Question about encoding

[John Rofrano]

Whenever you transcode a file even to the same format there will be some quality loss but as Steve said, you probably won’t notice with just one transcode. It’s when you do it a couple of time that it starts to degrade.

People get very hung up with this but I mostly work with HDV and I regularly render out an intro or some complicated compositing out to HDV and drop it back in the project and no one can tell the difference.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[John Rofrano]

[nmou nmou] “Why is there just steve rhoden and John Rofrano who are responding ? Is this forum just for them O.o”

lol… I’ll give you a hint about this forum because it’s different than some of the other Creative COW forums. On the other forums, the pictures at the stop are the “official” moderators. On this forum, the pictures on top are the people who contribute the most. So Jeff, Mike, Stephen, Nigel, Roger, and Dave have all earned their spot up there in addition to Steve and I.

What happens is sometimes you’ll see us a lot and sometimes you’ll see us less because we have a looming project deadline so based on our workloads, there are always some of us that are active at any given point in time.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Jeff Schroeder]

Thanks for the vote of confidence, John. But, you know, all us little guys, we wanna be just like you and Steve!

(lol)

2-Xeon X5680 @ 3.33, EVGA SR-2 Mobo, 48GB DDR3, GTX 580 3072MB, 16TB Attached Storage, Win7, Vegas 11 x64

[Nmou Nmou]

I was searchin another thing also : is there a way in vegas to “multiplex” (muxing) files without encoding ?

[John Rofrano]

[nmou nmou] ” is there a way in vegas to “multiplex” (muxing) files without encoding ?”

Well… Yes and No. 😉

Yes for certain AVI and MPEG-2 formats, Vegas will “smart render” by simply copying the parts that haven’t been compositied.

No, for formats like AVCHD (H.264/MPEG4). Those always get re-encoded.

You can try a tool like tsMuxeR. It will cut and combine certain files (like Transport Streams). I use it for .TS files that I record from my Hauppauge HD PVR and it works great for cutting out commercials without loosing any quality.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Nmou Nmou]

I’m searching for a demuxing softare that works with all kind of file/formats 🙂

[Nmou Nmou]

Ok i was talking about reencoding a video with same codec but now, if i encode a video from a camera (dv for example) to mpeg4 avc there will be a difference ?

[John Rofrano]

[nmou nmou] “if i encode a video from a camera (dv for example) to mpeg4 avc there will be a difference ?”

Yes, there will be a difference but depending on the bit-rate that you use, you may not notice. As long as you have enough bits to encode all the details in the original video, they will be there and it will look fine.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Nmou Nmou]

Ok so now if i encode a camera video with same bitrate but different codec, there will be also same quality ?

[John Rofrano]

[nmou nmou] “Ok so now if i encode a camera video with same bitrate but different codec, there will be also same quality ?”

No, it depends. Different codecs give different quality at the same bit-rate. You cannot compare bit-rates between codecs. For example, 16Mbps MPEG4/AVC/H.264 is about the same “quality” as 25Mbps MPEG-2 because MPEG4 uses better encoding algorithms than MPEG2.

The same can be said for DV. A DV camera shoots 25Mbps (DV25) or 50Mpbs (DV50) but it looks fine when rendered to 8Mbps MPEG2 on a DVD because MPEG2 uses interframe compression which needs less bits that the intraframe compression used by the DV codec. So you can’t use bit-rate as a guide for quality across codecs.

~jr

http://www.johnrofrano.com
http://www.vasst.com