126 Chapter 3
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ManualUnspecified - this mode disables any compression to allow compatibility with
any applications that do properly follow the GIF specification.
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ManualLeave - this mode prevents the disposal of the preceding frame when displaying
the current frame.
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ManualUseBG - this mode replaces the preceding frame with the background color -
usually transparent - when displaying the current frame.
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ManualUsePrev - this mode restores the preceding frame before displaying the next
frame.
NOTE: If the original image has more than 256 colors, you must apply the reduce() function
before the save() function.
Additional Parameters for GIF and PNG Files:
Interlaced - if set to “true”, turns graphic interlacing on. The default is false.
Additional Parameters for JPEG Files
Quality - sets the level of quality on a scale from 0 to 100. The default is 85.
Progressive - if set to “true”, allows browsers to load the image in stages. The default is
false.
Baseline - if set to “true”, saves the JPEG using the optimized baseline format. The
default is false, or the standard baseline format.
Colorspace - specifies the colorspace format in which the JPEG is saved. The default is
“Std”. Other valid colorspace format options are:
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“Gray”
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“RGB”
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“YUV”
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“CMYK”
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“YCCK” (usually compresses better when saving CMYK data)
Highdetail - if set to “true”, improves overall image quality. The default is false, unless
the Quality parameter is set to 100, in which case it is automatically enabled.
NOTE: This option yields better results with drawings than photographs.
Dontoptimize - disables the optimize feature of the JPEG writer. The default is false.
Additional Parameter for PNG Files
Compressionlevel - sets compression level. The default is 6. (A Compressionlevel
value of “9” can be very slow in processing.)
Additional Parameters for EPS Files
binary – if set to “false”, writes an ASCII EPS file. If not specified, it defaults to “true” and
writes a binary EPS file.
preview – if set to “false”, writes an EPS file without a TIFF preview. If not specified, it
defaults to “true” and writes a preview TIFF to the file.
debabCompat – if set to “false”, writes a smaller file that is not compatible with
DeBabelizer. If not specified, it defaults to “true” and writes larger, but DeBabelizer
compatible file.
