Youtube darkens my videos when uploading

[Knightmessenger]

I haven't had this before but after uploading recent videos to youtube, they have appeared much darker than the actual video source file I used was. I put a lot of effort into adjusting the brightness and color correcting them so it really matters that they stay the same way I intended for them.
I have tested this on multiple screens and it is dark across the board. And it doesn't matter which computer I upload it from either, I edited them on a PC and used a mac at a college media lab to encode the videos on Compressor to optimize the quality.

optimized youtube video file


youtube screencap


And when I tried rendering the video on Compressor into an Mpeg 4, it turned out even darker on youtube (although looked less blocky).

So any idea why this is happening and how to make it stop?

At this point, is there a youtube video optimization program for PC I can just download. Because it's a real pain to only be able to prepare my videos when I have a chance to get to the library. Also, maybe the PC to Mac conversion is screwing up youtube. I don't know, I've been frustrated with the quality loss by youtube before. But I've never heard of it changing the attributes of the actual video for no reason.

[poisondeathray]

I edited them on a PC and used a mac at a college media lab to encode the videos on Compressor to optimize the quality.

it's a quicktime/mac issue , especially with h264 in mov

search for "quicktime gamma shift bug" , you'll find 1000's of posts . There are some workaround too , but it's just easier to use a PC since you have one

Basically , everything uses 2.2 gamma for display, but quicktime uses 1.8 gamma . When I mean everything, I mean everything - the entire broadcast industry, Europe, USA, internet, DVD, Blu-ray, Hollywood, Bollywood etc... the industry standard is 2.2. It's only Quicktime that displays with the screwed up gamma

[Knightmessenger]

Is there a setting in Compressor to use that will output the correct gamma? Would it be possible to turn it back into a windows format without reencoding so that it would maintain the compression quality and not shift in gamma?

I'm sure I could search for youtube video optimization for PC but would anyone have any recommendations. I would like to keep 30fps, convert to progressive scan, 640x480 and have the option to keep the audio at a high bitrate.
And is encoding as an Mpeg 4 especially good for youtube? I think that's what it makes the file.

[poisondeathray]

I'm assuming you've color corrected it or adjusted so you want it to look like the 1st video . But it doesn't look like that in "reality", only in quicktime (You were adjusting it using quicktime, so the actual Y' levels look like the 2nd video when using Rec601/709 for display)

You would have to reencode it and adjust to compensate . I think the newest versions of QT X and Snow Leopard have a 2.2 gamma display option, check for those settings

The only way I know 100% to use h.264 in mov without the gamma shift is to use uncompressed IYUV to encode through quicktime. Do a search, I've outlined this method before (on a PC)

There are several other methods, but I think they are display methods only. Once youtube gets it , it may or may not display consistently e.g.
http://www.videocopilot.net/blog/2008/06/fix-quicktime-gamma-shift/
Maybe it's good enough to "trick" youtube, give it a shot.


You can search for workarounds, but I don't think there is any other way to salvage it except to redo it.

Not sure why you would want to use quicktime to encode or decode, it's probably one of the lowest quality AVC encoders and decoders. I would just avoid it (not only the gamma shift issues, but low quality, introduces noise, lower quality chroma sampling). Decoders are supposed to give 100% identical results, but QT is the one case where that isn't so. I've posted some comparisions if you're interested (do a search)

But if you use high enough bitrate it can look ok. The real problem is what youtube does to everything (low bitrate)

[Knightmessenger]

Actually, I edited the video in Sony Vegas, it was not adjusted on Quicktime. The first screen is how it should normally look as that is the brightness in every video or clip I've handled other than what showed up in the youtube upload.

Is it possible to use compressor to encode the video but not with Quicktime? If I used my PC, I wouldn't have this problem. But I was really hoping to have an optimized video so it would be as blocky like some of my prior uploads.

[poisondeathray]

What are you doing that requires a mac / compressor or quicktime ?

Vegas has it's own issues as well with color management and studio rgb vs. computer rgb

[poisondeathray]

I just noticed your 1st video says "optimized youtube video file"...

But clearly there is grain, chroma noise - these are things that kill compression . You would benefit from denoising it before uploading to youtube .

Other tips like stabilizing the video, adding breaks, intros/outros - these help compression and bitrate distribution too.

Proper upscaling actually allow you to access higher bitrates. YT is the one case where going through upscaling efforts actually pays off

[Knightmessenger]

yeah, there's probably more I could do. But these videos are over a year old, it's long overdue that they are available. They don't have a lot of motion either so the compression is not that bad.
By optimized I meant, it was rendered in the program compressor so that it would be in the best format for a youtube upload. However, I've found that uploading the raw avi looks just about as good (maybe even better) and doesn't have the gamma shift. At this point, I've had enough screwing around and just want to post them all and call it a day.
judge if you wish:
"optimized" with gamma shift
http://youtu.be/DiN-i7Rc-A8

original avi uploaded
http://youtu.be/aJJL50zWZOo

I'm sure I could do better, especially if I did the whole upscale thing. Perhaps I'll try that for my next batch which will be action sports and benefit more since those have more motion. This avi version looks as good as I've gotten and I'd say in the 75% range of youtube quality of 480p. The sharp details and edges obtained from using the manual focus are very much intact.

The only problem is that some longer videos in avi are (predictably) over 2gb. It says you can download java to help with that and I just downloaded the most recent version like it said.
But it keeps saying I don't have Java installed.