I saw in a store today several brands of blank DVD-R (Maxell, JVC, etc.) that claim that their disc could be recorded in either EP or SP mode and that one can get 4 hours of recording in EP mode and 2 hours in SP mode.
I went to another store and saw Imation DVD-R with even more fantastic claims about recording time ranging from 1 to 6 hour, depending on the speed (mode).
Would someone please enlighten this "out-of-date" brain , for I never thought this would be possible with DVD?
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I don't understand your question or confusion ..... so consider these things:
On some machines "EP" is 4-hour mode (like LITEON). On others, it's 6-hour mode (like JVC, where LP mode is 4 hours).
At any rate, "modes" are old-fashioned limited-comprehension ways to talk about video. Tape had modes, digital video is confined only by bitrate (quality is determined by its ratio to the resolution in use, and a few other factors like interlace).
DVD recorders often use "modes" to talk about how much you put on a disc. SP "mode" on most DVD recorders is 2 hours worth of video. In proper terms, it's 720x480 video with a bitrate of around 5.0-5.5Mb/s, interlaced MPEG-2 with AC3 audio.
There is also a differences between SL and DL media. SL (single layer) does 2 hours in "SP mode" while a DL (dual/double layer) could do 4 hours.
Sorry I did not make myself clear. Let me try again.
In the old days of video recording (VHS, Beta :P ), EP & SP referred to the speed at which video data were recorded on a tape and later played. The slower the speed, the lower the quality of the pictures, but one would get more time onto the same tape.
Now, the DVD makers mentionned in my post claim that one could make DVD in either EP or SP mode. They also claim that with EP mode, one would get twice the time of SP mode.
What I don't understand are:
1) Although a DVD can be burned at different speeds (1X to 16X), the amount of video put onto that disc remains the same. In other words, I can only record max 4.75 GB of video signals onto a DVD, no matter what speed I use to burn my disc.
How can those DVD makers make such claim?
2) When I burn my DVD discs, Nero does not give me any choice like EP or SP. The choices I have are the speeds of the disc and the burner. For example, if I use a 8-X disc in a up-to-16-X burner, the speeds available to me will be 1X, 2X, 4X and 8X.
Which software(s) would have EP & SP?
3) Both my DVD ROM and standalone player do not have any speed button/switch. When I put an EP-mode-recorded DVD into my machine, how does it recorgnize the proper speed?
Lordsmurf's reply spelled it all out. DVD recorder's use "modes" to indicate how much video you can get on a disk. It does not refer to the speed of the recording. It's the bitrate that controls how much you can fit on a disk. A lower bitrate will give more time at reduced quality.
Which part don't you get?"Art is making something out of nothing and selling it." - Frank Zappa
wouldnt be SOFTWARE per se that would have these options, it would be a standalone dvd recorder, as for how they offer the option, its very much similar to the idea of a VCR...they degrade the quality some to fit more onto the disc
Pardon me, but you can see I am a little "dense" on this subject.
1) EP & SP modes: which hardware and/or software would afford me these modes? A burner? A standalone? Or, both?
My DVD ROM and standalone DVD have no such modes.
2) Assuming that I have a video file of 8GB. Assume further that I want to fit that onto a single layer DVD (4.75GB). Can I use EP mode (assuming that I find such hardware) to accomplish that?
Also this information.
If speed is not involved here, how come I see this claim by Maxell? I am paraphasing the claim:
"Burning Maxell-R on EP mode on equipment not intended for such mode may damage the equipment."
I will go to the store and get the exact quote from Maxell tomorrow. :P
The video and audio on a DVD uses compression. The higher the compression the more (talking running time here) that you can fit on the DVD but the lower the quality. The less the compression the less (talking running time here again) that you can fit on the DVD but the higher the quality.
The compression is based on the bitrate used to encode the video. High bitrate means less compression. Low bitrate means more compression.
There is a limit to the bitrate that you can use for the DVD format. This limit is around 1 hour or 60 minutes. So anything from 1 minute up to 60 minutes is going to use the same high bitrate or the least amount of compression that the DVD format can use.
