DVD Quality Video

vbimport

#1

Does anyone know if there are any technical specifications that identify the quality of a video. That is, apart from conducting a visual assessment of the quality of a video, can I determine if a movie is DVD retail quality or VHS quality prior to viewing it?


#2

You have to view it to determine the quality.


#3

So as far as you know, viewing the video is the only way the quality of the video can be determined?


#4

Hi Damo12,

DVD-9 is a dual layer DVD. i.e 9.4 GB is taken for the DVD movie and hence tends to be better quality than a DVD-5 which is a single layer Dvd i.e. the movie exists on a single layer(4.7 GB). Then there is Widescreen which tends to have a better quality than Pan and Scan. There is also the fact that NTSC DVD’s are encoded better than Pal DVD’s. Also there may be subtitles on some DVd’s. Then there is the fact that if there are more than one audio stream present, it results in a crappy quality of the Video stream especially on a DVD-5. If there are more than a single movie present on the disc, it is a good indictor that the video stream encoding is not the best it can be, especially if it is DVD-5.


#5

Check this out: http://www.videohelp.com/dvd

And this: http://www.dvddemystified.com/dvdfaq.html

I think the most pertinent information would be resolution and bitrate. In the page I linked to, it’s not explicily stated, but comparisons with other formats use the bitrate figure of ~5000kbps and above for DVD. That’s a pretty good minimum figure for a commercial quality DVD, less than that and it’s likely you’ll be able to detect artifacting of some sort. (If you’re alert and know what to look for. Also, your display must be adequate. This of course, excludes those folks who claim no difference from original with a 40% backup in DVDShrink. :stuck_out_tongue: )

Here’s a free, bare-bones bitrate viewer:

http://www.videohelp.com/tools?tool=DVD_Bit_Rate_Viewer

What you’re most interested in is the average. (The bitrate should of course be VBR for best quality). As to resolution, for example Media Player Classic can show you this if you right-click the screen and then View -> Information. Any commercial, pressed DVD from a major studio should be 720x480/576, but I suppose you never know. There are other, smaller legal resolutions for DVD.

Now, a DVD may qualify per the above and still be encoded badly, it happens.

[EDIT] I should clarify my statement about artifacting. According to DVDDemystified, artifacting may “occasionally” be noticeable anywhere from ~3.5 to ~6 Mbps. Much depends on the source, that is, how much “action” there is. A talking heads movie may be fine right down to 3.5 Mbps. But ~5 Mbps is a pretty good bitrate for full D1.