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View Full Version : Is there a way to determine whether a video is lossy .mpg sourced?


Salva Veritate
2007-08-13, 02:24 PM
Kind of a newbie question but I just got a show in the mail that has a logo I've seen on the widely distributed lossy .mpg version. Plus the video quality is suspect in itself, so I want to know if it's lossy.

The logo/label makes me think that the logo was edited on when it was distributed song by song as an .mpg file, plus the show has cuts that make it seven minutes shorter than the official source.

http://img519.imageshack.us/img519/5143/ragehultsfredrl1.jpg

Edit: I'm not including the image to use it as evidence, but more as a qualifier to my suspicions.

KoolKat
2007-08-13, 03:53 PM
Won't be able to tell absolutley anything from a jpg as jpg is a lossy format to start with.
Get G-spot program(its free) & put a file or large vob from the Video_TS folder in that.
Then show me the screenshot of what G-Spot reads.

Still may not show anything but it may be an authored VCD and i will tell you if G-spot tells me.

K_K

Salva Veritate
2007-08-13, 06:57 PM
http://img363.imageshack.us/img363/6610/gspotlolollck5.jpg

KoolKat
2007-08-14, 03:36 AM
Well that looks fine exept the 8000 can look questionable as that that tells me it is Constant bitrate(CBR).
This is not as good as VBR(variable) as it was recorded/transfered using only 1 pass.
Too much bitrate at wrong moments where not much is needed can cause blocking.
It could mean it was re-encoded using CBR but thats not concrete evidence.

Everything else checks out though.(the Mp2 audio would of been @<hidden> standard not 384.....that could be bad setting up though during transfer)
What do your eyes tell you?
Example: I recently recorded a TV re-broadcast of Sky live at Rockpalast.To me the image of the broadcast looked like a processed VCD.Maybe it was.Maybe thats all that exists now.


Remember that in reality there is no such thing as DvD quality as DvD stands for Digital Versatile Disc,not Video Disc.
You can't get x IN DvD ,only ON DvD
The disc is only a archive storage tool.
What counts on the quality of it is the resolution,bit-rate & copy generation.
Your eyes will tell you but they have to be trained ;)

I will say about the jpg you posted that i cant see many "compression tells" so it maybe lossless(for want of a better term) ..but just a higher generation copy.That's why the contours are not sharp anymore.


My personal opinion........re-encoded because of CBR & Mp2 @<hidden>

Hope that helps you a bit.

K_K

Salva Veritate
2007-08-18, 04:42 PM
Alright, thanks! :D

nineyemit
2007-11-23, 01:23 AM
Anyone Have a link to a place to download this program. Was hesitant to to do a search but did anyways. You can guess how many links there are that arn't for this program. . . :love: :booty: :naughty: :eek2: :redface:

diggrd
2007-11-23, 04:22 AM
http://www.headbands.com/gspot/
From the FAQ http://www.thetradersden.org/forums/faq.php?faq=new_faq_item#faq_software

showtaper
2007-11-23, 06:11 AM
Anyone Have a link to a place to download this program. Was hesitant to to do a search but did anyways. You can guess how many links there are that arn't for this program. . . :love: :booty: :naughty: :eek2: :redface:

I'll bet if you searched for +gspot +bitrate you'd get a lot less clit.....

Friday
2008-05-05, 03:16 PM
All widely used digital video formats including DVD (which is really MPEG, like the .mpg-file) are lossy. I think you have to rely on your eyes.