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  1. Member
    Join Date
    Feb 2010
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    Sorry being late, i just remembered that i did a comparison of image quality between NVIDIA, AMD and Intel graphics. It was not so long ago. If anybody is interested in my observartions, check this out:
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  2. I only looked at the first three pictures (Nvidia, Intel, Radeon). The problem was the difference between PC (full range) and video (limited range) levels, and the rec.601 vs. rec.709 matrices. Both determine how YUV video in your source is converted to RGB for display.

    The first issue, limited vs. full range, is usually set in the graphics properties (sometimes in the player software). With Nvidia it's found in the Video section, advanced color adjustments. You can set Dynamic Range to Full (0 - 255), or Limited (16 - 235). All commercial distribution formats are limited range YUV and need to be converted to full range RGB for display. The correct setting in the Nvidia control panel is Full (0 - 255).

    The second issue, whether the rec.601 or rec.709 matrix is used to convert YUV to RGB is a little more complicated. In general, standard definition video uses the rec.601 matrix, high definition uses the rec.709 matrix. Using the incorrect matrix to display the video will make it look too green or too red (simplified):

    This continues to be an issue with media player software and graphics drivers/hardware. Some players/hardware default to one or the other. Some switch automatically depending on the resolution (but where exactly is the dividing point between SD and HD?). It's possible for the correct matrix to be flagged within the media file. Some players/hardware will pay attention to the flag, some won't. You can sometimes compensate for this by changing the rendering device in the player software (eg, Sync, EVR, VMR9, Haali, etc.).

    Both of these issues tend to vary with graphics card drivers and players. Updating to a different graphics card or graphics driver may change the defaults. And using different players may get you different results. In the end, all you've shown is how your computers and players were set up differently, not any inherent difference between the capabilities/qualities of the graphics cards.
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