armadillo22
31st October 2008, 14:57
I've encountered an odd issue when encoding h264 quicktimes.
I'm using quicktime pro and am rendering out a .mov (video = h264, audio = aac).
I need to restrict the bitrates to specific values. Within the Videos settings I hit 'restrict to' and enter my values. (I'm creating 3 versions, 1 @ 960kbps, 1 @ 512kbps, and 1 @ 255kbps. All clips all have audio set to 64kbps AAC (Quality = Best, Encoding Stragey = CBR)
However everytime Quicktime now fails to respect these values. The bitrates for the video fluctuates usually between 10-30kbps above the set value, and Quicktime will disregard the audio settings and encode the audio at 128kbps.
Is this a known issue?
I've tried to create these quicktimes a number of ways using the following software:
Quicktime Pro (multiple builds including the latest) = Bitrates greater than specified
Pro Coder 3 = Bitrates greater than specified
Compressor = Encoded 960kbps version fine. Other 2 had bitrates greater than that specified.
Episode = Video bitrates came in under the value specified
No matter what I can not get quicktime to respect these bitrates.
But this is what puzzles me. Not a few weeks ago I did the same thing (on the same machine and Quicktime Pro) and no problems. I've even got the files, I've checked them and they appear to respect the bitrates fine.
Now...is it that actually encoded bitrates varied by such a margin (the 10-30kbps mentioned above) in the past but that Quicktime simply displayed the specified value (rather than the actual values) in the properties box, but recently thats been changed? If not and Quicktime isn't actually respecting specified values then isn't this a MAJOR issue? But my research has not lead me to others with similar issues.
Anyone else come across this sort of issue?
Any light you can shed on this would be greatly appreciated.
Regards
-A
I'm using quicktime pro and am rendering out a .mov (video = h264, audio = aac).
I need to restrict the bitrates to specific values. Within the Videos settings I hit 'restrict to' and enter my values. (I'm creating 3 versions, 1 @ 960kbps, 1 @ 512kbps, and 1 @ 255kbps. All clips all have audio set to 64kbps AAC (Quality = Best, Encoding Stragey = CBR)
However everytime Quicktime now fails to respect these values. The bitrates for the video fluctuates usually between 10-30kbps above the set value, and Quicktime will disregard the audio settings and encode the audio at 128kbps.
Is this a known issue?
I've tried to create these quicktimes a number of ways using the following software:
Quicktime Pro (multiple builds including the latest) = Bitrates greater than specified
Pro Coder 3 = Bitrates greater than specified
Compressor = Encoded 960kbps version fine. Other 2 had bitrates greater than that specified.
Episode = Video bitrates came in under the value specified
No matter what I can not get quicktime to respect these bitrates.
But this is what puzzles me. Not a few weeks ago I did the same thing (on the same machine and Quicktime Pro) and no problems. I've even got the files, I've checked them and they appear to respect the bitrates fine.
Now...is it that actually encoded bitrates varied by such a margin (the 10-30kbps mentioned above) in the past but that Quicktime simply displayed the specified value (rather than the actual values) in the properties box, but recently thats been changed? If not and Quicktime isn't actually respecting specified values then isn't this a MAJOR issue? But my research has not lead me to others with similar issues.
Anyone else come across this sort of issue?
Any light you can shed on this would be greatly appreciated.
Regards
-A