The Traders' Den  

  The Traders' Den > Where we go to learn ..... > Technobabble
 

Notices

Technobabble Post your general Need for Help questions here.
Lossy or Lossless?
Moderators

Reply
 
Thread Tools
  #1  
Old 2010-01-19, 06:35 AM
twinaleblood's Avatar
twinaleblood twinaleblood is offline
The Innovator Of Violence
155.90 GB/219.27 GB/1.41
 
Join Date: Jan 2009
How to detect lossy sourced dvds

Hi guys, hope somebody can help.
My question is: how can I detect whether or not a dvd is lossy sourced?
I mean, sometimes it's easy, I check the vobs with Gspot and it reports a lower video resolution than dvd standards. Other times a dvd may look lossy sourced but Gspot reports an ok resolution (so it may have been reencoded from divx to dvd). Is there a way to detect if this kind of dvds are actually lossy sourced?
Thanks in advance for your help.
Reply With Quote Reply with Nested Quotes
  #2  
Old 2010-01-19, 06:53 AM
Thulani's Avatar
Thulani Thulani is offline
172.31 GB/208.97 GB/1.21
 
Join Date: Jul 2005
Location: Romania
Re: How to detect lossy sourced dvds

A lower resolution doesn't mean a 'lossy' sourced (mpeg2 is also lossy). Some TV station broadcast in different resolutions.

Most reencoders leave artifacts behind (depixelation) so you need to watch for those things.
Reply With Quote Reply with Nested Quotes
  #3  
Old 2010-01-19, 10:31 AM
showtaper's Avatar
showtaper showtaper is offline
304.10 GB/469.31 GB/1.54
 
Join Date: Jul 2005
Re: How to detect lossy sourced dvds

The DVD standard allows a pretty wide variance in quality. From the DVD Video wikipedia entry:

========================================================

To record moving pictures DVD-Video utilizes either MPEG-2 compression at up to 9.8 Mbit/s (9800 kbit/s) or MPEG-1 compression at up to 1.856 Mbit/s (1856 kbit/s).

The following formats are allowed for MPEG-2 video:

* At 25 frame/s (used in regions with 50 Hz image scanning frequency):

720 576 pixels MPEG-2 (Called full D1)
704 576 pixels MPEG-2
352 576 pixels MPEG-2 (Called Half-D1, same as the China Video Disc standard)

* At 29.97 or 23.976 frame/s (used in regions with 60 Hz image scanning frequency):

720 480 pixels MPEG-2 (Called full D1)
704 480 pixels MPEG-2
352 480 pixels MPEG-2 (Called Half-D1, same as the China Video Disc standard)

The following formats are allowed for MPEG-1 video:

* 352 288 pixels MPEG-1 at 25 frame/s (Same as the VCD Standard)
* 352 240 pixels MPEG-1 at 29.97 frame/s (Same as the VCD Standard)

Because of MPEG-1 constraints, interlacing is supported for MPEG-2 video only. All resolutions support video with 4:3 frame aspect ratio. Only formats with 720 pixels per scan line support widescreen video.

========================================================
Reply With Quote Reply with Nested Quotes
Reply

The Traders' Den > Where we go to learn ..... > Technobabble

Similar Threads
Thread Forum Replies Last Post
Is there a way to determine whether a video is lossy .mpg sourced? - Salva Veritate Lossy or Lossless? 8 2008-05-05 04:16 PM
Lossy Digital-sourced radio sample? - GRC Lossy or Lossless? 5 2007-07-20 03:03 PM
Is this lossy sourced? - Andy L Lossy or Lossless? 6 2007-07-16 10:55 PM
Is this recording lossy sourced? - liveman Lossy or Lossless? 4 2006-04-25 07:43 PM
lossy-sourced or not? - pandora18 Lossy or Lossless? 9 2005-05-04 12:55 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forums


All times are GMT -5. The time now is 08:29 AM.


Powered by: vBulletin, Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright ©2004 - , TheTradersDen.org - All Rights Reserved - Hosted at QuickPacket
no new posts