DVD-->SVCD=Good, iMovie-->SVCD=Bad... what's going on?

[graffix jones]

I think the subject pretty much says it all... if I encode from a .vob file with mpeg2enc (through AfroPic or FFMpeg) I get fantastic results... not very much worse than the DVD source material.
On the other hand, even when I export my source material from iMovie as a DV stream on the highest quality setting it looks almost like a VCD, utter garbage in my book... there's artifacts all over the place, and it no longer looks like 'video'... it looks like a crappy encoding job.
I export the movies I make from iMovie at 640x480 in DV/DVCPRO mode, 29.97fps, 48KHz Audio.
Here's the settings I'm using in AfroPic:

Decoding/BC

Auto-Size: Custom (640x480)
Aspect Ratio: 4:3
Frame Rate: 29.97
Deinterlace Checked

Encoding

Stream Type: SVCD
Bitrate: 2500
Quantisation Reduction: 2
Motion Radius: 24
Interlace Mode: Progressive
Video Buffer: 230
Reduction Factor - 2x2:4 4x4:4
Verbosity: 1
Min GOP: 8
Max GOP: 16
High Quality Filter: Maintain

Everything else in the Audio/Mplex and Pre/Post Processing tabs is at the default, except I selected to save the shell to the desktop.

I tried playing with the Reduction factor setttings, but all they really did was make the encoding take longer... the video quality didn't visually improve much.

Any help I can get will be much appreciated...
The SVCD's I've made during testing play fine in my Pioneer DVD-changer, they just look like crappola (though not as bad as a Toast VCD thankfully).

[bilestyle]

your whole post is really inconsistent. You said when you make a svcd from vob it looks great... and when you play a svcd made from a dv file it looks bad? Is that what you are saying? cuz the whole thing isnt makin much sense to me.. afropic doesnt even supports .dv input. And you arent correct about the reduction factor at all, 1x1 does put out better quality, ALOT better than 4x4, if you do 4x4 the quality will suffer a lot more.

any quicktime movie files i have run through pic have come out great for me. i never did any dv cuz its not implemented to support dv at all yet. Also why are you using 640x480 for SVCD, thats not the standard at all. its supposed to be 480x480, i dont know if that would affect the quality at all, but maybe it could. You could try doin xsvcd and use a higher bitrate maybe, but im still perplexed as to exactly what you are doing, being as though afropic doesnt support dv format files.

well it technically COULD i just havent added the code for it to be possible-

[graffix jones]

Wow, thanks for such a quick reply....
I'll see if I can clarify a bit.

You said when you make a svcd from vob it looks great... and when you play a svcd made from a dv file it looks bad?

You are correct... some tests I did with a clip from Shrek came out wonderfully, but the Halloween video I took of the kids (in DV format) looks like crap... with the same settings in AfroPic (aside from Deinterlacing).

And you arent correct about the reduction factor at all, 1x1 does put out better quality, ALOT better than 4x4, if you do 4x4 the quality will suffer a lot more.

Well, you aren't reading this 'in context'... what I'm saying is that the Reduction Factor almost made no difference in the ending quality of my video... which is what I'm trying to figure out. When I had the settings set at 4x4:1 and 2x2:1 it took almost 18 hours to encode a 7:30 clip... which was reduced to 6 hours with it set at 4 on both... (this is on an iBook 500).

any quicktime movie files i have run through pic have come out great for me. i never did any dv cuz its not implemented to support dv at all yet. Also why are you using 640x480 for SVCD, thats not the standard at all. its supposed to be 480x480, i dont know if that would affect the quality at all, but maybe it could.

Well, when you use the 'Expert' export option in iMovie, it exports it as a .mov, even though it's in DV format (it doesn't have a .dv extension). I export at 640x480 because if I try to Deinterlace a 720x480 clip (the standard DV size), I get crazy wavy lines around everything from yuvscaler (I think) as it converts it to an actual 4:3 aspect.
As I also said earlier, 640x480 works fine... it actually fills the whole TV without black bars and my DVD-changer reads the disks fine as well... they just look like hell.
Can you recommend any other export settings I could try from iMovie?
Thanks again for your help... AfroPic is a great program... I recommend it to everybody wanting to make SVCDs... I just wish I could make it work better with my source video.

