changing file extension from .html, .jpg, to .mov now i'm confused.

Don't know how you are "altering it's format" but if you check "show file extensions" in the finder prefs, all will become clear...

Changing a file's extension will not necessarily change the file's format. Unless you're performing some kind of conversion (like through a Save as... command), the data in the file will remain unchanged, and should still tell you what kind of file it is under File->Get Info.

So if you did change the extension of your file from .html to .jpg to .mov, you haven't changed the actual format It would still be an HTML file. In fact there is no way an HTML file can be viewed as a jpeg or mov without some serious conversion by either an image or video editing program.

Bryan

Open the Terminal application in the /Applications/Utilities/ folder, type in 'file' without the quote marks, drag the file into the Terminal window, and press Enter. This command may tell you what format the file is in, and you can use this information to give it the original extension.

(16648)

After typing in file, add a space, drag the file in, and press Enter. This will likely show you what type of data is in the file, and you can work out its extension from that.

(16695)

Hi

Indeed there is something strange about that file. I just changed the extension of an rtf file on my Desktop to jpg. Like you I couldn't open it with a double-click and File Info would just say it was a jpg, which isn't helpful. But when I tried Niel's Terminal solution it provided the correct info, thus:

file /Users/matthew/Desktop/Arbeidsgruppe.jpg
/Users/matthew/Desktop/Arbeidsgruppe.jpg: Rich Text Format data, version 1, Apple Macintosh

For some reason it is not reading your file properly at all.

Matthew Whiting

It won't tell you the original extension, you'll have to figure it out from the information it provides. I have a screenshot in the folder screens on my Desktop, and changed its extension to .doc, then used the file command. I suspect you did that part incorrectly.

1. Type

file

2. Hit the spacebar
3. Drag the file into the Terminal window and drop it
4. Hit the Return key

Here's what my command looks like:

-bash:~francine$ file /Users/francine/Desktop/screens/dylan.doc

And here's what Terminal replies when I hit the Retrun key:

/Users/francine/Desktop/screens/dylan.doc: PNG image data, 880 x 661, 8-bit/color RGB, non-interlaced

It repeats the file location, then informs me it is actually a PNG image. So I would add back the extension for a PNG image, which is .png. With something that was originally a jpeg, you'll get this:

/Users/francine/Desktop/screens/lindsaylogo.mov: JPEG image data, JFIF standard 1.01

You would then add the typical .jpg extension.

You don't accomplish anything by changing extensions on files, except to completely confuse the system. To convert something from one format to another you need a program that can actually change the contents of the file.
Francine


Francine
Schwieder

It's a StuffIt .sit file. For instance I have the file

dlx551.sit

If I do the file command on it I get this:

dlx551.sit: StuffIt Archive : StuffIt Deluxe\342\204\242 5.5.1 Updater

Thus, double clicking dlx551.sit launches StuffIt Expander, which produces the unstuffed file "StuffIt Deluxe™ 5.5.1 Updater"--the funny \342 number things are for the trademark gizmo. In other words, file is telling you that what you've got should have the extension of .sit, and it will expand into "ImageEdit 1.1 OS X...."
Francine


Francine
Schwieder