MarkHastings
Senior HTF Member
- Joined
- Jan 27, 2003
- Messages
- 12,013
Ok, first off, I understand video in the computer world - SD video being at 720x480 and HD being either 1280x720 or 1920x1080....
Now in the computer world, all of these videos are 72 dpi. I realize that this is kind of a non issue in the video world (in regard to TV sets) since the bigger the set is, the bigger the pixels are, you really can't equate DPI because an inch of video footage on different screens is going to equate to varying sizes.
But the fact is, the video sources are at 72 dpi - the only reason HD has more resolution is because the video frame is larger. Unlike print where more resolution means higher DPI.
So being that, when a TV switches from SD to HD content, what exactly is going on? I assume the pixels are getting smaller to allow the size of the HD image to fit into the same area that the SD previously filled (just like changing your computers montior into a higher resolution). So is that what happens? the pixels get smaller?
If not, then what exactly are they displaying? and if so, what causes the pixels to shrink?
I guess I'd have to ask the same of computer monitors. If a monitor can display 640x480 at 72 dpi as well as 1024x768 at 72 dpi, since the physical screen doesn't get larger, then I assume the main difference has to be pixel size?
Now in the computer world, all of these videos are 72 dpi. I realize that this is kind of a non issue in the video world (in regard to TV sets) since the bigger the set is, the bigger the pixels are, you really can't equate DPI because an inch of video footage on different screens is going to equate to varying sizes.
But the fact is, the video sources are at 72 dpi - the only reason HD has more resolution is because the video frame is larger. Unlike print where more resolution means higher DPI.
So being that, when a TV switches from SD to HD content, what exactly is going on? I assume the pixels are getting smaller to allow the size of the HD image to fit into the same area that the SD previously filled (just like changing your computers montior into a higher resolution). So is that what happens? the pixels get smaller?
If not, then what exactly are they displaying? and if so, what causes the pixels to shrink?
I guess I'd have to ask the same of computer monitors. If a monitor can display 640x480 at 72 dpi as well as 1024x768 at 72 dpi, since the physical screen doesn't get larger, then I assume the main difference has to be pixel size?