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schizo
7th November 2002, 15:44
The situation:
I have several SVCD-encoded movies that I would like to play on my Pioneer DV-626 player. This player does not SVCD formats, but it does play VCD with MPEG2 files.

Okay, based on previous articles in this and other forums, I've gotten to the point where I can successfully make a 'fake' VCD with the unmodified MPEG2 source on it, however my particular player (and many others as well) do not stretch the MPEG2 video to fill the screen, making the video appear squashed to the left.

By reading other articles related to DVD-R with SVCD content, I gather that this problem can be solved by adding pan and scan information to the MPEG2 stream so that the player knows how to properly present the images fullscreen.

Unfortunately I've only found references to one single program that can actually insert this P&S information, which is PixelTools' MpegRepair. This program is 1: expensive, and 2: extremely time-consuming when adding the pan and scan information.

Now, being largely ignorant of the more arcane aspects of MPEG2 creation, I still feel that there ought to be a better, cheaper and faster way of achieving my desired result, ie a VCD with MPEG2 content that will play back full frame widescreen content.

So; pointers, guides and helpful tips are much appreciated.

to summarize: I need a way of tricking my DVD player into playing back a stream that is 480x480 or 512 in a DVD resolution of 720x480/512, preferably without re-encoding the entire MPEG2 stream, and it must work on a player that only supports VCD layouts.

Looking forward to your comments,

ScHiZ0

markrb
7th November 2002, 18:17
I am pretty sure you are going to have to re-encode the video stream.

Mark

Arianos
8th November 2002, 09:30
Shamelesly quoted from a VCDHelp user report on your player:

"You can play SVCD's when do following:
Use TMPEG. Under MPEG tools select the mpeg file you want to convert. Then change the type of mpeg stream to MPEG1 Video CD. Then rename the output file and select run. Takes about 5 to 10 minutes. Now the player knows the CD as VCD and plays the SVCD perfectely. "

schizo
8th November 2002, 10:43
Well yes, and this is what I've done. It does indeed play the movie perfectly, except for one problem: the video is played back in its original resolution (ie 480x480) which means that only 480/720=2/3rds of the screen is used. This produces a square picture on a widescreen TV with content that ought to have been played back 16:9, which means that it's squashed up.

Aparently, one way of getting around this is to add pan and scan information to the mpeg stream, with a vertical "viewscreen" equal to the vertical resolution of the movie, and setting up your DVD-player to play pan and scan rather than widescreen.


A slight update: it appears that remstream can add pan and scan as well, so I'll test if this produces the desired result, meanwhile anyone else who has found and fixed this problem please post your solution.

UltimateDBZ
8th November 2002, 16:39
I'm not very educated in the VCD area (SVCDs are my backyard), but I doubt you're going to be able to trick your DVD into playing an SVCD that's encoded in VCD resolution, at DVD resolution. It doesn't really sounds feasible...

schizo
11th November 2002, 10:22
The movie is still in svcd resolution, ie 480x480 (NTSC). The VCD trick is merely a workaround for the lack of support for SVCD layout in my player, and encoding is left unchanged (still mpeg2 in other words). I am guessing here, but the DVD player seems to handle the content as if it were a DVD, since it's not stretching the image properly to fill the screen (if it thought the stream was VCD then 480 vertical res. is actually 1.5 times more than expected, and the image ought to have been cropped rather than squashed :confused: ).

Anyway, it has been pointed out in other threads that the reason that many DVD-players don't play back these faked VCDs in fullscreen is because the player expects the content to be in a DVD-compliant resolution (ie 720x480) and when only 480 pixels are available the image ends up being squashed. Adding pan & scan information to the video stream is apararently a way of working around this, since the player should then grab the middle 480 pixels (ie, the entire vertical frame) and display it fullscreen (thus playing back a widescreen movie in actual widesreen). Anyway, this is how I understand it - but if I'm wrong by all means correct me, as I'm definately not a professional movie digitizer.. :sly:

nexus_06
12th November 2002, 03:10
I tried it on my friends dvd and it worked fine the image was excelent but the playback was choppy and the audio out of sinc.

is it possible to fix this problem.