Frequently Asked Questions (FAQ)

Below is a list of the questions I am asked frequently - probably not complete ;-) but I will extend it as time goes by..

General

  1. Why is it called "RatDVD"?
  2. How can I play back RatDVDs? Do I really need Media Player 10?
  3. Does RatDVD handle copy protected DVDs?
  4. Will HDTV be supported?
  5. Is there/Will there be any hardware that can handle RatDVD without re-conversion?
  6. What are the system requirements for using RatDVD?
  7. Why didn't you do your own player?
  8. How can I update my RatDVD version?

Technical

  1. Why didn't you use a standard codec like XviD, H264?
  2. Are there any more details about the Video codec you are using?
  3. What is AC-3 VS?
  4. Is the reconverted RatDVD (to DVD) as good as the original?
  5. Is there any specification or additional technical data available on the RatDVD files and/or components?
  6. What is "Virtual 2-Pass"?
  7. How about rate control/size prediction?

Usage

  1. Can I keep everything from the original DVD?
  2. How are the quality settings working?
  3. Can the file size of the .RatDVD file be estimated in constant quality encoding? What is the typical file size/compression level from DVD as source?
  4. Does the reconverted DVD-Video data (from .RatDVD) always fill the target media (single layer and double layer)?
  5. When I select a (Main or Extras) root, node less audio tracks are displayed than when I select an individual title. Why?
  6. Sometimes no title or the wrong title is displayed under "main movie"
  7. Where can I enable SP/DIF output?
  8. Can I display the tagging information in the Windows Explorer?
  9. Can I search through the tagging of all my movies?
  10. Is it helpful to compress the DVDs with DVDShrink, Rcode, etc. before using RatDVD?

Problems and solutions

  1. Is there a forum for RatDVD? Do you give support?
  2. RatDVD does not install
  3. I downloaded a RatDVD but it does not play back
  4. I tried to convert a RatDVD back to DVD and get errors while burning with my burning program
  5. A reconverted RatDVD (to DVD) does not play back
  6. I am unable to convert a DVD into the RatDVD format
  7. Playback in Zoom Player does not work
  8. Playback of RatDVD on my machine stutters. XVID files play fine.
  9. Sometimes the preview picture during converting is just black. Do I have to cancel?
  10. I have an old graphics card and preview does not work at resolutions higher than 800x600
  11. I see blocks during RatDVD playback on my PC. The "unratted" DVD is fine. What is wrong?
  12. I don't get cover thumbnails under Windows 2000. What can I do?
  13. When I attempt to play back a RatDVD, Media Player is looking for a codec and plays back without audio
  14. Are there known problems with DVDs created with DVDShrink, Recode or the like?
  15. I can't edit tagging in RatDVDs that already include tagging
  16. The ISO file that I created is not accepted by emulation/burning programs
  17. I don't have the option to burn/create ISO files
  18. I have Nero installed but my recorder does not show up in the list
  19. I would like the program in my own language. Do you plan to support it?

Misc

  1. Can I redistribute RatDVD?
  2. Am I allowed to use the RatDVD components in my programs?
  3. Is RatDVD open/shared source? Is it GPL? Does it install GPLed software?
  4. Why do some programs display the removed audio tracks when a DVD created form a RatDVD is loaded?
  5. How about XBOX. Do you consider porting it?
  6. How about Linux? Will you do a port?
  7. How about Mac? Porting?
  8. How about porting to PDAs and mobile phones?
  9. Is RatDVD available in other languages than english?
  10. Why do you require a DVD player installed on the system?
  11. I develop a software player. Can I use the RatDVD filters for my player?

Known Issues

  1. Seeking in media player appears to be strange


General

Why is it called "RatDVD"?

According to Chinese legend, the twelve animals of the zodiac quarreled one day as to who was to head the cycle of years. The gods were asked to decide and they held a contest: whoever was to reach the opposite bank of the river would be first, and the rest of the animals would receive their years according to their finish. All the twelve animals gathered at the river bank and jumped in. Unknown to the ox, the rat had jumped upon his back. As the ox was about to jump ashore, the rat jumped off the ox's back, and won the race. The pig, who was very lazy, ended up last. That is why the rat is the first year of the animal cycle, the ox second, and the pig last.

