Videos are dark when shown on Mac

[jojo8]

Hi,
Newbie here.

Most videos I download show up very dark on my Mac laptop's. This is with the brightness all the way up.

To be more specific, it isn't all levels that are dark, it's just the mid (and darker) tones that seem to be much darker. I think this is called "black crush", the levels are shifted toward the dark end. At least that's what my Googling turned up. The cause seems to be how the video is transferred (analog rather than digitally).

Is this more pronounced on a Mac vs. Windows? (due to differences in the displays' gamma)

My question is: what can be done about it, on my end? Is there a player that can adjust for this "real-time"? Or can I re-convert it, and in the process, alter the brightness and contrast?

What software would be best to use for this?

Thanks,
jj

Mac PowerBook G3/400; OS X 10.3.9

[Case]

a. Is your monitor calibrated? At least optimize it using System Preferences>Displays>Color>Calibrate.
b. What kind of videos? MPEG videos shown in QuickTime Player tend to render darker, but other formats and other players should be good.

[jojo8]

Thanks for your reply.

a. Is your monitor calibrated? At least optimize it using System Preferences>Displays>Color>Calibrate.

Yes, calibrated.

b. What kind of videos? MPEG videos shown in QuickTime Player tend to render darker, but other formats and other players should be good.

I hadn't noticed before, but all are mpeg4's -- either "avi" or "mpg" or "mp4" extensions, but when examined in VLC player, the details show that all are mpg video format.

But being MP4 format isn't the cause: many -- but not all -- of these videos are universally dark. Those that are dark, regardless of the player application (I've tried half a dozen), will show near identically across the players.

Is there any way to modify the media files prior to or during playback to increase the brightness and/or contrast values?

Thanks,
jj[/quote]