Smaller output frames

Videot wrote on 9/1/2004, 5:03 PM
I was under the impression that for PAL the only official MPEG2 size was 720 x 576. Now I here that there are 2 other official frame sizes which all DVD players should have support for the smallest of these is 360 x 288. This suggests that the file size would be one quarter that of the full frame - is this correct? Would using such a frame size be of any use when dealing with video of poor quality like old VHS or would doing so only make matters worse? Would this frame size display full size on your TV or would you have to reset your DVD players settings?

Comments

bStro wrote on 9/1/2004, 5:10 PM
The different sizes are displayed the same on your television. The smaller sizes are just less quality.

Rob
Videot wrote on 9/1/2004, 5:17 PM
Is the file size just a quarter that of the full size version thus allowing you to put 4 times as much on a disk?
Chienworks wrote on 9/1/2004, 6:17 PM
The file size is determined by the bit rate and the length of the material. The frame size has nothing to do with file size, at least not directly. However, on the other hand, indirectly, you can generally encode smaller frames at a lower bitrate, so indirectly, you can produce a smaller file more readily with smaller frames. However (on the third hand, so to speak), reducing only the frame size while using the same bitrate will result in the same file size as the larger frames. And, on the fourth hand, reducing the bit rate will decrease the file size even if you do use full size frames. So, as you can see, it's the bitrate that matters, not the frame size. It's just that lower bitrates can look better with smaller frames than with larger frames.