Is this possible

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cferron

Is this possible

Post by cferron »

Hello,

I would like to AUTO-ROTATE a lot of image with imagemagick. My camera have the orientation sensors and the EXIF header are marked accordingly. My questions:

1) Can we use ImageMagick to autorotate images base on their EXIF tag orientation field?

2) I have a dual quad core XEON, can I benefit of all this power? Can Imagemagick send a picture to b process to all available cores?


Thanks for your time.

Claude
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magick
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Re: Is this possible

Post by magick »

Modern versions of ImageMagick support auto-rotation.

Set the --enable-openmp configure command-line option to allow ImageMagick to take advantage of multi-processor systems for certain algorithms (e.g. blur, sharpen, unsharp mask, etc.).
cferron

Re: Is this possible

Post by cferron »

Does it take advantage of the MP with the rotate argument?
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magick
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Re: Is this possible

Post by magick »

Nope. We'll be adding additional MP algorithms over time but for proof-of-concept we limited the algorithms to anything convolution (e.g. blur).
Klaws

Re: Is this possible

Post by Klaws »

cferron wrote:Does it take advantage of the MP with the rotate argument?
Distribute your images into four different folders, or use a clever naming scheme and then run IM four times in parallel, each with one fourth of the images to process.

However, the processing may get I/O bound.

I am also not sure that ImageMagick performs a lossless jpeg rotation- AFAIK, it doesn't. A lossless rotation is quite fast and will benefit very little from multi-core execution (MP execution may be even slower because of disk thrashing and/or thread synchonization). You might consider to use a different tool for the job (one which does lossless jpeg transforms).

Best regards, Klaus
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