In old Japan, rats had it good because a white rat was a messenger of one of the seven gods of luck, Daikoku. Because of this connection, they were not killed. The story goes that a rat couple wanted the strongest husband in the world for their daughter. They asked the sun who declined saying that clouds had more power because they could cover him up. When they asked a cloud, he responded, "The wind is stronger than I because it can blow me away." The wind could not make the grade either. "The wall stops me cold," he said. And the wall, though honored by the offer wailed, "The rat is stronger. He can bore a hole right through me." So the couple wisely gave their daughter in marriage to another rat who was indeed the strongest creature of them all.

For everyone who doesn't like rats, think of it as an abbreviation:

  • English: Real advanced technology
  • Danish: Rigtig avanceret teknologi
  • Russian: ??????? ?????????????? ??????????
  • German: Recht abgefahrene Technologie
  • French: Réelle avancée technologique

Any other languages? Let me know.

How can I play back RatDVDs? Do I really need Media Player?

RatDVDs is a special format that due to its advanced features needs a special set of filters for playback. These playback filters get installed when you install RatDVD and register in the system.

Once they are registered every player can use them. One player which does this is Windows Media Player. Other players often need some modifications in order to "understand" the RatDVD extension and so uselize the correct filters. If a player does not work this is probably because he does not "know" the .RatDVD extension and uses the wrong set of filters.

If you are a developer of a player you might want to use the RatDVD filters which I have released for download here . Everyone is welcome to use it as he wants - if you have questions regarding the integration contact me at the email address below. Once you integrated RatDVD playback into your player, let me know so that I can put it on my site.

So, in summary, currently there are not that many players that do the playback but it should only be a days work to integrate it into a player that can work with DirectShow filters. Regarding the DVD Player "requirement" please read here .

Does RatDVD handle copy protected DVDs?

RatDVD does not support copy protected media directly but it allows to use decrypted content (e.g. from DVD Decryptor, AnyDVD, etc.).

Will HDTV be supported?

I like HDTV. I will probably support it once there is a standard. The codecs are all able to handle it already.

Is there/Will there be any hardware that can handle RatDVD without re-conversion?

Yes. The first manufacturer is working on it and probably there will be more in the future. But even if you don't own a DVD Player with mative playback RatDVDs can always be converted back to the original DVD which plays on every DVD-Player.

What are the system requirements for using RatDVD?

I didn't do a lot of testing on slow machines. However, I would guess that it starts to make fun at about 2600 MHz, 256MB RAM (512MB recommended) and an OK graphics card. Slower machines work also but take a lot longer to rat and unrat and playback may not be smooth.

Why didn't you do your own player?

I think there are already so many good players available and creating another one for just one different type of file would only be confusing. In my opinion it would be best that every player supports every format (that makes sense). I think with the components that can be found here it should be very easy for everyone to integrate .RatDVD into every player. So everyone can use the player he likes best and still have the advantages of the .RatDVD format.

How can I update my RatDVD version?

Exit RatDVD and Windows Media Player and just install the new RatDVD version. If something does not work a reboot might help.

Technical

Why didn't you use a standard codec like XviD, H264?

There are three main reasons I have my own codec. First, I needed to store many of the original MPEG2 features to restore the original. Second, I had this idea that a real transcoder would be better than a decoder/encoder approach. Third, H.264 and XviD (and other standard codecs) are covered by a wide range of patents and patent pools and I wanted to keep the program completely free.

Are there any more details about the Video codec you are using?

RatDVD uses a video codec called XEB. This codec is the result from an experimental project I did with some fellows and that does not use any XviD, x.264, etc. code although by the very nature of it contains routines which is similar in function and even to a small extend in output to what you'll find out there - obviously I didn't reinvent video-encoding. Since I have been asked here is a small summary of the codec internals:

  • It is block based (No wavelets anywhere)
  • It has a dynamic GOP structure, P frames have only one reference frame, B frames two.
  • GOPs are significantly longer than normal DVD GOPs and always closed
  • To avoid drift in long GOPs it has a build-in intra-refresh mechanism
  • It has intra prediction significantly more advanced than MPEG2, but not quite as flexible as H.264
  • It uses an integer transformation that approximates DCT
  • It uses a piecewise linear adaptive quant. The Quant level is determined for each macroblock by a simple psycho visual model
  • It has a primitive in-loop deblocking filter
  • Mode decision is part lagrangian optimization, part ad hoc based on statistics manually tuned to fit.
  • It uses an in-codec scaler and the actual encoded picture size can vary in both dimensions between GOPs
  • In order to maintain navigation ability and the reconvertability the codec suffers some limitations that others don't
  • The MUX format is H.262 + some private extensions

The main reason for this codec was the ability to transport the complete DVD navigation data to be able to recreate the original DVDs. Now that this goal is reached I can look in more detail at the performance and quality optimizations since I believe that there is still a lot more potential.

