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Bruce Phung · December 30th, 2009, 08:32 PM

I read a post some where saying when you import AVCHD into the timeline and make your edit, you will find AVCHD quality degraded, any truth to this.. Also, what is the best way to preserve edited HD file? Any inputs is appreciated.

Robert M Wright · December 30th, 2009, 09:00 PM

If you edit an AVCHD file, and encode the result as AVCHD (H264 compression), of course there will be image degradation (from the re-compression).

A lot of folks use Cineform as a visually lossless intermediate codec for editing. It's a pretty elegant intermediate codec. You could use it to save a visually lossless copy of your edited work as well.

Bruce Phung · December 30th, 2009, 09:22 PM

After I edit the footage, apply fx, transition etc, render out with Sony AVC template 1440 x 1080, there no recompression required. I guess my question is more about editing the avchd file can cause degrade in quality?

ps. I will definately want to get Cineform later on.

Robert M Wright · December 30th, 2009, 09:34 PM

Quote:

Originally Posted by Bruce Phung

...render out with Sony AVC template 1440 x 1080...

Aka AVCHD compression (which is lossy compression).

Eugenia Loli-Queru · December 31st, 2009, 03:21 AM

No, there is no degradation in quality in the timeline.

However, you mention that no recompression is required after you added FX, which is not true. In that case, it will have to re-compress.

Jim Snow · December 31st, 2009, 11:27 AM

While your footage is on the timeline, FX and any other editing changes do not affect your original file. These changes are only applied to a new output file when you render your project. Your original video file is untouched. Since the changes you made are then applied to your footage when you render your project, there is a loss that occurs when the rendering is done to the output video file because it is being recompressed as well.

The benefit of a lossless (or near lossless) format is that you can include more than one reencoding pass in your work flow without significant damage to your video. If you are simply loading your AVCHD footage, editing and then rendering your final output, there is no need to convert to a lossless format except for possible compatibility problems with your editor and performance concerns because AVCHD is more of a "load" on your processor.

Robert M Wright · December 31st, 2009, 12:27 PM

Btw, don't save your "render" using the same file name as the original source footage.

December 30th, 2009, 08:32 PM	#1
Bruce Phung Major Player Join Date: Dec 2009 Location: Rochester,NY USA Posts: 285	Avchd I read a post some where saying when you import AVCHD into the timeline and make your edit, you will find AVCHD quality degraded, any truth to this.. Also, what is the best way to preserve edited HD file? Any inputs is appreciated.

December 30th, 2009, 09:00 PM	#2
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	If you edit an AVCHD file, and encode the result as AVCHD (H264 compression), of course there will be image degradation (from the re-compression). A lot of folks use Cineform as a visually lossless intermediate codec for editing. It's a pretty elegant intermediate codec. You could use it to save a visually lossless copy of your edited work as well.

December 30th, 2009, 09:22 PM	#3
Bruce Phung Major Player Join Date: Dec 2009 Location: Rochester,NY USA Posts: 285	After I edit the footage, apply fx, transition etc, render out with Sony AVC template 1440 x 1080, there no recompression required. I guess my question is more about editing the avchd file can cause degrade in quality? ps. I will definately want to get Cineform later on.

December 31st, 2009, 03:21 AM	#5
Eugenia Loli-Queru Major Player Join Date: Jun 2007 Location: Bay Area, CA, USA Posts: 348	No, there is no degradation in quality in the timeline. However, you mention that no recompression is required after you added FX, which is not true. In that case, it will have to re-compress.

December 31st, 2009, 11:27 AM	#6
Jim Snow Trustee Join Date: Mar 2009 Location: Santa Clara, CA Posts: 1,104	While your footage is on the timeline, FX and any other editing changes do not affect your original file. These changes are only applied to a new output file when you render your project. Your original video file is untouched. Since the changes you made are then applied to your footage when you render your project, there is a loss that occurs when the rendering is done to the output video file because it is being recompressed as well. The benefit of a lossless (or near lossless) format is that you can include more than one reencoding pass in your work flow without significant damage to your video. If you are simply loading your AVCHD footage, editing and then rendering your final output, there is no need to convert to a lossless format except for possible compatibility problems with your editor and performance concerns because AVCHD is more of a "load" on your processor.

December 31st, 2009, 12:27 PM	#7
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Btw, don't save your "render" using the same file name as the original source footage.