#1  
06-06-2015, 07:22 AM
rocko's Avatar
rocko rocko is offline
Premium Member
 
Join Date: Oct 2010
Posts: 463
Thanked 14 Times in 14 Posts
Got Stumped on:"Max" Bit-rate versus "Target" Bit-rate settings ..a little confused ....I am setting up several MPEG-2 pre-sets and some will be "Broadcast" @ 20MB/S (A happy medium between going .MPEG2 vs .AVI ?)..Then 15MB/S, Then 10MB/S and so fourth...To Make several pre-sets and then Run thru them from the same tape footage..My Question is do I focus on "Max" or "Target" Bit rate setting?.
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Ads / Sponsors
 
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
06-12-2015, 08:09 AM
sanlyn sanlyn is offline
Premium Member
 
Join Date: Aug 2009
Location: N. Carolina and NY, USA
Posts: 3,648
Thanked 1,307 Times in 982 Posts
What does "Broadcast" mean?

The maximum bitrate for MPEG2 for DVD is 9000 kbps. If you are using VBR encoding, the max bitrate is the highest value you want the encoder to use. The "target" bitrate is the average target that you want for your encode and must be lower than the max bitrate. With standard definition MPEG2, anything over 8000 or 9000 will give no added benefit. If you want more bitrate, you're better off with a BluRay/AVCHD encoder. The max bitrate for BluRay MPEG2 encoding is 15MBps.

You should give more detail about your source video and what your intended output is for.
Reply With Quote
The following users thank sanlyn for this useful post: rocko (06-14-2015)
  #3  
06-13-2015, 05:53 PM
lordsmurf's Avatar
lordsmurf lordsmurf is online now
Site Staff | Video
 
Join Date: Dec 2002
Posts: 13,508
Thanked 2,449 Times in 2,081 Posts
Target/Max is a VBR setting. Target is what you want for average. Max is max allowed. For example, for 352x480 DVD, a good average is 3.5mbps with a 4.5mbps max. The VBR knows to try to use 3.5 as much as possible, but can go up to 4.5 on tough scenes, and down to almost 0 when not needed.

Broadcast spec MPEG-2 is anywhere from 10mbps to 50mbps, with most falling in the 20s range. I used to refer to 15mbps as "broadcast spec" myself, but began to refer to 15mbps as "blu-ray spec" (which it is) and anything over 15 to be "broadcast". 10 is the DVD max, but there's really no needed to do anything in the 10-15 range, and almost nobody does.

I use 15mbps MPEG-2 myself, and have for several years now. The quality is better than DVD and the original tapes, and unlikely to ever get better. I only capture lossless when restoration is needed -- and then convert in MainConcept to 15mbps MPEG-2 when done. Mine is for TV watching, up to 60" HDTV. I couldn't care less about sharing on streaming sites.

- Did my advice help you? Then become a Premium Member and support this site.
- For sale in the marketplace: TBCs, workflows, capture cards, VCRs
Reply With Quote
The following users thank lordsmurf for this useful post: rocko (06-14-2015)
  #4  
06-14-2015, 04:24 AM
rocko's Avatar
rocko rocko is offline
Premium Member
 
Join Date: Oct 2010
Posts: 463
Thanked 14 Times in 14 Posts
Thank you both L.S. and Sanlyn, My source tapes are home-made, 1990's, Standard VHS, Consumer-grade Camera, of Diesel and Steam Railroad Action, All out-doors, with minimal panning and zooming. The most "Fast Action" comes from the Steam Engine's Drivers and Smoke, and then of course lots of Telephone poles and Rails...But the (Almost New!) Mitsubishi HD200U's TBC and AV Toolbox fixes most of those "wiggly" poles and rails....Iv'e been interested in highest possible MPEG2 bitrate setting for these tapes that are dear to me, without having to go AVI..(not much editing needed)..and use the more common bitrate setting for not-so-precious tapes. Here is a link to the nice chart that L.S. made a while ago http://www.digitalfaq.com/forum/vide...re-format.html

Last edited by rocko; 06-14-2015 at 04:39 AM. Reason: add
Reply With Quote
  #5  
06-14-2015, 11:38 AM
sanlyn sanlyn is offline
Premium Member
 
Join Date: Aug 2009
Location: N. Carolina and NY, USA
Posts: 3,648
Thanked 1,307 Times in 982 Posts
Then use the broadcast MPEG2 suggested bitrates if you wish, but remember that 20MBps is the max. You can save space using 2-pass VBR with 20MBps as the mac and about 10 or 12MBps as your target -- 2-pass VBR encoding will use the bitrate that the encoder feels is necessary as it goes along. Encoding at constant bitrate (CBR) would use the MAX setting all the time, which will waste a lot of databits where they aren't needed.

