I developed "Edit Avatar" plugin.
Before:
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After:
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Compatibility
Q2A V1.5.x, 1.6.x, 1.7 [Updated 2014/12/19]
Edit function
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Crop (non rounded corners)
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Crop (with rounded corners)
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Rotate (Clockwise 90°)
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Rotate (Unclockwise 90°)
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Rotate (180°)
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Sharpen
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Scaling
Admin(customize) option
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Enable / disable plugin
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Aspect ratio (non, 1:1[square], 2:1, 3:2, 4:3, 16:9)
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Mask color on Image box
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Mask opacity on Image box
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Max width of Image box
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Layout of preview box
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Sampling rate
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Enable / disable rounded corner
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Max size of rounded corner (non - 50px)
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Background color of rounded corner
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Enable / disable rotate
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Enable / disable sharpen
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Enable / disable scaling
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Max ratio of scaling
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URL of edit page
You can try on my site.
Best regards.