• 08-02-2009, 09:08 PM
    GB1
    Interesting Display of JPGs
    I am noticing something very unusual with my Palm Pre.

    It has the ability to store JPG images and display them on demand (much like the iPhone). I often do some cropping of my images and resave as a different file, then post (here for instance!) the image. And I now copy some of those images to my Pre.

    What's strange is, for a split second when I first select the image in the folder, the original full image displays !!! then the cropped version takes its place. It is like the JPG is keeping a small thumbnail of its original image inside.

    Never seen this before I got the Pre - does anyone have any info on this? Very odd

    G
  • 08-02-2009, 11:34 PM
    Skyman
    Re: Interesting Display of JPGs
    I am not sure but I can venture a guess:
    In a windows based environment the thumbnails of images are stored in their own file. This would ordinarily be updated as you made changes to the original file, but sometimes it is not or the thumbnail file might become corrupt in itself. In these cases it is possible for a file to have a thumbnail that is different (sometimes completely) to the file it is supposed to reprisent. I am guessing that the palm displays the thumbnail as it is loading the full image, but the thumbnail hasn't been updated probably because it doesn't update the thumbnails unless the file it new - to save processing power. Interestingly enough we use iphones and palm treos and pro's at work but I have never seen this before!
  • 08-04-2009, 09:56 AM
    GB1
    Re: Interesting Display of JPGs
    Skyman -

    but I never loaded the original file on the Palm. All it ever had was the cropped version (!) It appears that the JPEG is keeping a thumb of itself inside its own data, as strange as this sounds............

    I need to read the JPEG standard's doc as fun as that may be,

    G
  • 08-04-2009, 10:01 AM
    SmartWombat
    Re: Interesting Display of JPGs
    All JPEGs can contain their own thumbnail, yes.
    Unless you specifically don't store it.

    You can use the EXIF viewer add-on for Firefox to view jpg data, and as well as the exif it's also able to extract the preview thumbnail from inside the file.
  • 08-04-2009, 05:03 PM
    GB1
    Re: Interesting Display of JPGs
    Quote:

    Originally Posted by SmartWombat
    All JPEGs can contain their own thumbnail, yes.
    Unless you specifically don't store it.

    You can use the EXIF viewer add-on for Firefox to view jpg data, and as well as the exif it's also able to extract the preview thumbnail from inside the file.

    Got it; I don't see an option for not storing it in Corel PhotoPaint (or at least storing the correct image!). I guess I'll have to fish around on PS next,

    G