doc:appunti:hardware:canoscan_9000f_mark_ii_positive_scan
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| doc:appunti:hardware:canoscan_9000f_mark_ii_positive_scan [2019/12/23 17:18] – [ICC profile] niccolo | doc:appunti:hardware:canoscan_9000f_mark_ii_positive_scan [2020/01/01 17:02] – [Extract the embedded color profile from an image] niccolo | ||
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| * Apply, change or strip **color profiles**. | * Apply, change or strip **color profiles**. | ||
| - | === Inspect a file === | + | ==== Inspect a file ==== |
| This command display the image format, bit depth, colorspace, embeddedd ICC profile, max and min values of the color components, etc. | This command display the image format, bit depth, colorspace, embeddedd ICC profile, max and min values of the color components, etc. | ||
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| </ | </ | ||
| - | === Add a color profile to an image === | + | ==== Remove the color profile from an image ==== |
| + | |||
| + | This command will **strip** any comment and **profile** from a source image, it **does not alter the pixel data** values (**WARNING**: | ||
| + | |||
| + | < | ||
| + | convert image.tiff -strip image-no-profile.tiff | ||
| + | </ | ||
| + | |||
| + | ==== Add a color profile to an image ==== | ||
| This command will **strip** any comment and **profile** from a source image, then it adds a color profile from an ICC file, **embedding** it into the image, **without altering the pixel data** values (**WARNING**: | This command will **strip** any comment and **profile** from a source image, then it adds a color profile from an ICC file, **embedding** it into the image, **without altering the pixel data** values (**WARNING**: | ||
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| </ | </ | ||
| - | === Convert an image to another color profile === | + | ==== Convert an image to another color profile |
| The following command will ignore any embedded profile (-strip), **apply the Canon custom profile**, than **convert** the image to the **standard sRGB color profile** (color space). Finally it removes from the resulting image any metadata about profile: | The following command will ignore any embedded profile (-strip), **apply the Canon custom profile**, than **convert** the image to the **standard sRGB color profile** (color space). Finally it removes from the resulting image any metadata about profile: | ||
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| </ | </ | ||
| - | The resulting image will not have any metadata about color profile, so the sRGB will be assumed by default. The pixel data values are converted from the original Canon colorspace to the sRGB one (one-way lossy operation). | + | The resulting image will not have any metadata about color profile, so the sRGB will be assumed by default. The pixel data values are converted from the original Canon colorspace to the sRGB one (one-way lossy operation). NOTICE: you have to provide the // |
| - | **NOTICE**: the Debian package **colord-data** provides the file **/ | + | ==== Extract |
| - | + | ||
| - | === Extract | + | |
| This command will extract the ICC file embedded into a file: | This command will extract the ICC file embedded into a file: | ||
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| It is not possible to extract the ICC file if the colorspace is just declared into the metadata, but not embedded as a profile. In this case you can search instead into the **/ | It is not possible to extract the ICC file if the colorspace is just declared into the metadata, but not embedded as a profile. In this case you can search instead into the **/ | ||
| - | === Set a different colorspace === | + | ==== Examine an ICC color profile ==== |
| + | |||
| + | We can use the command line tool **exiftool** from the Debian package **libimage-exiftool-perl**. | ||
| + | |||
| + | To examine a profile embedded into an image: | ||
| + | |||
| + | < | ||
| + | exiftool -icc_profile: | ||
| + | </ | ||
| + | |||
| + | To examine an ICC profile file: | ||
| + | |||
| + | < | ||
| + | exiftool profile.icc | ||
| + | </ | ||
| + | |||
| + | ==== Set a different colorspace | ||
| This command will change the colorspace of an image. Just **the metadata is changed**, no data conversion is performed: | This command will change the colorspace of an image. Just **the metadata is changed**, no data conversion is performed: | ||
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| **NOTICE** that some combinations of **image format** and **colorspace** are not allowed, e.g. you cannot create a TIFF file into the RGB colorspace, or a PNG file into the CIELab colorspace. | **NOTICE** that some combinations of **image format** and **colorspace** are not allowed, e.g. you cannot create a TIFF file into the RGB colorspace, or a PNG file into the CIELab colorspace. | ||
| - | === Convert to a different colorspace === | + | ==== Convert to a different colorspace |
| This command will **update metadata** about the used colorspace, **pixel data** values are **transformed** into the new colorspace: | This command will **update metadata** about the used colorspace, **pixel data** values are **transformed** into the new colorspace: | ||
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| convert image.tiff -colorspace CIELab image_lab.tiff | convert image.tiff -colorspace CIELab image_lab.tiff | ||
| </ | </ | ||
| + | |||
| + | Some known colorspaces are: **sRGB**, **RGB**, **CIELab**, **Gray**. To list colorspaces supported by Imagemagick, | ||
| An **ICC color profile** is **not embedded** into the file, so the software used to open the resulting file must be aware of that colorspace by itself. | An **ICC color profile** is **not embedded** into the file, so the software used to open the resulting file must be aware of that colorspace by itself. | ||
doc/appunti/hardware/canoscan_9000f_mark_ii_positive_scan.txt · Last modified: 2020/01/02 17:40 by niccolo