I use WinVN, and although it appears to properly decode some pictures (MIME/Base64-encoded) posted by Macs, I can't see the pictures.
WinVN can not handle Mac-posted JPEG files, which include a thumbnail of the picture. Sometimes only the thumbnail will be visible, and sometimes nothing at all.Save these files as text (use file extension .B64) and decode them with WinZip, UUDeview or a similar decoding program. Unfortunately, there's no way to see by the subject line if you're dealing with this kind of file. If you download it without decoding, you will see the image part starting with "AAUABwACAA...", whereas a normal JPEG file always starts with "/9j/...". When you encounter new posters, it's a good idea to download the first article without decoding, so that you can look at it and determine if this problem will occur.
I use Netscape/Explorer/Agent/Gravity, and I can't decode some pictures (MIME/Base64-encoded) posted by WinVN and some early Netscape versions.
This is because WinVN and Netscape 2.x don't produce proper MIME headers. That means your newsreader doesn't know what name it should give to the file. WinVN itself uses information from the article's subject line to produce a filename, so it can decode these files without any problem. Download these articles without decoding and save them as text (use file extension .B64). You need to take notes of the filenames, because you may have to name the resulting files manually. Use WinZip to decode the file. If there's something in the subject line, which can be used as a filename, WinZip will use that. Otherwise the file will be called "unknown.001" or something like that, and you will have to rename it by hand to the proper filename.
-- I am sure that the decoding process in my newsreader functions OK, but I *still* can't see the picture I have downloaded, and it doesn't help to download as text and decode with a stand-alone decoder.
Well, then it's not a decoding problem. The trouble is probably with the file format and your viewer. JPEG formats, in particular, may cause problems. To begin with, there is a "progressive" type of JPEG, which cannot be handled by all viewers. Then there is some pictures manipulation programs, which add extra information in the JPEG file header (Adobe PhotoShop, for example). That causes some viewers to choke. For the Windows platform, ACDSee is unbeatable when it comes to handling different file formats.
