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Understanding DVD Compression?
canyon289 asks: "My friends and I created a full length movie using a regular Sony Camcorder. After importing and editing all of the video and audio in Adobe Premiere, the exported AVI comes out to 19 gigs. The length of the movie is 90 minutes. We tried compressing it with Nero Burning Rom to a 4.7 single layer DVD but when played in a standard DVD player theres pixelation and frame skips aplenty. Does anyone know how to fit the movie into a DVD (preferably 4.7) and still maintain adequate quality?"
Try to burn it slower, if you noticed will run smoothly in your PC's dvd player but not in home dvd-player.
The full version is pathetically slow and not very good; the bundled versions are pathetically slow, not very good, and force you to use LPCM audio. ffmpeg + mplex + dvdauthor will do nicely. And there are tools that will wrap them all together for you in some sort of graphical thing, I think :)
CCE is the standard used in the rampant legal archiving of DVDs. Best DVD encodes I've seen of any of the major products. Nero has a quick and dirty encoder that is fitting 1hr-1:30 on a DVD5 with decent quality, but CCE sets the standard.
MPEG only specifies the decoder not the encoder. So
1. Choose a quality encoder
2. Use a high quality mode (if it has one) usually this enables more MV searches
3. Use multiple passes if supported. This helps distribute the bandwidth where it is needed more.
Mencoder [part of mplayer] can encode DVDs using lavc that look [for the most part] just as good as the original on a CD. It'd be trivial to get near losslessness in the size of a DVD.
Tom
Someday, I'll have a real sig.
http://www.doom9.net/
You want a multi-pass, high quality encoder to create your output files. For video and on Windows, I suggest Tsunami Mpeg Encoder (TMPGEnc). It's been a few years since I've messed with any of this, but it was quite good and inexpensive 3-4 years ago. It does 2-pass encoding and can output any number of DVD-compatible formats.
If you're still having problems, you might try reducing the resolution. DVD supports 704(720) or 352 vertical lines. Obviously quality suffers as you reduce resolution, but if you're having problems squeezing your content onto a DVD at 720 lines, you may just get an overall increase in quality this way.
Also, you don't talk much about your audio. Is it raw audio (which is really big and uses up lots of room on the disc that could be devoted to video)? You may have good results compressing this, as well.
I like http://www.doom9.net/ for all things video/dvd/vcd. They have a number of guides which detail the various methods of compression and burning. It's pretty likely that you'll find the tips you need there.
ffmpeg -i INPUT.avi -target ntsc-dvd 01.mpg /dev/dvd -dvd-video dvd
mkdir dvd
dvdauthor -o dvd -t -v 4:3 01.mpg
dvdauthor -o dvd -T
growisofs -Z
rm -r dvd 01.mpg
Basically, you need to author your DVD. Authoring takes the AVI file output of Premiere, compresses the video to MPEG2, the audio to AC3, creates menus (if you want them) and prepares and burns the entire thing. Good authoring software does a MUCH better job at compression than the crappy encoder in Nero, since these programs are designed to create only video DVDs, whereas Nero is designed to do everything (and none of it particularly well). As you're already using Adobe products, you may want to try Encore. It's their DVD authoring application. However, if you're open to other options, I highly recommend Sony DVD Architect. Both of those programs will create splendid quality results; the difference is that Adobe's Encore will give you more options (but is harder/more confusing for beginners) while Sony's DVD Architect will be much easier to learn and use (however lacks some of the fancy features that Encore provides).
You entered the wrong url in your browser. Instead of slashdot.org try videohelp.com.
Dan East
Better known as 318230.