What is AC-3 VS?

Dolby Virtual Surround AC-3 uses the way your ears works to generate a surround feeling from a 2-channel signal. By using Virtual Surround you're able to drop the AC3 bitrate from 384 Kbit/s down to 192kbit/s, while maintaining the surround feeling and superior quality. The best audio is uncompressed LPCM which is rare on DVD's and consumes massive bitrate - especially in a surround configuration (I've never seen a surround LPCM DVD although it's within the spec to make one). Second best is the DTS format. Unfortunately DTS is very expensive in bitrate and isn't supported by all devices. Insignificantly worse than DTS is 5.1 AC3 which is typically 384 Kbit/s. Obviously 384 kbit/s is around 170 megabyte per hour of movie per audio track which may still be too much. For this situation AC3 VS is a great solution as it gives decent surround performance but at half the bitrate. Other Audio formats like MP3, Ogg-vorbis and so forth, have the significant disadvantage that they're not supported by stand alone DVD players which would mean a second conversion step would be required with a second step of generation loss. Also they are not designed for surround. Therefore if bitrate is an issue AC-3 Virtual Surround is an ideal solution.

Is the reconverted RatDVD (to DVD) as good as the original?

Yes! There might be some small limitations to the quality based on the settings chosen, but it is a fully functional, compatible, high quality DVD-Video.

Is there any specification or additional technical data available on the RatDVD files and/or components?

Yes. Search on the web for details.

What is "Virtual 2-Pass"

Virtual 2-pass significantly improves the way bitrate is distributed and the encoder decisions are made while recreating a DVD. The way it works is that when you're creating a RatDVD, the DVD2XEB transcoder will collect information about the video much in the same way a real two pass encoder would collect information in the first pass. Obviously the DVD2XEB transcoder doesn't encode everything into MPEG2 just to generate 1st pass information (due to speed limitations) and also due to size constraints the amounts of information that is stored as 1st pass information is limited - hence the "Virtual 2-pass".

How about rate control/size prediction?

The current version does only do constant quality encoding. Unlike conventional codecs like DivX, XviD, etc. the concept of RatDVD is that it is shared over the net and than used directly or reconverted into the original DVD. There is never really a need to get in on one or two CDs for playback. Especially not if you consider that you need to limit the quality for doing this. If you want it on a physical media - just use a DVD. One DVD+/-R is probably cheaper than two CDs anyway.

On the other hand, size prediction comes in handy when you somehow need a defined size (be it only that you want to store 400 movie DVDs on your harddisk). I will put it in an upcoming version.

Usage

Can I keep everything from the original DVD?

Absolutely!

How are the quality settings working?

The video encoder uses an adaptive quantization scheme which uses a psycho visual perceptive model so that it quantizes the most where you're the least likely to see it. The "average quant" generated by this model is what is wired to the quality setting parameter (inversed to generate an intuitive user experience). The closer to 120 (The closer the average quant is to 0) the more accurate will the pictures be and the better it'll look obviously the bitrate will climb too. It's a constant quality encoder and this means that it'll carry through on the quality setting no matter what bitrate that might produce. Constant quality transcoding is by far advantagous quality wise over rate control schemes however it tends to be more difficult to predict the bitrate of the output. I'll probably add a real rate control soon. Another important thing in the moment is that the codec is optimized most for medium settings around 100. Higer qualities get better but there is probably still room for improovement.

Can the file size of the .RatDVD file be estimated in Constant quality encoding? What is the typical file size/compression level from DVD as source?

No! Constant means that every frame in the video gets the bitrate it needs. This ensures the highest possible quality but means that the size of the converted video greatly depends on the video material. Interestingly there is almost no relation to the original DVD size - only the quantity of frames in the original is of some meaning.

I chose Constant Quality as the first Transcoding Method because I am a fan of the highest possible quality and compared to DivX, XviD, etc. in RatDVD there is no need to fit the file more or less exactly to a CD - because when it gets played back in a DVD player it gets blown up to a DVD anyways.

Does the reconverted DVD-Video data (from .RatDVD) always fill the target media (single layer and double layer)?

No. RatDVD always tries to reach the best possible video data for the size given. However, there may be cases where even with the best possible quality not enough video is available to fill the whole DVD. Especially when the target is 9GB double layer it will probably not fill the disc - but still have the optimum quality.