[unscarred]

Ahh I have felt your pain once before, and cringe to see my tragic story retold by another...

IMHO, DV is crap for source material, depending on the stream's source.
But in order for me to get B+ to A- SVCD's from IMovie I do the following -

Export to Full Quality. Your original DV file should always be the file encoded from, i.e. those clips in your IMovie media folder. Exporting just copys those clips, adds a header and joings them if more than 9 min. - 2 GB. I wouldn't trust scaling in IMovie, so let the MPEG2 encoder handle it. You don't want to add time and a loss of quality by adding an extra step.

Now with the .mov you have created, enable high quality and single field in the Video properties tab. This will "correct" DV's interlacing. I haven't seen a mpeg2 encoder that de-interlanced DV correctly without enabling this function. I thinks DV has bottom frame interlancing and I haven't seen any settings on any other encoder to handle that, except Cleaner.

I use Media Pipe. Using it's de-interlacer, scaler, and defining FIELD as interlaced source should do the trick. I will post my Media Pipe config if its not working for you.

[Cornucopia]

Why are you even deinterlacing?

Your orig DV file is interlaced.
IMovie supports interlacing.
The encoders support interlacing.
SVCD supports interlacing.
You're playing it via DVD settop through to an INTERLACED TV.

You'll spend less time skipping the deinterlace process and your stuff should retain its resolution better (no interpolation) and have better temporal resolution (for motion).

Also, the best source would be UNCOMPRESSED material, the next best would be 100% Losslessly Compressed material, then light Lossy Compressed, then heavily Lossy compressed.

DV is compressed only 5:1 while DVD is compressed 10-200:1, so a good DV clip should compress cleaner and more efficiently than a DVD clip. And I've never had bad encodes from DV sources-3 years running.

I think the prob has more to do with the settings of the export (agree about no resize for IMovie--keep it at the standard 720x480), and to a lesser extent, the encode software, but possibly IMovie doesn't do the right thing and DOES sometimes do a recompress on export. BAD!! And if the footage is contrasty or noisy there will be much difference in encoding compared to a HOLLYWOOD MOVIE lit and shot by pros.

Suggestion:
Export a 30 sec or 1 min clip in a variety of ways, putting a Text title on begin of each. Then do variations with encode parameters-naming hints the setting. Burn multiple track SVCD. See which looks best and stick with that combination. It's a little bit of a pain to set up, but once figured out, you're done until the next change of software. Oh yeah, write it down. And tell us-share the wealth.

Happy encoding,

Scott

[graffix jones]

Wow guys, thanks for all the great suggestions.
I should have some time to play around within the next couple of days so I'll try out some of the things you suggest.

Why are you even deinterlacing?

Well, when I tried it without deinterlacing, instead of wavy lines around every part of the video that was in motion, I got lines running through everything (like they had whiskers). I deinterlaced to avoid that problem (which was eliminated by doing that), but that could have been a by-product of the bottom-field interlace and the DV export mentioned by unscarred... I'm not really sure... I'll still have to play around a bit to find the right settings.
I know a bit about doing video editing... I'm just a novice when it comes to making SVCDs out of it.
Thanks again for the replies, and I'll post back when I know something further (though I'll still check back for more suggestions in the meantime).

[Cornucopia]

That kind of problem you mention does sound like wrong field dominance.

Note: just about ALL DV footage is Lower Field dominant--it's supposed to be that way in the specs.

Also: all of the better mpeg encoders should allow you to specify either interlaced or progressive, and if interlaced, chose which field.

Again, you can try the variety test.

