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Old 05-02-2018, 02:22 PM
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old_tv_nut old_tv_nut is offline
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Join Date: Jul 2004
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I did an experiment. I have a DTV converter that includes playback of multimedia from a USB port, so I created an Indianhead test pattern jpg with two blue stripes in Photoshop.

The reason for making the stripes blue is that the media player always has its color burst on, so if phasing the horizontal hold over to the stripe works, the stripe color should change from blue to yellow-green. As you can see it works (at the extreme of the hor hold setting just before it loses sync)!

This is not an exact reproduction for a couple of reasons:
1) the only way I could produce the stripes in Photoshop affected the luminance as well as the chroma, that is, the stripes are actually darker than the background.
2) I don't know exactly what scale factors the media player uses to translate the jpg resolution to the NTSC output. The jpg is 720 pixels wide, but maybe it would work better with 640 or something else.
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