Once you go over 60 minutes you have to lower the bitrate (increase the compression) to get the video and audio to "fit" onto the disc. As an example ... a so-called 120 minute VHS tape could fit 2 hours if using the SP mode but if you used the LP mode it become 4 hours and if you used the SLP/EP mode it became 6 hours. The tape itself has a fixed physical "limit" in that the tape is "X" feet in length but SP recorded "faster" than EP which recorded "slower" and that is why EP could fit more onto the tape but EP mode also looked worse than SP mode due to the slower recording time which resulted in a lower quality image.
Well a DVD has a fixed size or capacity as well (in this case a single layer DVD is 4.7GB in marketing speak ... in the real world it is actually more like 4.37GB). However like a videotape you can fit anywhere from 1 hour up to 6 hours and sometimes even as much as 8 hours. If you use the highest possible bitrate then 1 hour can fill the DVD. If you use the 6 hour mode with the "proper" bitrate for that running time it will also fill up the DVD. The difference is that the 1 hour recording at max bitrate will look much better than the 6 hour recording because one is using more bitrate than the other.
There are other factors as well. DVD is digital and has a fixed resolution. However there are 3 main resolutions that the DVD format can use. There is Full D1 (which is 720x480 but can also be 704x480), there is Half D1 (which is 352x480) and then there is 352x240 which is the lowest.
The higher the resolution the more bitrate that is needed to ensure quality video so as the running time increases the resolution will change from Full D1 to Half D1 to finally 352x240.
For instance 1 hour at Full D1 looks very good. Full D1 looks good for 2 hours and beyond but even but once you get to around 2 1/2 hours the bitrate that must be used to "fit" the content to the DVD is very low so the recorder will switch from Full D1 to Half D1 as Half D1 needs less bitrate to look good. This may seem strange because Half D1 has less resolution than Full D1 so doesn't Full D1 look better?
Well it is true that Half D1 may look slightly softer than Full D1 due to the lack of resolution but when you use a low bitrate with Full D1 you get a lot of what is called "compression aritfacts" but since Half D1 needs less bitrate (due to the lower resolution used) you get a softer image but no "compression artifacts".
Usually Half D1 is only used up to around 4 hours on a DVD recorder. After that the bitrate is so low that it begins to look "ugly" (compression artifacts) so the 352x240 resolution is used as it needs to less bitrate. Unfortunately the step down from Half D1 to 352x240 is a much bigger step down in quality than Full D1 to Half D1 ... in short 352x240 looks bad resolution wise even if there are no "compression errors" and you will find that most people will not try to put more than 4 hours on a DVD as a result. In fact with most DVD recorders the "sweet spot" for "long" content is about the 3 hour point.
So in summary a DVD recorder uses recording modes to adjust the resolution and bitrate used so you can get "X" number of minutes onto a DVD disc. The longer the running time the less good the video will look. The best it can look is 1 hour or less. The "worst" that is usually considered tolerable is 3 or 4 hours. After 4 hours it looks BAD.
- John "FulciLives" Coleman
The resolutions given above are for NTSC video on a DVD. The PAL format uses a slightly different resolution but the concept is the same.
I think I have finally got it.
The terms HQ, SP, EP used by the DVD industry refer, not to the speed (like in the video tape industry), BUT to the bitrate that is used to create a DVD file.
HQ refers to the highest bitrate, SP the next highest bitrate, and so on.
The higher the bitrate, the higher the picture quality, the larger the file, the more space on a DVD disc it will take, and consequently, the less playing time the disc will have.
Conversely, the lower the bitrate, the lower the picture quality, the smaller the file, the less space on a DVD disc it will take and, of course, the longer playing time the disc will have.
Did I get it right?
That's kind of confusing, if not deceptive, for the industry to use these terms (HQ, SP, EP, etc.) since they are used to refer to the speed at which a video tape is recorded. This reminds me of my own confusion over the label RW on non-rewriteable DVD. Hm...
Thanks to all of you who took time to explain the subject to me.
This is the exact reason why I love this forum so much.
Someone had a question.
People took the time to explain (in several different ways) the answer.
Then the person who posted got the answer, understood it, and made a follow-up post thanking everyone who participated.
Doesn't get any better than that!
Originally Posted by moviebuff2
- John "FulciLives" Coleman