How to Use DENSITY setting BEFORE Vector Designation

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jpeni
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How to Use DENSITY setting BEFORE Vector Designation

Post by jpeni » 2017-11-26T14:46:32-07:00

It is recommended to use the -density option BEFORE the vector file format is specified in the command to preserve output quality. For example:

convert -density 300 "C:\Originals\File.eps" -depth 8 "C:\Previews\File.PNG"

This works for individual images, but how do you enter -depth options BEFORE specifying the vector format in the following recursive command?

FOR /R %a IN (*.eps) DO convert -depth 8 -threshold 40% -alpha off "%~a" "%~dpna.png"

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fmw42
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Re: How to Use DENSITY setting BEFORE Vector Designation

Post by fmw42 » 2017-11-26T14:55:44-07:00

Sorry I do not use Windows so this is a guess. But you need to read the input first apart from the density and put your other arguments after reading the input.

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FOR /R %a IN (*.eps) DO convert -density 300 "%~a" -depth 8 -threshold 40% -alpha off  "%~dpna.png"

jpeni
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Re: How to Use DENSITY setting BEFORE Vector Designation

Post by jpeni » 2017-11-26T16:18:46-07:00

Thanks for your guess, but you did not use the -density option BEFORE specifying the VECTOR format. For vector graphics, ImageMagick has both a render resolution and an output size that are independent of each other so the density must be specified BEFORE the VECTOR format.

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Re: How to Use DENSITY setting BEFORE Vector Designation

Post by snibgo » 2017-11-26T16:27:05-07:00

Fred's guess is correct. He had:
... convert -density 300 "%~a" ...
In the "convert" command, we specify the "-density" before reading the vector file, so the software that rasterizes the vector data will use that dpi.
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jpeni
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Re: How to Use DENSITY setting BEFORE Vector Designation

Post by jpeni » 2017-11-26T16:44:31-07:00

Thanks. Now I recognize how Fred's placement of the "%~a" option placed the -density BEFORE the eps was specified.

Please: For those of us who need guidance - when you provide a suggested solution - please explain how your solution fixes the stated problem so we can understand.

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