problem sending pictures

Discussion in 'Misc' started by tom koehler, Dec 8, 2011.

  1. tom koehler

    tom koehler Guest

    I'm running OS 10.6.8 and using mac's mail program called "Mail". I'm sending
    pictues, JPEG format. Get info says the file size is 2.3 mb. I send the
    picture, and somehow the file is compressed to about a tenth of the file
    size, and is quite small physically when displayed. An attempt to zoom in
    shows the picture to be severely pixellated.
    Now, I am at a loss as to why this compression is happening, and why the
    picture is getting shrunk so much. Doesn't seem to matter how darn big the
    picture is when I send it, when it arrives it is shrunken and useless when
    zoomed larger.
    What am I doing wrong? If my apparently failing memory serves me, I never had
    this problem in years past. I'm so frustrated now, I can't think straight.
    tom koehler
    tom koehler, Dec 8, 2011
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  2. tom koehler

    tom koehler Guest

    correction, I'm sending in PNG format.
    tom koehler, Dec 8, 2011
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  3. There's an option somewhere (a pop-up menu at the bottom of the compose
    message window from memory) that allows you to set the size of the images.

    2.3MB is pretty big for a JPEG image though. Depending on what they
    receiving person is using the images for, you might want to still have
    smaller than full size images, especially if they are on a dial-up

    Helpful Harry :eek:)
    Helpful Harry, Dec 8, 2011
  4. There's a tiny menu in the lower-right of the message window labeled
    "Image Size." Set it to "Actual Size."

    If that's not it, it's possible that the mail server is re-encoding your
    message. It shouldn't, but some do. MS Exchange is one of them.
    Kevin McMurtrie, Dec 8, 2011
  5. tom koehler

    Chris Ridd Guest

    Another possibility - may be a long shot - is that the image has a
    custom icon encoded in the resource fork, Mail is sending both forks
    and the recipient is looking at the custom icon and not the image?

    You could test that by selecting the original image in Finder, doing a
    Get Info, selecting the icon and pressing delete. Then resend the image.
    Chris Ridd, Dec 8, 2011
  6. tom koehler

    Suze Guest

    Have you tried zipping it?
    Suze, Dec 8, 2011
  7. tom koehler

    tom koehler Guest

    Thank you all, for your speedy and helpful responses!!
    For some reason, I never noticed the little box in the lower right corner of
    my screen, to select image size. Not expecting to see one, I guess I never
    saw it. I do not recall ever using an option like that in the past. A flimsy
    and weak excuse, but the only one I have.
    Your solutions were on the money and simple enough that even I could
    implement the solution.

    for Suze, I have not tried zipping the picture. That is not something I have
    ever done. I'm not entirely sure how I would do such a thing. I am grateful
    for your response and suggestion, all the same.

    tom koehler, who can dismantle a whole house or operate a nuclear reactor,
    but is often stymied by his own computer
    tom koehler, Dec 8, 2011
  8. tom koehler

    Patty Winter Guest


    Tom, the zip/unzip utility has been built into Mac OS X for some years
    now. Just select the photo and choose "Compress <filename>" from the
    File menu.

    I'll let someone else explain when that's most apt to be useful. I just
    tried it on a random photo and the "compressed" file was nearly the same
    size as the original (2.21MB vs. 2.24MB)...

    Patty Winter, Dec 8, 2011
  9. Many image formats already use compression, so putting them in a Zip
    archive doesn't achieve anything in terms of reducing the filesize (in
    fact it can make them a bit bigger).

    it can still be a useful way of preventing some servers and email
    applications from doing silly things (e.g. seeing images as being inserted
    in the email's message rather than being attached).

    The only problem could be that a Windows user or someone using an older
    version of the Mac OS on the receiving end doesn't have a Zip application
    to unZip / unarchive the files, but there are plenty of free ones around
    they can install.

    Helpful Harry :eek:)
    Helpful Harry, Dec 8, 2011
  10. tom koehler

    John Varela Guest

    JPEG is already a compressed format so there's little to be gained
    by ZIPping it. The OP has corrected himself and said he is using
    PNG; I don't know if that's a compressed format. In any case, I
    agree with other posters that either the OP has selected a small
    format instead of "actual size" in or else the recipient
    has somehow managed to look at the thumbnail instead of the image.
    John Varela, Dec 8, 2011
  11. PNG is compressed with predictive encoding and deflate.

    As the pixels of the image are read, a filter tries to predict the next
    pixel based on past pixels. The difference between the predicted pixel
    and the actual pixel is fed into the common 'deflate' compression
    algorithm. In areas lacking sharp details, the predictions are good so
    deflate receives a stream of small numbers that compress well.

    Decompression is the reverse process. Using an algorithm exactly
    matching the compressor, past pixels are examined to predict the next
    pixel. The difference between the prediction and actual pixel is read
    from 'inflate' and used to make the current pixel.
    Kevin McMurtrie, Dec 9, 2011
  12. tom koehler

    Suze Guest

    That was what I had in mind, just to keep the file from being munged by
    a mail server.
    Suze, Dec 9, 2011
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