How are images stored in container fields?

December 27, 200520 yr

How does FM7/8 store images in container fields (under Mac OS X)? I have the feeling that if insert a JPEG, it converts it to some other lossless format internally (PNG?). I also remember reading a few months ago that you could get different results depending on whether you inserted the picture via drag & drop, cut & paste, or the insert picture command.

Any advice?

December 28, 200520 yr

While testing IWP in FM7 I found that all graphic elements except .gif are converted to very lossy JPEGs that are highly pixelated. Graphics were pasted from Photoshop and inserted using Insert Picture in both Layout and Browse mode, with gif, jpg, tif, png, bmp, and pct formats. FileMaker client displays whatever was pasted/inserted. A 200% blow-up showing the pixelation is shown above. The actual button graphic looks like the .gif.

These results indicate that Insert Picture does not change the format.

Pasting is another story... When a Mac OS X application puts an object on the clipboard, it can associate several formats for the data, so an app could put a .jpg on the clipboard as both a .jpg and in some lossless manner. I have no idea how FileMaker prioritizes/chooses multiple graphic formats on the clipboard, nor how the clipboard behaves in Windows.

December 28, 200520 yr

When a Mac OS X application puts an object on the clipboard, it can associate several formats for the data, so an app could put a .jpg on the clipboard as both a .jpg and in some lossless manner.

This is news to me. I often check the format of the clipboard (in Finder, Edit > Show Clipboard), and I have never seen more that one format there. Can you give an example of how to get a "dual" clipboard?

December 29, 200520 yr

The Finder is over simplifying.

If you have the Developer Tools installed, look in /Developer/Applications/Utilities/Built Examples, there's a Clipboard Viewer which shows the multiple attributes of an item on the clipboard.

I tried copying part of a GIF graphic in Preview, Clipboard Viewer showed both TIFF and PICT formats for the data. I also tried some text in TextEdit (in RTF mode), Clipboard Viewer showed RTF, ASCII, 'ut16' with 'ustl' (Unicode text and style), and 'TEXT' with 'styl' (Mac's historical way of encoduing styled text).