Have fun,

Scott

[bilestyle]

in afropic in the decoding tab you can choose "change interlacing" and select bottom field first, and then it will feed it to mpeg2enc with lower field dominant, and in the encoding tab choose interlaced as the interlacing mode and that should solve your problem (should being the operative word because i never us DV source material)

[markpith]

Hi,
I had about the same problem making a VCD from an iMovie movie.
I really didn't like the Toast export extension.
So this what I do right now:
Export your finished movie back to your camera (ofcourse you'll need a DVin option at your camera for this) and import back into iMovie as one file.
You can choose this option in the preferences. Now you'll probably hate the next step... But drop the one .dv file (which is your whole movie) from your iMovie project into cleaner... (I know it's really slow but it supports .dv's).
Now encode it as SVCD or VCD. I get satisfying results when I burn as VCD and play it on my TV. If you want a SVCD you'll need cleaner 6 or cleaner with the MPEG extensions.
Hope this information gave you some help...

Mark

[graffix jones]

Well, I figured out the most irritating problem, the one with interlacing.
No matter what I did in the AfroPic settings, I couldn't get it to stop displaying visual anomalies with the interlaced video, and when I tried deinterlacing, I got wavy lines around everything in motion.
The workaround I discovered made a huge difference though, so I thought I'd share it.
I simply exported the finished movie from iMovie using the 'Quicktime Large:Full Quality' settings, then I opened the exported movie in Quicktime Player, and in the 'High Quality' section of the Movie info, I checked the 'High Quality' and 'Single Field' buttons. Voila!
I didn't need to use any of the 'deinterlace' or 'change interlacing' functions in AfroPic, and the video quality has gotten much better. Now I just have to figure out how to get even higher quality (it's still a bit blocky and I want to get rid of the black bars on top and bottom), but things are looking very promising... it's actually starting to look like an SVCD now
I'll post back again as I play some more with this.
Hope everybody had a happy holiday... thanks again for all your suggestions.

[graffix jones]

Okay...
I've had a little more time to play with encoding, and the process I use to get 'good' quality SVCD compliant disks is as follows:

1. Edit movie in iMovie (or Final Cut Pro if you're so inclined)
2. When finished editing, export movie to Quicktime (using the "Expert..." settings in iMovie) with these settings: 640x480 (or any other 4:3 ratio down to 480x360), 29.97FPS, DV/DVCPRO (for NTSC systems, or DV-PAL for others), 32KHz 16-bit Audio (or higher if your DV cam supports it). The reason I don't export at the full 720x480 size is that when I encode with mpeg2enc through AfroPic, it adds black bars on top and bottom and slightly squishes the source clip in the middle... at 640x480 everything looks as it should and the picture fills the screen.
3. When the export is finished (depending on your machine this could take a couple hours) open the movie in Quicktime Player, select "Show Movie Properties" from the menubar, select "Video Track" in the left pop-up and then select the "High Quality" flag from the right-hand pop-up. Now check both the "High Quality" and "Single Field" buttons. Save the movie and quit Quicktime Player.
4. Now convert the .mov file with AfroPic using the default SVCD settings in all the palettes except the "Encoding" palette, which should use default settings also except for the following which are changed: Change the Reduction Factor settings (2x2 and 4x4) to "3", turn on the "High Quality: Maintain" filter, and change the GOP settings to "18" on both. You also may need to change the "File is larger than 4GB" pop-up in the "Preprocessing" tab, if your file fits that description.

This process results in 'good' quality 480x360 SVCD mpegs (in my opinion).
I've pretty much gotten the artifacting and blockiness to disappear, but I do get a little bit of 'buzz' on busy backgrounds or in some low-light conditions. I'm not sure if I'm expecting too much from SVCDs, but it turns my DV material into something more resembling older 'Film Stock'. I realize that it's the Motion JPEG compression that is responsible, but I had hoped to retain more of the source material's 'video-ness'... if you know what I mean. Just like the thread title says, if I encode from a DVD clip I'm hard pressed to tell the difference between the source and the re-encoded rip... looks like I'll just have to experiment some more.
Anyway, on my iBook 500 I can encode 20 minutes of video in about 12 hours with these settings, which is a lot better than the 18 hours for a 7:30 test clip I was doing with everything set to 'High Quality'. The visual quality also stays right about the same, at least in my experience so far.
Overall I'm very satisfied with the results, but I'll do some more playing around and see if I can bump up the quality without hitting User-SVCD territory... I'd like my disks to play in most standard DVD players that support it.
Thanks again for your guys help... I'll report back after I do some more tests.
Oh, and bilestyle, thanks for a great application... AfroPic has it's quirks, but overall it rocks.

