ImageMagick convert scan: Difference between revisions
From WickyWiki
mNo edit summary |
mNo edit summary |
||
| Line 19: | Line 19: | ||
After scanning a document you may want to resize and compress the resulting image. You should scan with a higher resolution so you can have a better-quality lower resolution. | After scanning a document you may want to resize and compress the resulting image. You should scan with a higher resolution so you can have a better-quality lower resolution. | ||
<syntaxhighlight lang=bash> | <syntaxhighlight lang=bash> | ||
convert | convert "image.jpg" -resize 1500x -quality 85 "./new/image.jpg" | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| Line 25: | Line 25: | ||
The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white. | The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white. | ||
<syntaxhighlight lang=bash> | <syntaxhighlight lang=bash> | ||
convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 " | convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "./new/image.jpg" | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| Line 31: | Line 31: | ||
The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white. | The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white. | ||
<syntaxhighlight lang=bash> | <syntaxhighlight lang=bash> | ||
convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 " | convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "./new/image.jpg" | ||
</syntaxhighlight> | </syntaxhighlight> | ||
| Line 40: | Line 40: | ||
<syntaxhighlight lang=bash> | <syntaxhighlight lang=bash> | ||
convert "image.jpg" -crop 2x2+4+4@ +repage +adjoin " | convert "image.jpg" -crop 2x2+4+4@ +repage +adjoin "./new/image.jpg" | ||
</syntaxhighlight> | </syntaxhighlight> | ||
= Also see = | = Also see = | ||
* [[ImageMagick tools]] | * [[ImageMagick tools]] | ||
Revision as of 19:47, 3 April 2017
Compress, using quality
mkdir new
for file in *.jpg
do
nameext="${file##*/}"
name="${nameext%.*}"
ext="${nameext##*.}"
convert "${file}" -quality 85 "./new/${name}.${ext}"
done
Text document resize and quality
After scanning a document you may want to resize and compress the resulting image. You should scan with a higher resolution so you can have a better-quality lower resolution.
convert "image.jpg" -resize 1500x -quality 85 "./new/image.jpg"
Text document white threshold
The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white.
convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "./new/image.jpg"
White threshold
The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white.
convert "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "./new/image.jpg"
Split up picture
When you scan all your old photos, four at a time, you can use this to divide them up in quarters.
convert "image.jpg" -crop 2x2+4+4@ +repage +adjoin "./new/image.jpg"