quick facts - maybe outdated

Video File Size (in MB) =

(Duration in seconds) x (Horizontal width) x (Vertical length) x (Bits of color per pixel) / (8 [8 bits in a byte]) x (frames per second)

Uncompressed 24-bit Video
("legal" video is 29.97 fps & thus smaller; YUV color space is 16-bit so files are smaller)

640 x 480 pixels = 307,200 pixels per frame
307,200 x 24 bits x byte/8 bits = 921,600 bytes per frame
921,600 x 30 frames per second = 27.648 MB

Audio File Requirements =
(in bytes per second)

Sampling frequency (KHz)
x Sample size (1=8-bit,2=16-bit; eg, 8-bit/sample divided by 8 bits per byte)
x Channels (1=mono, 2=stereo)