When I select a (Main or Extras) root node less audio tracks are displayed than when I select an individual title. Why?

The audio tracks in the root nodes are grouped. Audio tracks with the same data are shown only once.

Sometimes no title or the wrong title is displayed under "main movie"

The movie which is displayed under main movieis selected only according to its size. In certain cases the main movie is too small to be selected automatically. This may happen if the main movie is very short or it is constructed out of different smaller titles or the "extras" may acutally be longer.

Where can I enable SP/DIF output?

You can enable SP/DIF in the RatDVD Settings program. Make sure that you enable this option only if you have an installed/working SP/DIF output on your system. Otherwise you will not get any sound.

Can I display the tagging information in the Windows Explorer?

Well, the cover is displayed when you switch to thumbnail view. As for the other information you would need a special shell extension. I am thinking about doing one but I have no idea on when I will get to this.

Can I search through the tagging of all my movies?

Not yet. I am thinking of making an extension for the Windows "search" function but I have no idea when.

Is it helpful to compress the DVDs with DVDShrink, Rcode, etc. before using RatDVD?

Absolutely No! These programs compress the DVDs already on cost of quality. You'll get a RatDVD with a higher quality at a better compression/size ratio if you use the original DVDs as input material. Furthermore the resulting DVDs compressed with these programs are known to contain some structural errors that may cause errors when converting into RatDVD, playing a RatDVD or converting from RatDVD to DVD. See here for more details.

Problems and solutions

Is there a forum for RatDVD? Do you give support?

There is a forum at AfterDawn and cdfreaks . I will not give direct support and please don't email me for support issues. However, I will frequently look in both forums and fix what comes up.

Don't write me any emails about support issues. They will not be answered!

RatDVD does not install.

RatDVD requires WinXP/Windows 2000, DirectX 9 and a RatDVD compatible player like Windows Media Player.

I downloaded a RatDVD but it does not play back.

Make sure you have RatDVD installed and you have WinXP/Windows 2000, DirectX9 and a RatDVD compatible player like Windows Media Player installed.

I try to convert a RatDVD back to DVD and get errors while burning with my burning program.

The DVD-Video files created by RatDVD are 100% compatible. Please refer to the support of your burning program for specific burning errors.

A reconverted RatDVD (to DVD) does not play back

This might be a media problem or a problem with the burning program. Try burning another DVD on a +/-R media and see if the error is consistent. If you get the same error at the same position again, a media error is unlikely.

I am unable to convert a DVD into the RatDVD format.

Make sure that the DVD-Video data you use is not copy protected.

Playback in Zoom Player does not work

Since Zoom Player does not render the graph it needs to know which filters to use. To fix this you have to copy this file into the "MediaGraph" subdirectory and set "Management" to "Auto by extension" in the advanced options.

Playback of RatDVD on my machine stutters. XVID files play fine.

RatDVD uses a lot more processor power than XVID due to its higher compression ratio. Although different, it can probably be best compared to H.264 with all options enabled - both in speed and in quality.

One thing that slows down the playback is the scaling done by the CPU. With the RatDVD settings program you can turn this of and let it do the graphics card. Depending on your card, it may look better or worse.

There will be more things possible in speed optimization in the future...

Sometimes the preview picture during converting is just black. Do I have to cancel?

This sometimes happens if no display resources were available. In this case RatDVD doesn't try to display any more preview pictures. The "ratting" or "unratting" still works fine.

I have an old graphics card and preview does not work at resolutions higher than 800x600.

RatDVD always uses an overlay for preview. Older graphics cards don't have enough memory for the overlay at higher resolutions than 800x600. This happens only with really old hardware (e.g. PCI video cards).

I see blocks during RatDVD playback on my PC. The "unratted" DVD is fine. What is wrong?

With default settings RatDVD uses the graphics card for some calculations. On some graphics cards this looks considerably worse than on others. In this case you can try to enable "High quality scaling during playback" in the settings program. This setting will cause your CPU to do the calculations which results in a higher CPU load and so might cause stuttering on slower systems.

I don't get cover thumbnails under Windows 2000. What can I do?

Make sure that your RatDVDs include tagging information. If they do make sure that you GDI+ installed. In case you haven't you can download this from http://www.microsoft.com/downloads/details.aspx?FamilyID=6a63ab9c-df12-4d41-933c-be590feaa05a&DisplayLang=en . Please note that GDI+ has to be installed BEFORE INSTALLING RatDVD.

