Power Image Converter is a handy image conversion tool. It opens 100+ different formats, plus it converts to and from all formats supported, and you can flip, rotate, scale, watermark, change brightness, saturation, and hue over batches of photos at once. The program works fast even for large number of photos.
Supported formats are: JPG, PNG, GIF, BMP, TIF, TIFF, ICO, PDF, DPX, J2C, J2K, JP2, PAM, PBM, PCX, PGM, PPM, RAS, RGB, SGI, TGA, WEBP, XBM, YUV, VIFF, WBMP, WMF, WPG, XCF, XPM, AAI, ART, ARW, AVS, BPG, BRF, CALS, CGM, CIN, CMYK, CMYKA, CR2, CRW, CUT, DCM, DCR, DCX, DDS, DJVU, DNG, EMF, EPDF, EPI, EPS, EPS2, EPS3, EPSF, EPSI, EPT, EXR, FAX, FIG, FITS, FPX, GPLT, GRAY, HDR, HPGL, HRZ, JBIG, JNG, JPEG, MAN, MAT, MIFF, MNG, MRW, MTV, MVG, NEF, ORF, OTB, P7, PALM, PICT, PIX, PNM, PPM, PSD, PTIF, PWP, RAD, RAF, RGB, RGBA, RFG, RLA, RLE, SCT, SFW, SUN, SVG, TIM, UYVY, VICAR, AND VICAR.