Canon CRW raw files contain an embedded JPEG which is displayed when viewing images in main view. With Canon PowerShot cameras this image is only 640x480 pixels in size and isn't really large enough for proper viewing. The embedded JPEG can be replaced with a larger JPEG using the "Regenerate embedded JPEGs..." option under the "Tools" menu. This option will convert the raw file using the "As Shot" settings and replace the embedded JPEG with the converted image. The following dialog is displayed when this is selected:
The image size can be set between 100 and 3500 and is used to specify the size of the new embedded JPEG (the maximum size is limited to the resolution of the camera even if a larger value is entered here). Use the JPEG quality setting to specify the JPEG quality. A higher value gives better quality (and a larger file size).