compression noise in editing.. best method? at DVinfo.net

Alex Humphrey · August 10th, 2007, 12:51 PM

Hello, I'm running a JVC HD110 720p at 30fps and capturing and editing on a mac platform FCP (studio 1) capturing HDV, edit native. I just picked up a 23" Samsung LCD HDTV and using that as a preview monitor. I see a fair amount of compression noise in medium tones where there is little variation in tone or color. Is this just HDV, or possibly is it better to change my capture settings? Capturing HDV but letting it expand into a less compressed format before dropping it into the hard drive? Going from that to SD DVD the noise becomes very apparant. I experimented with exporting the HDV out to DVC PRO-HD then into DVD Studio Pro as well as Quicktime files, and both were significantly better final results than just going out native HDV. I'm betting its best to get away from HDV in editing ASAP and edit in a less lossy format.

thanks
alex

Scott Jaco · August 10th, 2007, 02:35 PM

Quote:

Originally Posted by Alex Humphrey

Hello, I'm running a JVC HD110 720p at 30fps and capturing and editing on a mac platform FCP (studio 1) capturing HDV, edit native. I just picked up a 23" Samsung LCD HDTV and using that as a preview monitor. I see a fair amount of compression noise in medium tones where there is little variation in tone or color. Is this just HDV, or possibly is it better to change my capture settings? Capturing HDV but letting it expand into a less compressed format before dropping it into the hard drive? Going from that to SD DVD the noise becomes very apparant. I experimented with exporting the HDV out to DVC PRO-HD then into DVD Studio Pro as well as Quicktime files, and both were significantly better final results than just going out native HDV. I'm betting its best to get away from HDV in editing ASAP and edit in a less lossy format.

thanks
alex

You can try AIC 720/30. It gets rid of the GOP for faster editing & rendering. I've done frame based comparisons and I see no gain or loss with picture quality when using AIC. It looks exactly the same but HDV does have slight compression artifacts in the darker shadowed out areas of the frame if you look closely. It's a 19.2Mbps stream so you can't expect it to compete with DVCPro HD.

The benefit is obvious. I use $3 tapes. Others use $1,500 P2 cards.

Jonathan Nelson · August 11th, 2007, 02:51 AM

Well, what you see is what you get. A compressed format cannot all the sudden revive it's self by using a heavier codec such as DVC PRO HD.

It's like trying to turn a timex to a gucci by putting the timex in a gucci box (or something like that).

LCD monitors always show lots of noise but my advice is to soften the image a bit using a blur and maybe lower the contrast.

AIC isnt a bad idea though. It is not as cpu intensive and I seriously see no difference in picture.

Also, DVC PRO-HD is 960x720 so you lose some resolution. I would stay away from that codec.

Adriano Apefos · August 11th, 2007, 03:31 AM

I think I found a way to minimize blocking artifacts in HDV blacks. I would like to explain and if someone try it, let me know.

1 - put the same m2t footage aligned in two video tracks in Adobe Premiere.

2 - in the upper track apply gaussian blur and adjust between 4 and 6. (adjust looking the blacks)

3 - in the upper track apply arbitrary map and adjust between -5 and -1 (adjust looking the blacks)

4 - in the upper track apply luminance key (adjust the key to keep only the blacks of the upper track over the lower track, be carefull to not get color fringing in key edges)

5 - render to uncompressed.

The goal is to minimize the blocking artifacts in the blacks where HDV compression is more visible.

If someone try this, let me know.

Thanks.

August 10th, 2007, 12:51 PM	#1
Alex Humphrey Major Player Join Date: Mar 2007 Location: california North and South Posts: 642	compression noise in editing.. best method? Hello, I'm running a JVC HD110 720p at 30fps and capturing and editing on a mac platform FCP (studio 1) capturing HDV, edit native. I just picked up a 23" Samsung LCD HDTV and using that as a preview monitor. I see a fair amount of compression noise in medium tones where there is little variation in tone or color. Is this just HDV, or possibly is it better to change my capture settings? Capturing HDV but letting it expand into a less compressed format before dropping it into the hard drive? Going from that to SD DVD the noise becomes very apparant. I experimented with exporting the HDV out to DVC PRO-HD then into DVD Studio Pro as well as Quicktime files, and both were significantly better final results than just going out native HDV. I'm betting its best to get away from HDV in editing ASAP and edit in a less lossy format. thanks alex

August 11th, 2007, 02:51 AM	#3
Jonathan Nelson Major Player Join Date: Apr 2006 Location: Kingman Arizona Posts: 298	Well, what you see is what you get. A compressed format cannot all the sudden revive it's self by using a heavier codec such as DVC PRO HD. It's like trying to turn a timex to a gucci by putting the timex in a gucci box (or something like that). LCD monitors always show lots of noise but my advice is to soften the image a bit using a blur and maybe lower the contrast. AIC isnt a bad idea though. It is not as cpu intensive and I seriously see no difference in picture. Also, DVC PRO-HD is 960x720 so you lose some resolution. I would stay away from that codec. __________________ Florescent tungsten hovered under cubicle design

August 11th, 2007, 03:31 AM	#4
Adriano Apefos Regular Crew Join Date: Jun 2007 Location: Belo Horizonte BRAZIL Posts: 154	HDV blocking artifacts minimization I think I found a way to minimize blocking artifacts in HDV blacks. I would like to explain and if someone try it, let me know. 1 - put the same m2t footage aligned in two video tracks in Adobe Premiere. 2 - in the upper track apply gaussian blur and adjust between 4 and 6. (adjust looking the blacks) 3 - in the upper track apply arbitrary map and adjust between -5 and -1 (adjust looking the blacks) 4 - in the upper track apply luminance key (adjust the key to keep only the blacks of the upper track over the lower track, be carefull to not get color fringing in key edges) 5 - render to uncompressed. The goal is to minimize the blocking artifacts in the blacks where HDV compression is more visible. If someone try this, let me know. Thanks.