[havema-1]

> The reason I don't export at the full 720x480 size is that when I
> encode with mpeg2enc through AfroPic, it adds black bars on top and
> bottom and slightly squishes the source clip in the middle... at
> 640x480 everything looks as it should and the picture fills the
> screen.

But do you maintain the original aspect ratio?

To maintain it, you should AFAIK just scale (4:3) PAL/NTSC 720 x 576/640 to 480 x 576/640.

There is a nice page describing Digital Video Resolution and Aspect Ratio Conversions at:

<http://www.iki.fi/znark/video/conversion/>

> I do get a little bit of 'buzz' on busy backgrounds or in some
> low-light conditions

This was just recently discussed at mjpeg users mailing list and one of the mpeg2enc developers wrote:

> 3. The eye is most sensitive to quantisation in dark shades. The
> quality is actually the same throughout but you simply *notice* the
> quality problems in the dark scenes. One optimisation I want to add
> to mpeg2enc is to automatically reduce quantisation (if possible) in
> darker scenes.
>
> 4. SVCD is actually a very bit-rate limited format. 2500Kbps is
> actually pushing MPEG-2 pretty hard. However, many DVD players can
> happily play over-speed SVCD. Mine goes fine with 3800Kbps video (it
> can probably do more but that is the most I've bothered to try).
> This gives MPEG-2 much more headroom for difficult to encode scenes.
> The trick is to set a fairly high peak bitrate but a relatively
> conservative quality floor (-q). This means the bits only get used
> when the going gets tough for the encoder so overall compression stays
> high. For SVCDs I tend to use:
>
> -f 5 -q 6 -b 3300

But 2500 kb/s seems to be the top speed my Pioneer 444 will handle and using greater bitrates makes the XSVCD too short anyway.

p.s. SVCD on a Macintosh memo and cookbook is at:

<http://www.sjoki.uta.fi/~shmhav/SVCD_on_a_Macintosh.txt>

Comments and corrections to the memo are welcome. I haven't yet experimented with denoising pipes. My source material is from a D8 camcorder -- does it benefit from denoising when making SVCDs?

[bilestyle]

you have to turn on the denoiser for the deinterlace check box to work--- it is REALLY slow so i suggest fast mode denoising if your are only interested in removing interlacing artifacts. i just got the new 1.6.1 of yuvdenoise so hopefully its faster-- im testin it out with the new mpeg2enc right now so hopefully things will be sped up, but i find the deinterlacing in yuvdenoise is EXCELLENT, no need to use any of those iprograms.

[graffix jones]

havema-1,
Thanks mucho for those great links... the "SVCD on a Mac" tutorial is fantastic... I've really wanted to know what all the options available to mpeg2enc mean since I started making SVCDs, and that site answered all of my questions.
Also, thanks for info about the buzzing problem... I was trying to figure out a way to get rid of it, but it's nice to know that it's a 'feature' of mpeg2enc, and not just something wrong with the method I'm using.

bilestyle,
I appreciate how quickly you update AfroPic to take advantage of advances in the open-source world. Thanks for the info on the interlacing artifacts. I think what I was seeing as 'artifacts' are actually the scanlines of the interlaced video when played back through Quicktime Player... in other words they're 'normal' for interlaced video when played on a progressive-scan display (i.e. my iBook). I never got around to trying those clips in my TV, but my hunch is they wouldn't be noticeable. I still prefer progressive-scan encoding though, so I'll give your suggestion a try when I get a bit more time... at the moment I'm poring over the tutorial link havema-1 provided, which hopefully will help me on my quest for pristine SVCD mpegs.

Thanks again guys, I really appreciate the help and guidance.