Hey guys. No of course its not a rip if you guys are wondering. What kind of rip would be twice the size of the commercial dvd? Please don't think youre supporting piracy by giving me suggestions. I'd really appreciate any help I can get and thank you to whoever has already given me more possible solutions. I'll also bring you up to date on what I've done. The nero compression barfs during the credit and theres pixelation everywhere. However the audio and picture stay in sync. I've also tried Winavi but there are parts where the dvd player can't play the sound or video. Does anyone know if FFmpeg or some apple program will work? It doesn't matter what operating system. Thank you
Oh yes. Im very sorry that I forgot to mention the details. Here they are. Pixels: 720 x 480 Duration: 1:30:32 Audio Bitrate: 1536 Kbps Audio Sample Size: 16 bit Audio Format: PCM Framerate: 29 frames a second (can't lower this anymore, The movie gets too choppy) Video Sample Size: 24 bit
Simple, free, one-click solution: DivxtoDVD. Fast and easy, quite good results.
If you want to get into it more, you need Avisynth (to load the AVI, scale it, apply filters); a video encoder (I like HCenc), an audio encoder (like BeSweet), an authoring app (like GUifor DVDAuthor, finally a burning app (use Nero or whatever came with your burner).
These are all free Windows software, you can do it all in Linux, but it's not so user-friendly. Most Mac users tend to use commercial software.
There is a fixed limit on the max bit rate, some older DVD players don't have the horsepower to decode and play high bitrate files. You can lay down high bitrate files just fine, but the player might not be able to play them. This is especially problematic for PCM files, you really should encode them as AC3, which are far lower bitrates but are essentially the same quality. There is a fixed limit on the total (audio + video) bitrate in the DVD spec, don't exceed it or you end up with stuttering files just as you described.
90 minutes on a single-layer DVD should look excellent. You will use a bitrate of about 6 Mbps, which is plenty for high quality SD. But you must use a decent encoder.
Nero's, as well as those on most all-in-one DVD edit/encode/author software are crap. The one that comes with Premiere is actually very good, but I prefer CinemaCraft Encoder Basic available at Visible Light for a mere $58. (Understand that the full version retails for over $2500 and has been used on commercial DVDs for many years.) It's not only quite good, but it's very fast. And it will plug directly into Premiere so you don't have to save that 19 GB intermediate AVI (or go through the associated additional encode/decode cycle, which also degrades the quality).
After encoding, you must author your DVD. Adobe's Encore is good, but at $350, it's pretty expensive. I recommend DVD-Lab, the standard version of which is only $99.
Both of these are available for trial download, so you don't have to take my word for it.
Note that for audio, you can use MP2 for PAL destinations, even for commercial DVDs, and CCEB will do this for you. But for NTSC destinations, MP2 is not required to be supported by the players. You'll need to obtain a DolbyDigital (AC3) encoder, which is a different story (or you can use PCM, but this would force you to use a lower bitrate on the video, which would degrade the quality, so I don't recommend it).
Xesdeeni
There are 3 simple rules not to lose quality:
7 .html ). If the program allows it, select also "progressive scanning" option. Near all TVs,DVD players support it. It becomes dubbed as "480p"
1) Perform effects, fade in,fade out etc on non compressed source never overwriting it. E.g. use "edited.avi" as output file
2) Never upsample. E.g. don't convert to DivX, it is lossy, "final" format. Decide what media you will need and compress using regular TV specs, don't delete the source if you can. For example, if you want to output to NTSC/Progressive (which in case, camera is not HD), here is resolution specs. Anything lower loses quality, higher won't work.
648 x 486-->Standard NTSC ( http://www.strata.com/support/3dmanual/ch13/ch13_
3) Do not transcode. E.g. do not convert something to DivX (mpeg 4 variant) and re-convert it to Mpeg 2..
4) Always use "multi pass" encoding. Not only the result will be smaller, it will be better quality as the bandwidth is used wherever needed.
Your problem was, single layer DVD. As the output media lacks space , the program you used lowered quality to fit 4.7 gb media. You should use dual layer DVD or 2 DVDs (which seems like bad idea)
I am on Mac so I really forgot/don't watch Windows/Linux programs but there is one program I can blindly suggest: TGMpegEnc. I have even seen it used in purely professional production work on windows based studios. Don't let its "plain" look trick you. It is a very advanced solution which I heard "basic" version is free.