-
Bitrate settings doesn´t work
When I tell Compressor to use bitrate of 35 mbps it becomes 21 mbps.
Have been testing bitrates between 18 and 50 and it always turns out to be much smaller.
How come?
Sverker Hahn, Stockholm
Slower is better!
Sony EX1
Final Cut Studio 2
iMac Intel
MacBook Pro 15″ -
5 Replies
-
Not nearly enough information. Without telling us specifics such as the codec you’re starting with and the codec you’re encoding to, no one here can do anything but guess how to help you. BTW, some codecs have locked-in bitrates, for example DV is 25mbps, and you can try increasing the nitrate all you want, but it dies nothing.
David Roth Weiss
Director/Editor/Colorist
David Weiss Productions, Inc.
Los Angeles
https://www.drwfilms.comPOST-PRODUCTION WITHOUT THE USUAL INSANITY ™
A forum host of Creative COW’s Business & Marketing and Apple Final Cut Pro forums. Formerly host of the Apple Final Cut Basics, Indie Film & Documentary, and Film History & Appreciations forums.
-
Ooops – of course! Sorry about that.
Starting with XDCAM EX 35 mbps.
Settings in Compressor:
File Extension: mov
Estimated file size: 21.46 GB/hour of source
Audio Encoder
AAC, Stereo (L R), 44,100 kHz
Video Encoder
Format: QT
Width: 1920
Height: 1080
Pixel aspect ratio: Square
Crop: None
Padding: None
Frame rate: (100% of source)
Frame Controls: Automatically selected: Off
Codec Type: H.264
Multi-pass: On, frame reorder: Off
Pixel depth: 24
Spatial quality: 75
Min. Spatial quality: 25
Key frame interval: 5
Temporal quality: 50
Min. temporal quality: 25
Average data rate: 51.2 (Mbps)
Maximum data rate: 51.2 (Mbps)
Fast Start: onThe file is 1.09 GB with a duration of 9 min 22 sec and a bitrate of 16.65 Mbits/s according to Quicktime Player 7.6.4.
Compressor 3.0.5.
I do not understand some of the above, eg what the key frame interval means – at least I have not seen any difference in footage quality between 5 and 25.
Sverker Hahn, Stockholm
Slower is better!
Sony EX1
Final Cut Studio 2
iMac Intel
MacBook Pro 15″ -
Sorry, I have got my footage mixed up.
Now it seems there is not such a big difference as above.
Instead of 50 Mbps I get 46.
I think that my post was not a good one …
Thanks anyway, David!
Sverker Hahn, Stockholm
Slower is better!
Sony EX1
Final Cut Studio 2
iMac Intel
MacBook Pro 15″ -
[Sverker Hahn] “Frame Controls: Automatically selected: Off”
Set it ON.[Sverker Hahn] “Key frame interval: 5”
Set it AUTO[Sverker Hahn] “Average data rate: 51.2 (Mbps)
Maximum data rate: 51.2 (Mbps)”
This dat-rate makes no much sense. Is HUGE.
rafael -
You must be using variable bit rate as you have multi pass on. Therefore the file will go up to the maximum you have set only when it needs to do complex scenes. You are seeing the average.
If you want to lock in a high bit rate, you need Constant Bit rate (CBR not VBR), although as Rafael has said, your bit rate is very high.
Reply to this Discussion! Login or Sign Up