anyone know the codec bandwidth both the 7D and 5D ?
- Thread starter doondoon
- Start date
Rakesh Jacob
Veteran
17mbps??? Where did you hear that?
5Dmkii 1080-30p about 38mbps
7D 1080-30p about 47mbps
5Dmkii 1080-30p about 38mbps
7D 1080-30p about 47mbps
Michael Olsen
Veteran
To make it even more clear:
(all measurements are approximate - always give some headroom)
5D MKII:
38 megabits per second
4.75 megabytes per second
7D:
47 megabits per second
5.9 megabytes per second
Rakesh Jacob
Veteran
yes thnx for dividing by 8 Michael LOL
Michael Olsen
Veteran
Its my only real skill.
But really, people tend to read mbps as both bits and bytes, leading to much undue worry.
Rakesh Jacob
Veteran
Its my only real skill.
But really, people tend to read mbps as both bits and bytes, leading to much undue worry.
you are absolutely right
EDIT: I mean about the bits vs Bytes, not the skills part
doondoon
Well-known member
I don't remember where. thanks for the info.
doondoon
Well-known member
Is this documented on the Canon website anywhere?
Rakesh Jacob
Veteran
Not sure, that info is from various testers looking at real world files
Also the T1i / 500D gets about 26-27mbps @ 720-30p from what I've personaly seen
@zeke 4:2:0
Also the T1i / 500D gets about 26-27mbps @ 720-30p from what I've personaly seen
@zeke 4:2:0
ryansheffer
Well-known member
My footage with my 5d is always between 38mbps and 41mbps.
My 1st day with the 7d has shown footage between 45mbps and 49mbps.
My 1st day with the 7d has shown footage between 45mbps and 49mbps.
doondoon
Well-known member
So the 7D not only uses a higher bitrate than the 5D, but because it's shooting less frames (24 vs 30 on the 5D) this should give us an additional 25% more bits dedicated to each image, right?
Would love to see a 7D & 5D side by side with the same heavy grade applied to them and see which one holds up better!
Would love to see a 7D & 5D side by side with the same heavy grade applied to them and see which one holds up better!
Barry_Green
Moderator
No, it doesn't really work that way. In an intraframe-only codec, yes you'd be right and it would be a big jump in quality. In a long-GoP codec, not necessarily.
There are fewer frames, yes, but a long-GoP codec compresses only the changes between frames. So with fewer frames per second, that means the changes between frames will be larger/more substantial, and therefore the codec has to work harder to compress those frames. With more frames per second the changes between frames will be smaller, making the codec not have to work so hard.
So -- it probably nets out to about the same thing, by the time it's done.
The bigger bandwidth will help, unquestionably (assuming that all other things are equal and they use the same type of h.264 encoding, same group size, etc). But the fewer frames per sec won't help as much as you might otherwise think.
Michael Olsen
Veteran
EDIT: Post self-deleted due to rampant stupidity. Sorry.
Last edited:
doondoon
Well-known member
Peter J. DeCrescenzo
Veteran
Refer to page 255 in the 7D user instruction manual:
http://www.usa.canon.com/consumer/c...ategoryid=139&modelid=19356#DownloadDetailAct
Divide "MB" (megabytes) by 8 to get megabits.
If you want just want average bitrate for a clip, you could use "bitrate viewer"
If you want more fancy analysis you can use other programs like elecard streameye or h264info
Very interesting, thanks Barry.