Hi-res dig JPG image losses when converting to svcd, why?

[ewingc]

I am confused when it comes to making slideshows from hi-resolution digital camera images. In every software program I have tried, you must encode to MPEG 1 or 2, I understand that this is the only formats DVD play. But why, if I have 1200x1600 digital jpegs, do they look so bad once converted to SVCD? Granted I am looking at them on a 57 inch screen TV. But why do commercial DVD's look so good on this TV when DVD quality is only 720x480, not that much more that SVCD.

I have tried Ulead Video Studio, Picture show2, MGI Studio, etc... they all seem to offer very similar quality once they convert to MPEG2. I can copy the hi resolution images directly onto a SVCD using NERO, but I am then limited to 99 pitures and no music.

Can someone explain why I cannot get high quality images on my TV versus what you get from DVD. Would I see this huge increase by buying a DVD writer and burning DVD's or will there still be loss of quality from the original pictures. Why can't I see these hi-res pictures clearly on my TV when they are originally of a higher resolution than the TV?

This is actually true of my VHS tapes that I have converted to SVCD also, using TMPGEnc and Nero. While they are viewable and semi-acceptable, they are actually of less quality than the original VHS. Is this just a problem with all the digital conversion going on? I can understand some capture issues here, but not on the digitial JPEGS as they start out digital.

Any help is appreciated!

Thanks!

[DivXExpert]

JPEGs are less compressed than a SVCD. As for why commercial DVDs look so good. Cause the bitrate is at least 3 times as high. Not to metion double the resolution.

The quality drop, is because the lack of bits per pixle. Nothing you can do about it. Go any higher and you DVD player may not support it.

[Vejita-sama]

Actually since he's making still images you he might be able to use bitrates above 2520kbit for his still pics. Also for x(S)VCD still images the standard calls for 704x480 (or 704x576 PAL).

[ewingc]

When you say the resolution is twice as high, could you explain how 720x480 is twice as high as 480x480? By my calculation it is 1.5 times as hi. Will this make the difference in seeing clearer pictures?

Also when you talk about the bitrate, can I set it higher. What is that actually doing when you play it back.

What do you mean by "the standard calls for 704x480". What standard do you speak of? How can I choose this format for NTSC. It seems that the only options I have on all these slideshow programs is either SVCD at 480x480 or DVD at 720 x 480. How could I get 704 x 480 on a SVCD?

I really appreciate your help.

[vitualis]

When you say the resolution is twice as high, could you explain how 720x480 is twice as high as 480x480? By my calculation it is 1.5 times as hi. Will this make the difference in seeing clearer pictures?

Maths...

Yes, you're right, 1.5 times the resolution.

What do you mean by "the standard calls for 704x480". What standard do you speak of?

The problem is that the programs you are using are converting your images into an MPEG video stream and for SVCD, you are limited to a framesize of 480x480 for video. If the mpeg encoder is also a little bit shoddy, it can look poor.

You should start using VCDEasy as it can encode MPEG Still Images which are used for both VCDs and SVCDs.

In both, the framesize/resolution for MPEG Still Images is 704x480 for NTSC discs. This is quite close to that for DVD (720x480).

If you convert your images into MPEG still images, they look brilliant on a TV (but the downside is that you won't get any cool looking transitions).

As for the "standard", we are talking about the VCD/SVCD standard.

I suggest that you get VCDEasy here: http://www.vcdeasy.org and to understand more about MPEG still images, read the relevant guide here: http://www.michaeltam.com

Also, have a look at the user guides section of this forum. There are a handful of guides on how to make "photo VCDs" using VCDEasy.

Regards.

[Nitemare]

You may get better results by resizing your pictures with an image editing program before encoding. Allowing the MPEG ancoder to resize them is probably less quality than feeding it a correctly sized pic.

704x480 is the correct size for MPEG stills, but some of that will be trimmed off by your TV.

[vitualis]

The resizing algorithms in VCDEasy are excellent and now they even contain an anti-flickering option!

As for the problem with overscan and the aspect ratio issue, VCDEasy can fix this as well when you make the stills.

Regards.

[ewingc]

Thanks, downloaded VCDEasy and was able to convert jpegs to sill mpegs. Is there anything I can do with these now or must I simply write them to SVCD. For example can I put them into slide show programs and add music and menus or will that simply re-encode them back to 480x480.

Is there any software that will allow me ato add sound tracks to still mpegs and create slide shows?

[vitualis]

Thanks, downloaded VCDEasy and was able to convert jpegs to sill mpegs. Is there anything I can do with these now or must I simply write them to SVCD. For example can I put them into slide show programs and add music and menus or will that simply re-encode them back to 480x480.

Now you have your MPEG still images, use VCDEasy to start a new project and import these still images!

With VCDEasy, you can also make menus, etc., but I suggest you start with something simple.

If you just import all your images, VCDEasy will make a S/VCD that will play each of the still images in turn for (I think) a default of 5 or 10 seconds before displaying the next clip.

When you get a handle on how VCDEasy works, I suggest you have a read of the many guides on this forum on using VCDEasy to create more involved menus. I suggest having a look at adam's guide on using VCDEasy to make complex menus.

For the ultimate control in the authoring process, I suggest manual XML authoring. For more info on that read the guides here: http://www.michaeltam.com

Is there any software that will allow me ato add sound tracks to still mpegs and create slide shows?

Unforutantely no. There are methods of adding audio to still images but I don't suggest you try them until you really know what you are doing.

Regards.