Also note that broadcast MPEG2 is not DVD compatible. If you want DVD for final delivery or an h264 format like standard def BluRay or AVCHD, all three must be re-encoded properly for those formats.

Not sure what you mean by "a little editing". Any cropping, color correction, transitions, or other image mods will be re-encoded, regardless of the output codec. For simple cut-and-join edits, many budget or free MPEG editors might not be able to accept the broadcast bitrate, and will cut only on I-frames or full GOPs anyway. Some smart-rendering MPEG editors that can make frame-specific cuts by re-encoding only the immediate GOP's in the cut region might inform you beforehand that the bitrate is not DVD compatible, if DVD output is what you want.

I agree with lordsmurf who implied that capturing interlaced source as non-interlaced is a big step removed from a true archive. The quality depends on the interlaced method used, which is usually inferior to several good deinterlacers available today. If you have an archive that's closer to the original source, you can change it with a working copy however you like afterwards. If you make those changes during capture you're stuck with them, period.
Reply With Quote
The following users thank sanlyn for this useful post: lordsmurf (06-20-2015), rocko (06-14-2015)
  #6  
06-20-2015, 08:24 AM
lordsmurf's Avatar
lordsmurf lordsmurf is online now
Site Staff | Video
 
Join Date: Dec 2002
Posts: 13,508
Thanked 2,449 Times in 2,081 Posts
MBps would be "megabytes per second". It's actually "mbps", which is "megabits per second".

We're all guilty of using the wrong Mb/MB/mb.

- Did my advice help you? Then become a Premium Member and support this site.
- For sale in the marketplace: TBCs, workflows, capture cards, VCRs
Reply With Quote
The following users thank lordsmurf for this useful post: rocko (06-20-2015)
  #7  
06-20-2015, 01:13 PM
rocko's Avatar
rocko rocko is offline
Premium Member
 
Join Date: Oct 2010
Posts: 463
Thanked 14 Times in 14 Posts
Quote:
Originally Posted by sanlyn View Post
Then use the broadcast MPEG2 suggested bitrates if you wish, but remember that 20MBps is the max. You can save space using 2-pass VBR with 20MBps as the mac and about 10 or 12MBps as your target -- 2-pass VBR encoding will use the bitrate that the encoder feels is necessary as it goes along. Encoding at constant bitrate (CBR) would use the MAX setting all the time, which will waste a lot of databits where they aren't needed.

Also note that broadcast MPEG2 is not DVD compatible. If you want DVD for final delivery or an h264 format like standard def BluRay or AVCHD, all three must be re-encoded properly for those formats.

Not sure what you mean by "a little editing". Any cropping, color correction, transitions, or other image mods will be re-encoded, regardless of the output codec. For simple cut-and-join edits, many budget or free MPEG editors might not be able to accept the broadcast bitrate, and will cut only on I-frames or full GOPs anyway. Some smart-rendering MPEG editors that can make frame-specific cuts by re-encoding only the immediate GOP's in the cut region might inform you beforehand that the bitrate is not DVD compatible, if DVD output is what you want.

I agree with lordsmurf who implied that capturing interlaced source as non-interlaced is a big step removed from a true archive. The quality depends on the interlaced method used, which is usually inferior to several good deinterlacers available today. If you have an archive that's closer to the original source, you can change it with a working copy however you like afterwards. If you make those changes during capture you're stuck with them, period.
Thanks Sanlyn, Once again looks like I have some deciding to do...Mainly Capture for Master file,(.avi probably) then can encode for DVD or/and Video website sharing..Thanks for pointing this out, especially the high bitrate not being compatable for DVD!..I tried to make a dvd ready file in MPEG video wizard with 15mpb/s file, and the DVD kept freezing on playback.
Reply With Quote
  #8  
06-20-2015, 01:16 PM
rocko's Avatar
rocko rocko is offline
Premium Member
 
Join Date: Oct 2010
Posts: 463
Thanked 14 Times in 14 Posts
Quote:
Originally Posted by lordsmurf View Post
MBps would be "megabytes per second". It's actually "mbps", which is "megabits per second".

We're all guilty of using the wrong Mb/MB/mb.
Thanks Lordsmurf, I was wondering if that was the case...you take the bit road,and I'll take the byte road!
Reply With Quote
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
Womble MPEG Video Wizard DVD on Win 7 not showing toolbar? rocko Edit Video, Audio 7 09-14-2012 10:30 AM
ATI All In Wonder card TV wizard locks up and shuts off pbd2012 Capture, Record, Transfer 5 04-01-2012 08:51 AM
Womble; MPEG VCR vs Easy DVD vs WIZARD 5.0 rocko Edit Video, Audio 2 10-02-2011 03:13 PM

Thread Tools



 
All times are GMT -5. The time now is 03:59 AM