I want to create a short animation with Blender 2.78c, which should be included in PowerPoint 2010 on a windows maschine. At the end, avi videos are not an option, because either the file size is incredible huge or the quality is not satisfying. In principle I can import an mpeg-1 compressed video into PowerPoint, which would be my prefered solution.
But here comes the problem (which is very similar to [Compression & Color change)
I created an animation and saved all frames as png images, which I would like to render as a combined mped file. For integrating the animation seamless into PowerPoint, I chose a white (hex-code #ffffff) background, which works very fine for a single png file. However, when importing the mpeg file, the preview image (the still file displayed before pressing play) also has a white background but when pressing play all subsequent frames have a slightly grayish background (hex-code #ebebeb).
I read that my problem could be related to a RGB to YCbCr conversion, but could anybody please tell me, how to correct this small shift? Or is it just not possible to have a background which is equivalent to #ffffff in an mpeg file? The same problem also occurs for H.264 and mpeg-2 or mpeg-4 compression.
Thanks a lot for your help!
Here is a minimalistic working example:
In an empty Blender file (version 2.78c), I switched to Video editor screen and added to track #1 a color (white, #ffffff in rgb). For the output I chose MPEG. Rendering a single frame as a png is fine, however rendering the mpeg-animation changes the white color to a grayish color (#ebebeb in rgb).
I checked now also the color "black" and as Troy_s suggested, also black is shifted by the value 16 (#101010) when viewed in PowerPoint and VLC (no difference between fullscreen and window mode).
However: When viewing the mpeg-1 encoded videos with Windows Media Player there is no distortion. Is it then right to say, that the encoding part worked, but the decoding failed?