16-235 Confusion

Perrone Ford · October 23rd, 2009, 08:41 AM

Are your project settings still 8-bit with 2.22 gamma? I think you are beginning to understand why I use linear gamma. Values below zero are B-L-A-C-K. Always.

And yes, there is a filter you can use to clip. It's is "Sony Broadcast Color" and use the "Extremely Conservative" setting.

Chris Gotzinger · October 23rd, 2009, 09:56 AM

Okay, I'll try that filter, thanks.
I haven't changed my bit depth and my gamma at all because I have several hundred clips on my timeline, all of which are graded individually. I will NOT redo this.

You know what's interesting. I loaded the video file into Virtualdub, and guess what - it doesn't look washed out the way it does in all the media players I've tried. I used "Copy source frame to clipboard" to check it out in Photoshop, and the values are good. I get blacks and whites exactly the way I want.

So I'm now thinking that for some reason those other media players don't do a conversion from 16-235 to 0-255.

Chris Gotzinger · October 23rd, 2009, 10:08 AM

I was right! I just played the file in Media Player Classic and checked out the properties of the decoding filter that was used, "MPV Decoder":
There is a "TV->PC" button, and once I pressed it the video played back with correct black and white levels, going from washed out to looking the way I want.

This leads me to believe that the video will play correctly on a Blu-ray hardware player.

Perrone Ford · October 23rd, 2009, 10:11 AM

Quote:

So I'm now thinking that for some reason those other media players don't do a conversion from 16-235 to 0-255.

And why should they? Again, this goes back to what a player EXPECTS. If you have a player expecting a TV level signal (16-235) it will set 16 to BLACK and 235 to WHITE. Anything outside of those numbers is clipped. If the player EXPECTS 0-255 and you GIVE it 16-235, it's going to look washed out.

Your computer monitor is EXPECTING 0-255, but your video signal from the NLE is giving it 16-235 which is legal for broadcast. It only looks right on your monitor when you input illegal values which push the signal closer to 0-255.

A DVD player or TV *expects* 16-235 and it does NOT expect anything outside those boundaries. So when you create your mpeg2 or AVC for DVD or BluRay, it's going to encode to 16-235. That is PURE BLACK on TV and PURE WHITE.

Does this make sense?

Chris Gotzinger · October 23rd, 2009, 10:39 AM

It makes perfect sense now indeed. Awesome!

Anton Strauss · October 23rd, 2009, 06:34 PM

I am not familiar with Vegas but it is simple in Edius

simlpy tick "safe color" and all below 0 and above 100 is clipped
http://www.videoproductions.com.au/e...safe-color.avi (7mb)

and if you don't want clipping, then apply YUV curve filter and adjust

October 23rd, 2009, 08:41 AM	#16
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	Are your project settings still 8-bit with 2.22 gamma? I think you are beginning to understand why I use linear gamma. Values below zero are B-L-A-C-K. Always. And yes, there is a filter you can use to clip. It's is "Sony Broadcast Color" and use the "Extremely Conservative" setting. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

October 23rd, 2009, 06:34 PM	#21
Anton Strauss Major Player Join Date: Sep 2009 Location: Sydney, Australia Posts: 201	I am not familiar with Vegas but it is simple in Edius simlpy tick "safe color" and all below 0 and above 100 is clipped http://www.videoproductions.com.au/e...safe-color.avi (7mb) and if you don't want clipping, then apply YUV curve filter and adjust __________________ Anton Strauss www.videoproductions.com.au

October 23rd, 2009, 09:56 AM	#17
Chris Gotzinger Regular Crew Join Date: Mar 2009 Location: Dusseldorf Posts: 32	Okay, I'll try that filter, thanks. I haven't changed my bit depth and my gamma at all because I have several hundred clips on my timeline, all of which are graded individually. I will NOT redo this. You know what's interesting. I loaded the video file into Virtualdub, and guess what - it doesn't look washed out the way it does in all the media players I've tried. I used "Copy source frame to clipboard" to check it out in Photoshop, and the values are good. I get blacks and whites exactly the way I want. So I'm now thinking that for some reason those other media players don't do a conversion from 16-235 to 0-255.

October 23rd, 2009, 10:08 AM	#18
Chris Gotzinger Regular Crew Join Date: Mar 2009 Location: Dusseldorf Posts: 32	I was right! I just played the file in Media Player Classic and checked out the properties of the decoding filter that was used, "MPV Decoder": There is a "TV->PC" button, and once I pressed it the video played back with correct black and white levels, going from washed out to looking the way I want. This leads me to believe that the video will play correctly on a Blu-ray hardware player.

October 23rd, 2009, 10:39 AM	#20
Chris Gotzinger Regular Crew Join Date: Mar 2009 Location: Dusseldorf Posts: 32	It makes perfect sense now indeed. Awesome!