MP4 rendering too dark/wrong colors

[Graham Bernard]

That’s very helpful.

Jeremy your scopes are showing stretched levels:

Below 16 : Crushed Blacks

Above 235: Super Whites

I now always add the C-to-S RGB to get within those Levels.

We now need to ascertain, amongst all your expermeinets – which are very worthwhile indeed! – just where you’d need to slot it in.

My thoughts are that you are originally dealing with a Graphics format and now need to bring it, the video, into the video domain.

My “poor” understanding is that Graphics are in 0>255 doamin, where video is in the 16>>235 domain. Added to which Vegas deals with this in a non-intuitive way and needs to be understood correctly. For example any graphics I deal with I clobber with the CtoS RGB leveller!

HTHs

Grazie

Video Content Creator and Potter
PC 7 64-bit 16gb * Intel® Core™i7-2600k Quad Core 3.40GHz * 2GB NVIDIA GEFORCE GTX 560 Ti
Cameras: Canon XF300 + PowerShot SX50HS Bridge

[Jeremy Rodgers]

So my original footage has the wrong levels? I’m confused here. The scope I uploaded was from my raw video before rendering.

Don’t forget that I’m barely above amateur at this video editing stuff. All those numbers are like a foreign language to me.

I’ve applied both RGB filters and they didn’t fix it, they just changed it to a different color.

I’ll check into the preview differences after this rawcap finishes compiling, its slowing my hard drive down too much to mess with vegas.

[Jeremy Rodgers]

Alright so the video preview for the original footage in Sony Vegas looks exactly the same as the original footage. Perfect color. No darkness. Exact copy.

As for previewing in another player, I’m not sure how that would help, both videos are being viewed in the same player, so unless VLC displays video differently for each codec (one for raw video and one for mp4 compressed) then it wouldn’t make a difference.

Edit: I tried previewing both videos in another player just in case, the rendered video was darker there too. So it isn’t the player causing the problem.

Second edit: Here is a picture of the scope for my rendered video for comparison to the first one i posted of the original video.

Also, I dragged my rendered video into the timeline to compare it to the original in the vegas preview, it appears darker there too.

[Bill Burnette]

I’m having a look at differences between individual pixels of your screen shots. You can do this in photoshop by differencing two layers, then increasing the contrast of the result to visualize the difference.

Yes, the new one is slightly darker, and there is also a color shift toward blues and greens. Also, there does not seem to be a uniform stretching. Different pixels of the same color are converted to two or more different colors. Overall, it gives the impression of artifacts of recompression, which is always at the mercy of the particular software.

Another observation is that some of the lower-valued RGB components in the original are quantized. For example, whenever I see an ‘R’ component of 15 or less, it is either 15, 10, or 0, maybe because the whole image was computer-generated. Or it may indicate some stretching during the original production or quantizing during compression.

Also, all my observations could be completely invalid due to the jpg compression of the screen shots.

[Jeremy Rodgers]

Would it help to upload higher quality screenshots that haven’t been modified by imgur?

[Jeremy Rodgers]

I believe I made some improvements by using a new recording codec that records YUV420 instead of RGB.

It still isn’t exact color though. Im running out of ideas here.

Edit: Scratch that. Recording with anything other than RGB produces cloudy video that looks nothing like the original.

[Jeremy Rodgers]

So does anyone know if recording in RGB colorspace then rendering an MP4 as YUV could cause this color shift?

[Graham Bernard]

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[Jeremy Rodgers] “So does anyone know if recording in RGB colorspace then rendering an MP4 as YUV could cause this color shift?”
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You are into a whole World of Hurt!

OK, this is where I firmly don my World War I Soldier’s tin hat:

Ahem….. YUV was created by TV engineers to allow for RGB signals to be backward compatible for the imminent ’60s switch to full colour TVs and the need for the existing BnW TV deaspera, flange of BnW TV needing to be able to get the necessary greyscales from the new Colour Signals, and here’s the “thing”, without the need to have some really heavy weight hardware at EACH AND EVERY BnW TV in the land to be able to decode the newly to arrive colour signal. I think I got that right?

O…K…

Fast forward the tape by about 55 years, and here comes Jeremy, asking if there would be a mismatch in using a digital CODEC to retrieve the correct colour space via/from his MP4 journey through YUV. My stupid answer would be – “Well, why wouldn’t it shiver and tremble?”

As I’ve implied, this is waaaayyy above my pay-grade and would need a Glenn Chan to bug in here and either support or rip my understanding/theory to shreds.

OK, and in any case, Jeremy, now that you have your Waveform-Scopes-Head “on”, what are you deciding to do? I’ve invested not a little time I attempting to assist you and long to hear that you’ve got a way through.

Cheers

Grazie

Video Content Creator and Potter
PC 7 64-bit 16gb * Intel® Core™i7-2600k Quad Core 3.40GHz * 2GB NVIDIA GEFORCE GTX 560 Ti
Cameras: Canon XF300 + PowerShot SX50HS Bridge

[Jeremy Rodgers]

I don’t know if that reply was telling me it would cause my problem or wouldn’t. Entertaining nonetheless. That kind of stuff is beyond my knowledge.

To be honest I sort of gave up and attributed it to some sort of user error in my recording process. Since this issue is common with rendering an MP4 in vegas but not widespread it has to be something I’ve done wrong outside of vegas.

Either that or most people don’t notice the minor color shift. Which I doubt.

My video editing knowledge is too limited to correct the colors inside vegas, that would take entirely too much trial and error for me. There isn’t much more I can try on my own.