XVCD2, MPEG2 playback on non-SVCD compatible DVD players

[riksnet]

I found this out while having problems with mpeg1/vcd playback and it might help someone tring to achieve better quality VCDs.

If you take a MPEG2 file and use TMPgenc mpeg tools, then simple multiplex the MPEG2 file with the MPEG1 VCD format option (takes 3-5mins for 30mins video!)
then burn it with Nero in VCD format, You can play the MPEG2(hi-res) videos back with no problems.

So far this as been tested on a

Panasonic RV31 (480x576 upto 2.5mbs)
Sony DVP-S725D
Panasonic l40


for more info
http://www.long-distance-longdistance.com/phpBB/viewtopic.php?topic=486&forum=4&10

[Kdiddy]

I suggest reading here for whats truly happening

http://www.vcdhelp.com/phpBB/viewtopic.php?topic=64237&forum=3

[Truman]

Kdiddy you were right. They really expect better quality.

[DVD Master]

I saw an interesting article in other forum. This really works for me (my DVD player does not playback svcd).

http://rilanparty.com/vbb/showthread.php?s=&threadid=7291

[Kdiddy]

yeah I know, thats why I dont like it when people write misleading posts....just state the facts ya know, especially when "quality" is such a subjecttive matter.

[riksnet]

I think your problem is that you must enjoy waiting 5 hours or so for your software to encode the video into a format that works on your DVD player. But for me and other people who own a Hardware MPEG2 encoder this option a quick a excellent solution to create VERY GOOD! quailty playback on DVD players that don't recognise SVCD format.

Who cares what it is really doing and how it works, the fact is is that it works and many people are happy with that.




<font size=-1>[ This Message was edited by: riksnet on 2001-10-24 05:25:00 ]</font>

[DVD Master]

I am happy too...

[logar77]

Most definitelly....tried it last night by converting a svcd and it worked perfect. 20 seconds to convert and 10 min to burn is all it took. Now I can watch all the svcd releases(after converting) on my dvd. Comparing it with some 720x480 & 480x480 xvcd encodes I have done it actually looks better then the 480x480 and about the same as the 720x480....almost perfect dvd quality.

[Kdiddy]

Im glad that you are happy, but again, its not a SUPERIOR improvemnt over xVCD & its not as good as SVCD, period...if you are happy with it then fine, but ask yourself, if this method was TRULY such an ideal method froma pure QUALITY improvement standpoint...then what would be the point of the SVCD format period, if you supposely could get all the benefits of mpeg2 encoding as a VCD??, but again if you are happy with this method, then Im happy for you.

<font size=-1>[ This Message was edited by: Kdiddy on 2001-10-24 13:42:49 ]</font>

[DVD Master]

Logar77: What settings are you using? I used settings from "Anthony" in Doom9 and I can encode about 95 min with good quality. And yes you are right, it is a superior improvement over xVCD.

<font size=-1>[ This Message was edited by: DVD Master on 2001-10-24 18:02:07 ]</font>

[riksnet]

I have a question for kiddly(/trueman)

If has you say that the DVD player 'will try to interpret the video as mpeg-1 NOT mpeg-2' then could you please clear up something, why don't i have play back problems when:

1) i record the audio using 128K bit
2) (more importantly) my mpeg2 videos are all recorded using VBR!!

If all of this is also capable with MPEG1 then what is the difference between MPEG1 and MPEG2??

[Kdiddy]

Risknet: "If all of this is also capable with MPEG1 then what is the difference between MPEG1 and MPEG2??"

"MPEG1 Video can be distinguished from MPEG2 Video at the video sequence header, i.e. for MPEG2 Video a sequence_header() is followed by sequence_extension(). The particular profile and level of MPEG2 Video (MAIN_Profile@MAIN_Level, HIGH_Profile@HIGH_Level, etc) are determined by the profile_and_level_indicator field of the sequence_extension header of MPEG2 Video."
http://www.cis.ohio-state.edu/cgi-bin/rfc/rfc2038.html

"MPEG1 has an average compression rate of about 1.5 megabits per second (Mbps); the largest possible compression rate for MPEG1 is slightly more than 5 Mbps. MPEG2 bitrates fall between about 3Mbps and about 15Mbps. Interestingly, at bitrates below 3 Mbps, MPEG1 actually performs better than MPEG2. This is because the higher level of precision built into the MPEG2 algorithm requires more processing than MPEG1. At lower bitrates, the percentage difference is great enough to cause significant digital artifacts to appear in MPEG2 encoding that do not appear in MPEG1."
"At very low bitrates, however, in the range of 1.5 Mbps, MPEG1 is preferred to MPEG2."
http://www.d-co.com/digicaster-faq.html

"The MPEG video compression algorithm employs two basic techniques: block-based motion compensation for the reduction of the temporal redundancy, and transform domain (DCT) coding for the reduction of spatial redundancy. The motion compensation technique is applied both in the forward (causal) and backward (non-causal) direction. The remaining signal (prediction error) is coded using the transform-based technique. The motion predictors, called motion vectors, are transmitted together with the spatial information.
The MPEG-2 standard uses the same set of algorithms as MPEG-1, and has an additional support for interlaced video sources and scalability options. Although there are minor differences in the syntax, the MPEG-2 standard is conceptually a super-set of MPEG-1, and therefore we will describe both as the MPEG standard when the distinction is not necessary.
In this section, the basic architecture and algorithm of the MPEG standards are described. We first present the MPEG-1 standard, and then describe the additional functionality included in the MPEG-2 standard."
http://icsl.ee.washington.edu/~woobin/papers/General/node2.html


Again, ONLY as their encoding algorithms are concern, BUT more importantly at bitrate range between 1500-2000 at equal resolutions, they possess the same "perceptual" quality. This all Im saying nothing more...so outside of that, there are several differences.

Also, the audio has no effect on the video, whatever audio problems you are having should not differ whether using mpeg1 or mpeg2....explain this a little more, because Im not quite understanding what the audio aspect of this is?

[riksnet]

Actually from the question, i said that i DON'T have a problem either with audio or video,
the point i was trying to make was that in the XVCD section in VCDHELP.COM it quotes that XVCD (MPEG1) audio is set at 224kbits and and so i was trying to make the point that if my MPEG2 video was been decoded as a MPEG1 video then why was i not having audio problem when i use lower bit rates.

that was all, but thanks a lot for the explanation.

By the way just for reference i record my videos using 352X576 VBR(2mbs or 2.2mbs) 44.1Khz (128 or 196kbs)
-depending on video length

and i think just to conclude you will agree, weather i produced my videos in SVCD format or VCD format (using my method), If all the recording settings are the same it is difficult to say that one produces a better quality playback than the other.

Thanks again.



<font size=-1>[ This Message was edited by: riksnet on 2001-10-26 06:10:55 ]</font>

[Truman]

Since XVCD is not a standard and has no fixed specs, you are free to select any video or audio bitrate.