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View Full Version : All sorts of questions regarding dvd quality.


creaseycj
2014-10-22, 05:29 AM
I have a hand full of questions regarding my dvd bootlegs I have just acquired. I am new to collecting dvds but have been collecting audio for a little longer and that seems to be easier to diagnose whether its lossless and in its original source or not.

How am I supposed to know if a dvd is actually in it's original recorded quality?

How can I tell if a dvd has been up/down converted from it's original source?

What is a generation, like first, second, third, et cetera?

Is there really no true lossless video format?

I'm sure once people start posting and answering my questions I'll come up with more. For the time being that's all I have though and I appreciate all your help!!!

xjsb125
2014-10-22, 11:47 AM
As far as any video on DVD or Blu-Ray, it's got some compression applied to it to get it into the proper format for players to read. There are lossless codecs out there for video, but they aren't typically for your everyday viewing needs. Generations in terms of sources means how many times it has been dubbed from the original source. So if I recorded a show onto VHS today, that tape would be first generation. If I mailed it to a friend, and he copied it onto another blank tape, his tape would be second generation. Likewise with DVD, if I received one, then compressed the video to fit it on another disc with something else, it would become second generation. I'm not an expert on tracing quality like a lot of people are on here, so I can't answer that question very well. Hope that helps answer some of your questions. Welcome aboard!

creaseycj
2014-10-22, 04:47 PM
Thank you very much for the info and the welcome!

jabulon
2014-10-23, 04:23 AM
It's ten years old, The Ins and Outs of Video Compression (http://www.animemusicvideos.org/guides/avtech/video3.htm) but it's still a nice article about video compression.

Until today most video's are still lossy encoded (due to file size) although more and more (d)enconders are capable of lossless compression (http://en.wikipedia.org/wiki/List_of_codecs#Lossless_compression_2).

There is true uncompressed video, it's called CleanHDMI (http://en.wikipedia.org/wiki/Uncompressed_video)

(Wiki: http://en.wikipedia.org/wiki/Lossless_compression)

creaseycj
2014-10-23, 06:53 PM
What video codecs would be considered a poor option, like mov, avi, mpeg-1, et cetera?

How would I be able to tell what kind of codec/encoding is used on my dvd vob files?

So everyone know, most of my bootlegs range from 1985 to 1995 with some newer ones. Was there a standard back then that was used so I can more accurately compare two or three kinds of video so I can determine what kind of video it is and if it is a first, second, third generation?

xjsb125
2014-10-23, 08:57 PM
Older .mov was garbage. Most .mov files now use h.264 compression, and look pretty nice depending on the camera that created the files. .Avi can have a variety of codecs, and depending on what is used on the video, can be lossless, or compressed to the max to look like garbage. Your worst of the worst options would be mpeg-1, and .wmv. Your DVD's are going to be standard definition mpeg-2. As far as being able to tell generations, that's a little harder to do. Especially if it's a bootleg off of a consumer camcorder. They weren't the highest of quality back then. But, if the video colors are washed out, and the video itself is lacking in image detail, that would probably indicate it's been dubbed at least a couple of times. Text on the video that has been generated by a VCR is also a good indicator it's been through the wringer a couple of times. If you can find the same bootleg out there you might try downloading it and comparing image quality. If you find one that has a better image, then you may have found an earlier generation of the video. Most sites are also going to require some lineage to the video, so that may help you figure out where your copy is on the family tree.

creaseycj
2014-10-24, 06:12 PM
Is there any way to tell if a bootleg dvd has been ripped from Youtube? Some of my videos look similar but I really cant differentiate the differences between them.

lpmaskman
2014-10-25, 05:34 AM
Is there any way to tell if a bootleg dvd has been ripped from Youtube? Some of my videos look similar but I really cant differentiate the differences between them.

Search for that bootleg on YT and compare their pictures.

xjsb125
2014-10-27, 05:05 PM
The overall data size on the disc will probably be very low, unless whoever authored the DVD tried to "improve" the video by encoding it with a high, or constant bitrate. If the video was ripped from a 360p or 480p YouTube source, I would expect the video to be distorted and/or pixelated, especially if the original video was from a non-broadcast/professional source.