QuickTime 3 Reference
QuickTime 1.6.1 introduced the Component Video codec, which stores data in YUV 4:2:2 format. The compression algorithm is not lossless, but the image quality is extremely high. The compression ratio is 3:2 (or 1.5:1). It does not support frame differencing. This codec is useful for certain video input solutions, such as those included in the Macintosh Quadra and Power Macintosh AV models. The YUV format is also useful as an intermediate storage format if you are applying multiple effects or transitions to an image.
By default, the Component Video compressor does not appear in the Standard Compression dialog box. However, it will appear if you hold down the Option key when clicking the compressor list to display the complete list.