ImgCvrt for Mac

From Limit Point Software:

ImgCvrt is an application and contextual menu for converting image file formats, and optionally changing their dimensions. It works in batch mode. Converted images have the same name as the original, with the appropriate file extension, and saved in the same directory as the original provided a similarly named image does not already exist. Supported file formats are determined by QuickTime. (If a file by the same name does exist then the file name will be appended by a unique string.) To Use the Contextual Menu: Control-click on one or more image files in the Finder and select the ImgCvrt menu item for the file type you desire. To scale the image also, select the new dimensions from the bottom of the menu - note that this menu item will then be disabled. Select "No Scaling" to turn scaling off. It will then be disabled, and the previous scaling menu item will be enabled. The dimensions are created and edited in the "Sizes" tab of the preference pane. Use the "Add" button to add new entries in the list. Click down on the text in the list to begin an edit session to change the values. You can tab from item to item also. Use the "Delete" button to remove selected items in the list. Drag rows to reorder them in the list, they will appear in the same order in the contextual menu.o Use the Application: Drop image files onto the application icon in the Finder, or its main window. Use the "Preferences" window to select the file type to convert to. The advantage of the application over the contextual menu is that for batch processing of many files it displays progress information, and the contextual menu does not.