Camera EXIF (ISO, shutter, lens, GPS coords) is preserved by default during JPG → JPEG when both formats support metadata. Use the privacy option to strip metadata before download if you need to share images without geolocation.
For JPG / WebP, quality 75-85 typically gets the JPEG 60-80% smaller than JPG with no visible difference at normal viewing distance. For lossless JPEG (PNG, TIFF), expect smaller savings — usually 5-30% via better deflate / LZW compression. JPEG是最喜欢的推广相机、扫描仪和Unix源软件,而且得到普遍认可。