When I attempt to play back a RatDVD, Media Player is looking for a codec and plays back without audio

Probably you enabled the SP/DIF output in the settings tool but your computer doesn't support SP/DIF output due to missing hardware/software components. Disabling SP/DIF output solves the problem.

Are there known problems with DVDs created with DVDShrink, Recode or the like?

Yes. First, if you don't use the original but a DVD created with DVDShink, Recode (and probably other programs like these) you'll get less quality and a less good compression/size ratio.

Secondly these discs often have some errors that cause problems when converting into RatDVD, playing a RatDVD or converting from RatDVD to DVD. Especially if you cut out video material the DVD structures tend to get harmed.

I have worked around some (hopefully most) of these problems but since I am not aware about all versions of these programs I strongly suggest to use the original DVD data as input.

I can't edit tagging in RatDVDs that already include tagging

Yes, currently you can edit the tagging only if you add it. I will probably add more editing capabilities in one of the next versions.

The ISO file that I created is not accepted by emulation/burning programs

RatDVD currently uses the Nero engine to create ISO files. These files start with a 150 sec. pre-gap which is somehow unusual and not accepted by some programs.

I don't have the option to burn/create ISO files

Probably you don't have Nero 6 installed. Earlier versions may work - I don't know.

I have Nero installed but my recorder does not show up in the list

Make sure the recorder is found by Nero and Nero can burn without problems. For further support check the Nero web site .

I would like the program in my own language. Do you plan to support it?

RatDVD is prepared for translations and if you want you can do your own translation.

Misc

Can I redistribute RatDVD?

Yes, but please include a link to this site ( http://www.RatDVD.ca ).

Am I allowed to use the RatDVD components in my programs?

Yes, but only non-commercially.

Is RatDVD open/shared source? Is it GPL? Does it install GPLed software?

When you install RatDVD with default options you also install two separate programs that are under the GPL license. These programs handle tagging and navigation and you may unselect them during install if you don't need it or just don't want to use GPLed software.

RatDVD itself does not relate in any way to GPL and is currently not open/shared source. When I release it as open source some time in the future this will probably happen under the BSD license since this does not impose as many restrictions on the users as GPL does.

Why do some programs display the removed audio tracks when a DVD created from a RatDVD is loaded?

To keep the highest possible compatibility, only the navigation structure is corrected to address the removed stream, but the stream itself still exists - although as an empty stream. Programs that don't do a content analysis are likely to display the removed stream.

How about XBOX. Do you consider porting it?

Absolutely YES. I own an XBOX myself and use XBMC but unfortunately I have no idea how to do it and I have big concerns that the hardware of the XBOX is too slow. XBOX 360 four sure would be a target. We will see.

How about Linux? Will you do a port?

I would be interested into doing a Linux port. However, since I am an ignorant Windows nerd I have no idea how it can be done. What I will do is releasing more and more components as open source over time and so people, who know what they are doing can work on it.

One thing I do know is that porting the UI is probably not hard since it is Delphi and can be recompiled with Kylix relatively simple. The bigger problem is that the underlying architecture is based on DirectShow filters and so probably needs a lot of changes.

How about Mac? Porting?

Well, again I have to say it sounds intriguing but Mac is totally unknown to me. But hey, if there are people who are interested in it and I get a little more time, why not - although I fear thiswill be more a rewrite than a port ( see here, why ).

How about porting to PDAs and mobile phones?

That would be great. However, without a total rewrite this seems to be possible only for the latest MS smart phones and Pocket PCs (because of architecture and performance). Didn't get a chance to look into it enough in the moment.

Is RatDVD available in other languages than english?

Yes. Additional languages are added as translations become available.

Why do you require a DVD player installed on the system?

The DVD player is useful to play back the "unratted" .RatDVD file - meaning the recreated original DVD out of a RatDVD. It MAY play back also RatDVDs once it utilizes the RatDVD filters (e.g. by rendering) but this will be different from player to player.

I develop a software player. Can I use the RatDVD filters for my player?

Yes, absolutely. Feel also free to contact me at the email address below if you are having any problems, questions or you need anything special.

Known Issues

Seeking in media player appears to be strange

Currently you can only seek in the actual title. The start for the actual title is always at the zero (0) position of the seek bar. Since Media Player does not know when a new title starts (see here ), it does not reset the seek bar, so don't wonder about that for now.