You can modify the properties of a clip by selecting options in the Interpret Footage dialog box.
For more information about using the Frame Rate options, see Change the frame rate of a file.
For more information about using the Pixel Aspect Ratio options, see Aspect ratios.
For more information about using the Field Order options, see Change the field order of a clip.
For more information about using the Alpha Channel options, see Set how an alpha channel is interpreted.