[graffix jones]

Whoa Nellie!
I finally figured out what was going on with my mpeg encoding (thanks havema-1 for the info page) and what a difference a day makes! (Isn't that a slogan for some product?)
Anyway, my problem was that I was deinterlacing the video, which make it look like an older (circa 1970's) film stock... i.e. it looked like crap.
Anyway, after reading havema-1's tutorial page, I decided to create a test SVCD with both progressive and interlaced mpegs using a few of the different settings on his page.
All I can say now, is 'wow'... the interlaced mpegs I created look fantastic on TV. I was thinking that the scan lines (comb-like 'artifacts') I was seeing in Quicktime Player were a byproduct of a bad encoding process, but I discovered that interlaced mpegs just view that way on a progressive scan display. The mpegs I made looked just like (lower-quality) video, which I am very pleased with... it's what I've been trying to accomplish all along.
The only problem (if it can be considered a 'problem') was that I had to use MediaPipe to create the mpegs... I could never figure out how to get AfroPic to create the same settings that I was using through MediaPipe... even when I knew what those settings were.
Unfortunately, whenever I tried to send an interlaced Quicktime Movie through AfroPic, I'd get errors from ppmtoy4m saying that the source video wasn't interlaced, and the output mpeg would look all funky... even when I checked the 'Fast Denoise' and 'Change Interlacing - Bottom Field First' buttons. I also made sure to change to 'Interlaced' in the encoding tab, but that didn't make a difference either... it appears that AfroPic doesn't recognize that the High Quality flag has been set on the source video... or I'm just an idiot that can't figure it out.
Plus, MediaPipe scales the video to a 4:3 aspect that fills the screen, whereas AfroPic adds black bars to the top and bottom of the video if I don't first export it from iMovie at a 4:3 aspect (like 640x480)... another 2-3 hour process usually, depending on the size of the movie.
So, needless to say, I'm using MediaPipe for the time being until I can get AfroPic to do what I want it to... it's kind of a pain to do the demux/encode/remux of the audio by hand, but luckily the geek in me finds it fascinating. I've created MediaPipes for all the processes I need to use, so it's just a matter of double-clicking the mediapipe configuration file, selecting a source movie in the file browser and clicking 'launch cli'... a pretty simple process.
Overall, I'm very pleased with the results I've gotten... now I just need a faster Mac.
It takes about 20-30 minutes to encode 1 minute of video on this iBook, so needless to say it's a long process...
Thanks again for all the help... hopefully I can return the favor some day.

[smcnally]

Happy New Year, All -

And thanks from me, too, havema-1, for the 'SVCD on a Mac' page.

A good deal of the traffic that goes on in these forums seems more geared toward copying DVDs; it's great to find threads like this one.

Creation of relatively 'high-quality' (x)VCDs of 'home movies' and photo slide shows - sourced primarily from iPhoto and iMovie right now - is what I've been after with some success. Another goal is that the final product plays on the widest swath of DVD players - but, one step at a time ...

To Some kind of point: I've used MediaPipe, ffmpegX, the MMT, and other tools over the last few weeks and appreciate the level of control they give; I'm at least as comfortable with the CLI as I am with a GUI. I also appreciate the rate of change the underlying code goes through, but it does seem that 1) documentation, or better, the HOWTO, is not always completely up to current versions of the software and 2) that this should be a good thing w/r/t being an opportunity to address a need...

Documentation would be great; tutorials on toolsets are even better.

In the Apple Store here in NYC, e.g., the iMovie books were pretty literally flying off the shelf. While Apple would be happier selling more Macs with SuperDrives, truth is (x)VCD is a 'better' format for sending the latest kid & pet videos to Aunt Hilda in Ohio. And CD-RWs are everywhere already. I've gotten interest from publishers just from the notes I've taken re creating (x)VCDs with free (beer and/or speech) software; there's much more & better stuff out there, so how does it come together to create a How-To guide (or even a HOWTO) for (x)VCD on OS X?

[cjw2]

Read this on *some* reply on another forum, dunno who originally wrote it.

You can add -4 4 -2 4 to the mpeg2enc string in MediaPipe and it goes heaps faster. Since I always deinterlance to make encoding even faster I'm not quite sure what happens to the quality when you use this, but I've heard that it isn't big (I haven't tried interlanced -4 4 -2 4, only interlanced by itself and progressive -4 4 -2 4, since I'm very impatient ) so yeah, do a test.