Bad Youtube Compresion

[Bart de Graaf]

Hi all,

Recently we've shot a video for the Dutch carnaval market.
We shot 3k 48 fps on a scarlet.

The video was exported as a .mp4
We already did some tests to see how youtube would react to different compressions.
Thus far with with horrible results. We noticed that when the pasing of the edit is slow, the video quality is way higher.

The original video in .mp4 is very ...very.. detailed and clean.

The video you guys can see here is;

3k hd
25 fps
100 mbs
Profile: high
Level: 5.1
Keyframe distance: 25

Rendered at maximum depth
and exported with 'use maximum render quality' on.

Anyone got a slight idea whats going on here?
It is kinda horrible to show the material to clients this way

here is a link:
http://www.youtube.com/watch?v=011pN5k11yU


Feedback is MOST welcome!!!

Bart

 

[Dominik Muench]

Creating mp4s from mp4s again is not a good idea. why not export H264 instead as mov for example ? that ll work with youtube/ vimeo and will give you better results.
I had to export a few mp4s for web the other day and tried mpeg streamclip and noticed that even at 100% quality, its creates horrible results with bad artefacts.

 

[Bart de Graaf]

Creating mp4s from mp4s again is not a good idea. why not export H264 instead as mov for example ? that ll work with youtube/ vimeo and will give you better results.
I had to export a few mp4s for web the other day and tried mpeg streamclip and noticed that even at 100% quality, its creates horrible results with bad artefacts.

I understand, but I cannot export it on its original resolution if i try to make mov. h264 in adobe media encoder.

 

[Joel Arvidsson]

Upload as proress or h264 with constant bitrate. Dont forget to up the bitrate?

 

[Pete Lutz]

Yes, proress or h264, and you can enter in any resolution you want.

 

[Alexander Mejia]

Youtube has a max resolution of 3840x2160. If you exceed any of those dimensions you will be downsampled (sometimes not in a very pleasing way)

On top of that you cannot exceed 30FPS. I would reccomend exporting a 24FPS version of your film, since 25 FPS doesn't decimate right

YouTube is a very compressed beast, meaning you cannot preserve all of the details in your original footage. But you can choose which details to knock down by pre-processing different channels of the footage.

I find that knocking off details in the cB and cR channels by either de-noising, or blurring can give you extra bits to hold data in the Y channel. Human eyes are notoriously bad at seeing chroma and luminance information. By "smoothing" over this data in the cB and cR channels, you will increase the ammount of bits spent in the Y (picture) channel, creating more detail than had you just uploaded the file straight.

If you knock out too many details in the cB and cR channels you'll experience banding (once they've been compressed to 4:2:0) You can add static dithering back into these channels to prevent any banding, without decreasing the efficiency of your encode.