Image tearing on Mirai DTL-832E600 LCD TV
January 16th, 2009 by freenerdAbout half a year ago I decided to get a Mirai DTL-832E600 HD-ready LCD TV as they happened to be on sale at a local pc hardware retailer. Although I only paid around €500 for the (at the time) noname monitor, I quickly came to realize how good the quality was, as it had the best menu-driven user interface I have ever seen in a television set and was packed with all sorts of features I wasn’t going to need at the time - such as component input, optical audio output and a digital tuner with a card slot.
Just a few months ago, another person viewing my screen (then using VGA input from a HTPC) noticed a fixed horizontal line, about a third of the screens height from the top; the line was only visible if the screen displayed quick flashing or transition to white. At first I thought the LCD panel itself might be damaged and considered sending it in for warranty repairs. Since I liked having an LCD TV around, I first set out to try to trace the problem and see if I could fix the problem myself.
The first thing I did was get a DVI->HDMI cable and connect the screen digitally. This didn’t remove the horizontal line, but it did cause it to move around smoothly. This caused me to think that the vertical refresh rate might be wrong, and that there was a constant under- or overscan. Adjustments to the Xorg’s configuration had no noticeable effect. To see if this was due to my GNU/Linux nVidia drivers or my graphics card, I tried out the same thing with a laptop running Windows Vista. The same problem persisted.
Now, last night I got an itch that maybe I could try playing up video with the vsync/sync to vblank option enabled for the driver. And it worked! Using nvidia-settings in ubuntu, I enabled both “sync to vBlank” settings for the driver and started using the opengl2 (gl2) video output interface. This removed all traces of the image tear and the image is better than ever.
I hope this post will help other lost souls out there, as I googled around for this problem for days, finding no solution. This will probably apply to other Mirai LCD TV’s and other brands too. So if you are experiencing image tearing (for some reason called “shearing” by some), then try enabling the vsync options on your display driver and using the right output driver in your media player.
Posted in Solved | No Comments »
