What’s The Issue?

Standard Def video captured to BT.601 standards uses non-square pixels. That is, 720x576 for PAL, 720x480 for NTSC. Further, the active picture area is 8 pixels inside the side edges. To encode these non-square-pixel files in the correct proportion (without cropping), one needs to know the Sample Aspect Ratio, the ratio between the frame size and the desired display size or DAR. The only accurate way to do this is to have a video of a wheel and measure the dimensions of the wheel. To do this, open the file in VDub. RC on the video and choose 1:1 Pixel (Square). Measure the height of the wheel in pixels. Measure the width of the wheel in pixels. Divide the height by the width: this will reveal the SAR. PAL values: 1.09 = 12/11 1.067 = 16/15