5MB/s?? at DVinfo.net

Go Back   DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon EOS Crop Sensor for HD

Canon EOS Crop Sensor for HD
APS-C sensor cameras including the 80D, 70D, 7D Mk. II, 7D, EOS M and Rebel models for HD video recording.


Reply
 
Thread Tools Search this Thread
Old December 27th, 2009, 01:49 PM   #1
Regular Crew
 
Join Date: May 2009
Location: Saly Hungary
Posts: 169
5MB/s??

I do not understand the specs of the 7D. After all the positive info on image quality of 7D video, I cannot beleive the bitrate of 5 MB/s in the specs on Dpreview. What does this mean? It is much lower then most camcorders. Worse image quality?
Rob deJong is offline   Reply With Quote
Old December 27th, 2009, 01:52 PM   #2
Inner Circle
 
Join Date: Nov 2006
Location: Tallahassee, FL
Posts: 4,100
Umm, common mistake.

The "B" is capitalized. 5MBps = 40Mbps. Usually you see the Mbps listed for camcorders.
__________________
DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.
Perrone Ford is offline   Reply With Quote
Old December 27th, 2009, 03:39 PM   #3
Regular Crew
 
Join Date: Mar 2004
Location: San Diego, California
Posts: 119
Yep - it's easy to forget the bytes/bits thing...
__________________
Mark Holmes
www.daisy3pictures.com
Mark Holmes is offline   Reply With Quote
Old December 27th, 2009, 05:12 PM   #4
Major Player
 
Join Date: Jan 2007
Location: Rockledge, Florida
Posts: 351
Yup....confusing. As much as I already know this I still get caught up in the confusion every now and then.
Ian G. Thompson is offline   Reply With Quote
Old December 27th, 2009, 08:21 PM   #5
Regular Crew
 
Join Date: May 2007
Location: Boston MA
Posts: 167
Quicktime inspector shows 48 mbits/s for the original 7D 1080/30p clips.
Pedanes Bol is offline   Reply With Quote
Old December 27th, 2009, 08:32 PM   #6
Major Player
 
Join Date: Jan 2007
Location: Rockledge, Florida
Posts: 351
Yup...that 48 megabits/s equals around 5.5 MB/s.
Ian G. Thompson is offline   Reply With Quote
Old December 28th, 2009, 12:20 PM   #7
Major Player
 
Join Date: Nov 2006
Location: Brisbane, California
Posts: 530
Has anybody seen any codec related motion artifacts at this pretty high bitrate and theoretically good codec? I haven't noticed but I haven't been looking hard.
Keith Moreau is offline   Reply With Quote
Old December 28th, 2009, 12:32 PM   #8
Inner Circle
 
Join Date: Nov 2006
Location: Tallahassee, FL
Posts: 4,100
Quote:
Originally Posted by Keith Moreau View Post
Has anybody seen any codec related motion artifacts at this pretty high bitrate and theoretically good codec? I haven't noticed but I haven't been looking hard.
Many. And I've posted some here.
__________________
DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.
Perrone Ford is offline   Reply With Quote
Old December 28th, 2009, 12:43 PM   #9
Major Player
 
Join Date: Sep 2006
Location: London, England
Posts: 969
Quote:
Originally Posted by Keith Moreau View Post
Has anybody seen any codec related motion artifacts at this pretty high bitrate and theoretically good codec? I haven't noticed but I haven't been looking hard.
Loads. Some shots have been totally unusable due to the failings of the codec. But at least I know what to avoid now:)
__________________
Writer-Director-DOP
www.liamhall.net
Liam Hall is offline   Reply With Quote
Old January 1st, 2010, 01:20 PM   #10
Regular Crew
 
Join Date: Oct 2009
Location: Turku, Finland
Posts: 30
Quote:
Originally Posted by Liam Hall View Post
Loads. Some shots have been totally unusable due to the failings of the codec. But at least I know what to avoid now:)
Could you send some examples, please.

Kind regards,
jan
__________________
The Forgiveness A Film About Life
Jan Tervo is offline   Reply With Quote
Old January 2nd, 2010, 04:48 PM   #11
Barry Wan Kenobi
 
Join Date: Jul 2003
Location: North Carolina
Posts: 3,863
Quote:
Originally Posted by Keith Moreau View Post
Has anybody seen any codec related motion artifacts at this pretty high bitrate and theoretically good codec? I haven't noticed but I haven't been looking hard.
Understand that while the bitrate is pretty high, and the codec is theoretically good, the particular implementation of the codec is simplistic, so the overall performance isn't nearly as good as you'd expect. Not all implementations of h.264 are equivalent. There are certain features or tools that the designers can choose to use or not use. On the 5D/7D, they chose not to use B-frames, and B-frames give the codec incredible efficiency. As a net result, 50mbps of h.264 on the 5D/7D isn't nearly as robust as the 21mbps PH mode of AVCHD h.264 is.

So -- to sum it up, the codec in the 7D is pretty good, but as for codec artifacting, it's probably only about HDV caliber when all is said and done.
Barry Green is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon EOS Crop Sensor for HD

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 09:16 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network