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489.
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Every device that is processing color should have it's own ICC profile and when this is achieved the system is said to have an <em>end-to-end color-managed workflow</em>. With this kind of workflow you can be sure that colors are not being lost or modified.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisprofile.page:33
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494.
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The human visual system is not a simple RGB sensor, but we can approximate how the eye responds with a CIE 1931 chromaticity diagram that shows the human visual response as a horse-shoe shape. You can see that in human vision there are many more shades of green detected than blue or red. With a trichromatic color space like RGB we represent the colors on the computer using three values, which restricts up to encoding a <em>triangle</em> of colors.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:25
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495.
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Using models such as a CIE 1931 chromaticity diagram is a huge simplification of the human visual system, and real gamuts are expressed as 3D hulls, rather than 2D projections. A 2D projection of a 3D shape can sometimes be misleading, so if you want to see the 3D hull, install <code>gnome-color-manager</code> and then run <code>gcm-viewer</code>.
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(itstool) path: note/p
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(no translation yet)
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Located in
C/color-whatisspace.page:37
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496.
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sRGB, AdobeRGB and ProPhotoRGB represented by white triangles
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(itstool) path: figure/desc
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(no translation yet)
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Located in
C/color-whatisspace.page:49
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498.
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AdobeRGB is frequently used as an <em>editing space</em>. It can encode more colors than sRGB, which means you can change colors in a photograph without worrying too much that the most vivid colors are being clipped or the blacks crushed.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:62
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500.
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Now, if ProPhoto is clearly better, why don't we use it for everything? The answer is to do with <em>quantization</em>. If you only have 8 bits (256 levels) to encode each channel, then a larger range is going to have bigger steps between each value.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:75
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501.
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Bigger steps mean a larger error between the captured color and the stored color, and for some colors this is a big problem. It turns out that key colors, like skin colors are very important, and even small errors will make untrained viewers notice that something in a photograph looks wrong.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:81
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502.
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Of course, using a 16 bit image is going to leave many more steps and a much smaller quantization error, but this doubles the size of each image file. Most content in existence today is 8bpp, i.e. 8 bits-per-pixel.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:88
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503.
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Color management is a process for converting from one color space to another, where a color space can be a well known defined space like sRGB, or a custom space such as your monitor or printer profile.
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(itstool) path: page/p
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(no translation yet)
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Located in
C/color-whatisspace.page:94
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504.
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external ref='figures/color-average.png' md5='9189963fdd14f11f0685a9ef2196279b'
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(itstool) path: page/media
This is a reference to an external file such as an image or video. When
the file changes, the md5 hash will change to let you know you need to
update your localized copy. The msgstr is not used at all. Set it to
whatever you like once you have updated your copy of the file.
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(no translation yet)
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| In Ubuntu: |
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(not translated yet)
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Located in
C/color-why-calibrate.page:25
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