-interlace(progressive)
Field order:	Bottom field first (field B)
Source aspect:	1:1 (VGA)
Video arrange:	Full screen (keep aspect)
Inverse TC:	24 fps (non-interlace source)

Audio
Stream Type:	MPEG-1 Audio Layer III
Bitrate:	128 kbits/sec

System
Stream Type:	MPEG-2 Super VideoCD (VBR)

And burn

With Nero, all you need to do is disable standards compliance since we're creating nonstandard stuff here. Also make it encode to NTSC. I hope your player handles this, if not you're screwed.

Lastly I will Copy and Paste my only note I mentioned above:

On my player, Pioneer 444, image gets completely distorted if you don't do the following weird trick. It has to do with mixing mp3 into the stream since it all works fine with mp2 audio. This probably is a hardware bug, so might not work and/or be necessary with your hardware.

1/ Create a NTSC-sized blank VCD file(yes, MPEG-1, MPEG-1, Layer2 Audio) of about 3 seconds. This shouldn't be too hard.
2/ Create a blank SuperVCD file (MPEG-2, MPEG-1, Layer2 Audio) with the same size as your final file, 3 seconds again. This shouldn't be too hard either.
3/ When recording (I use Nero 5.5) make the VCD track 2 (track 1 is the 'data' section), the SVCD track 3 and your final movie track 4.

Comments on TMPGenc settings
- My player refuses to play weirdly-sized mpegs, so you need to convert to standard size. Now SuperVCD-NTSC actually is 480x480 but I found that my player accepts 720x480. So experiment. If your player seems to accept weirdly-sized MPEG's then by all means keep the output dimensions the same as the source, since you will lose quality (image sharpness) in resizing.
- Aspect ratio 16x9 will result in a fairly good compromise on a 4x3 TV. Yes, the sides of your image will be cut off, but if you don't you will leave precious little image lines for your actual picture. If you wish you can tinker with input and output ratio's to fill your screen and letterbox it more. Basically I believe I'm manually 'Pan and Scanning' but Im not up to speed with the lingo.
- The framerate 24fps works on my player, 23.976 doesn't somehow. Don't ask me why. Your mileage may vary. You definately want to encode at 23.976 or 24 and make the (tmpg engrish lingo) internal framerate 29.97 or 30.
- For bitrate and CBR/VBR I guess it's all up to you. Seasoned SVCD encoders have told me that TMPGEnc's Constant Quality mode is the best mode (even superior to Cinemacrafts MPEG Encoder which some people blindly seem to accept as the best encoder), but to make a neat fit you might have to trial-and-error entire encodes which takes a long time. CBR is for lazy and impatient people. VBR 2 pass is for patient people. (This is only available in TMPGenc plus, which is not free.). My encoder friend tells me that VBR gets you an inferior result compared to a perfectly tuned CQ, but my common sense kinda doubts the statement. I guess I'll try and compare a bit later.
- 10bit DC Component Precision is the only viable option. Encoding times only differ marginally if you set it to 8bits (1% or so) and quality is superior at 10.
- Motion search precision.. well, I did some tests.. 1000 frames at the lowest setting took 2:05 mins on my system (Celeron 900). Normal setting took 2:30 and highest setting took 8:15. Now the difference between lowest and normal is quite clear, so it's definately worth the 20% extra encoding time. I could -not- tell the difference between Normal and Highest setting. I'm sure there is some, and I only briefly compared one 1000 frame section, but for anything but 'archive quality' stuff I wouldn't bother setting it to highest.
- Noise Reduction, Ghost reduction, Sharpen Edge.. Well, only if your source is 'home made' or 'recorded off TV'. Experiment I guess, but these filters don't do much with 'perfect' sources. (no, divx isn't perfect, however the compression artefacts you get by using low bitrate divx as source won't be improved by this.)
- I don't know anything about GOP structures or Quantize Matrices. If anyone wants to add to this (esp. if you can achieve considerable improvements in final quality) let me know.
- Outputting YUV data as Basic YCbCr not CCIR601 is preferrable, if your DVD player can handle it. Most players can. The rationale is that for every color CCIR allows 227 values while Basic YCbCr allows 256 values. Essentially this allows for more individual colors to be displayed. This is good if your source is true RGB (like all divx avi's are). DV is CCIR601 so if your source is DV, remapping 227 values onto 256 values will cause a loss in definition i.e. bad.
- Softening Block Noise is a good thing though it will make you lose a little sharpness. For movies with lots of action scenes I would advise this since you will get blockiness. If a movie is slower you can probably better either not engage this filter, or do this and enable the sharpen filter at the same time.
- As I mentioned before, if your DVD player can handle MP3 it should also be able to handle mp3 inside SVCD. Usually the hardware/software used for decoding is the same so it probably won't even blink if you feed it mp3. You will need to point TMPGenc to your previously downloaded Lame.exe binary.

Well, that's about it for me. Happy Encoding.

[puntloos]

Ack, I didn't notice that there's a Guides forum.

I'll crosspost there (admins, feel free to delete this one since I can't do it)