Use this function to batch-convert picture files to another format.
A typical example is conversion of photos that you have scanned in in TIFF format into JPEG files for use on the Web. If your pictures are stored in JPEG format and you wish to do a large number of edits on them, and it is impractical to make these changes using the Batch Filter or during a single Editor session, then it can be a good idea to convert them to TIFF before the changes. The TIFF format is very useful when you are going to edit pictures, because you can save and re-save pictures to TIFF without any loss of quality, and you can use a higher color depth than in JPEG.
Use Edit | Convert File Format [Ctrl+Shift+F] in the Browser to reach this window. It is unavailable in the Editor (but see below).
There is a drop-down menu on the left side of the window where you can choose what format to convert to. Depending on that format, other settings are displayed at the bottom, such as compression type and color depth.
The right side of the window contains three menus for managing color conversion and one controlling how picture information will be saved.
The Image information menu sets whether all picture information, EXIF information only, EXIF information only minus a thumbnail (preview), or no picture information will be saved. If you use any setting other than "All" here, the picture and the color profile will automatically be converted to sRGB.
If the picture is open in the Editor, you can save it in any of format that you could convert it to. To do so, use File | Save As… [Ctrl+Shift+S]. In this window, you can both choose a format and give the file a new name and move it to a new path (folder).