Is there a big picture quality difference between VCD and SVCD?

[powerMarkymark]

I want to watch a DivX on my home entertainment DVD player.

My home entertainment DVD player supports both VCD and SVCD. I was wondering if I should have a preference to which format to encode it?

I've read up a little bit and suposedly SVCD is a higher quality, but in the real world is there a big picture quality difference between VCD and SVCD?

TIA

Mark

These guides describes how to convert(encode) a video to a VCD MPEG file that can be burned to VCD and played on almost all DVD Players.

 

[Spicedaddy]

Yes, SVCD with a decent bitrate (at least 1800kbps) is much better. It uses MPEG2, the same format as DVDs, while VCD is MPEG1.

 

[oldfart]

Huge difference. VCD looks pretty bad. As SD said, SVCD looks good as long as the bitrate is good. I use TMPGEnc to encode using 2 pass VBR. Another option is CVD. Its like SVCD, but at a lower resolution, which allows a higher bitrate. I haven't tried it out yet, but it is supposed to be good.

 

[rbV5]

No suposedly about it, SVCD does have more resolution and the same source files will be of higher quality encoded to SVCD than VCD IF they exceed VCD's resolution to begin with (352X240 1150 kbit/sec MPEG-1 NTSC)

Here is a link that shows differences in resolution in an easy to see fashion, unfortunately the 2 discussed in this thread aren't represented, but a comparison between broadcast and VHS gives somewhat an idea, however SVCD is a bit better than broadcast and VCD is a bit worse than VHS

 

[oldfart]

Its actually more the bitrate than resolution. The 1150 CBR bitrate is what makes VCD look so bad. SVCD can go over 2500 in either CBR or VBR.

 

[rbV5]

Its actually more the bitrate than resolution. The 1150 CBR bitrate is what makes VCD look so bad. SVCD can go over 2500 in either CBR or VBR.

Its both, but you're right...for an extreme example try using SVCD's higher resolution 480X480 with VCD's lower bitrate, it would give you much worse quality than the VCD resolution at the same bitrate, but to illustrate that resolution does matter as well, MOST of the time a file encoded at SVCD's resolution and bitrate will look better than the same file encoded at VCD's lower resolution, but SVCD's higher bitrate. The extra bits for encoding just can't make up for the extra lines of resolution.

 

[oldfart]

I've got to make a CVD and see how it looks. It's basically an SVCD with 352 x 240 VCD resolution and 48 KHz audio. Supposedly, it can look better than SVCD due to the higher average bitrate available due to the lower resolution. I'm skeptical because of just what you mention.

VCDHelp says this:

What is CVD then?
CVD is basically the same as SVCD but with a lower video resolution. Using a lower resolution you get more data for each pixel which means less mpeg artifacts such as blockiness compared to a SVCD with the same bitrate, but you will lose some sharpness. Most SVCD capable standalone DVD Players supports CVD.

That makes perfect sense. Less sharpness due to lower resolution, but also less compression artifacts due to higher bitrate. I think it also depends on how much video you want to squeeze on one CD. The longer the video, the lower the average bitrate. If you are only putting 30 - 40 min on the disc, it's easy to keep the bitrate high. With 1 Hr, it's a real challenge.

 

[rbV5]

You know, thats what makes video so interesting to me, there really is no right answer for every situation. I do all my real time Divx captures using 320x240 due to interlacing artifacts, and the quality is quite good, but where you really notice is during pans...compared to full 480 lines, it just has a distracting jerky quality. With multi-pass encoding, I always use full 480 lines, it just seems to me the final video is smoother and more pleasant, but I haven't actually tried CVD yet however. Right now I'm putting together my new rig, which will include DV and HDTV and a DVD burner, so I'm going to be using much better source material, and vastly improved display capabilities, so I've been starting to re-evalute my whole process <again>

 

[tart666]

it just has a distracting jerky quality

I have always thought the jerking came from the frame rate mismatch.

Sometimes I see Divx files encoded at 24 fps, while the original was 30 fps (NTSC TV). Or the other way around.

In fact, you can see double frames every 6th frame if the rate has been upped during encoding.

What is the other mechanism that creates the jerking?? I don't see how low res would make things jerky

 

[rbV5]

I don't see how low res would make things jerky

Its from capturing interlaced sources, when you capture at 240 lines (320 x 240) you are in effect capturing only 1 field (either the odd or even scanlines only) of the 2 fields used to create a single frame. The result is that you eliminate interlacing artifacts (these are created when the difference between the two "fields" have a significant change such as during action, or pan shots for instance) you'll see these artifactly plainly while playing the file back on a progressive display (computer monitor, what we are doing here), but not at all with an interlaced display (TV set). The downside is you lose half your scan lines, and since those represent fully one of the 2 fields used to create the original frame (originally they are displayed every 1/60 second for 30 FPS NTSC to eliminate flicker), during action or panning, the information that created the artifacts previously, are now gone, the reult is "jerky motion". When you capture the full 480 lines you deal with the interlacing artifacts with a deinterlacer, reducing or eliminating the artifacts, while keeping both fields..the result during action or pan shots, is now you have the information from both fields to blend the action together and smoother final video.

I have always thought the jerking came from the frame rate mismatch. Sometimes I see Divx files encoded at 24 fps, while the original was 30 fps (NTSC TV). Or the other way around.

I have been describing the process when encoding at the same framerate as your source, of course if you encode at a frame rate different than your source material, you will have trouble unless you handle it properly.Here is a link that has a much better explanation than I can give, it also illustrates interlacing, filelds and progressive scan very nicely.