dpi resize bug?

MagickWand for PHP is an object-oriented PHP interface to ImageMagick. Use this forum to discuss, make suggestions about, or report bugs concerning MagickWand for PHP.
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magick
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Post by magick »

The problem is that Photoshop ignores the JPEG/JFIF standard and grabs the DPI not from the image header but from an EXIF profile. ImageMagick does the right thing and sets the JFIF/JPEG resolution in the header but does not modify the EXIF profile. Adobe has had a history of ignoring standards and doing whatever suits them. Another example is Photoshop inverts the CMYK values in a JPEG image (see the JPEG source distrubution documentation for details).
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magick
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Posts: 11064
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Post by magick »

The -strip option can be used to strip the EXIF profile.
dominus

Post by dominus »

does the above code actually change the resolution of the image or it only changes the way the resolution is recognised by image viewing and editing software
nsh
Posts: 27
Joined: 2006-05-16T01:52:23-07:00

72 dpi default if exif missing...

Post by nsh »

I think that photoshop's set's the dpi to 72 if the non standard dpi info is missing... so i wonder if strip image really is a workaround...
snowbydave1

Anyone guide me how to handle 300 dpi PhotoShop file resolut

Post by snowbydave1 »

I am opening file with whose resolution are already set 300 dpi with PhotoShops CS2 window.

I am using MagickWand library for getting image resolution. When I test it on my localhost it will display 300 x 300 dpi resolution.

Same code I had uploaded on my server. I had uploaded same image 300 x 300 dpi resolution there. But here I am facing problem.

MagickWandGetResolution function return 72 x 72 dpi resolution. With the help of this forum I had open original image in FireWorks & simply save as with other name. Then uploaded this image on live server it will display 300 x 300 dpi resolution.

This has solved my problem. But all of my client or end user doesn't know this and most of then are using only Adobe PhotoShop.

Please anyone guide me how to handle 300 dpi PhotoShop file resolution with MagickWand.


Thanking you,


Snowby Dave
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