Kapitel 6. Få billeder ud af GIMP

Kapitel 6. Få billeder ud af GIMP
	Del II. Hvordan bliver jeg en rigtig GIMP-guru?

Indholdsfortegnelse

1.1. Gem/eksportér billeder
1.2. Filformater

2. Forbered dine billeder til nettet

2.1. Billeder med et optimalt forhold mellem størrelse og kvalitet
2.2. Reducér filstørrelsen endnu mere
2.3. Gem billeder med gennemsigtighed

1. Filer

GIMP is capable of reading and writing a large variety of graphics file formats. With the exception of GIMP's native XCF file format, file handling is done by plug-ins. This makes it relatively easy to extend GIMP to support new file types when the need arises.

1.1. Gem/eksportér billeder

	Bemærk
When you open an image, let's say in JPG or PNG file format, it is imported into GIMP's own XCF format, as a new project. For example, a “sunflower.png” image will be loaded as “[sunflower] (imported)-1.0 (indexed color, 1 layer)”. The leading asterisk indicates that this file has been changed. This image can be saved as “sunflower.xcf” by using the Save* command. If you need your image in another format, you should use the Export command.

Bemærk

When you open an image, let's say in JPG or PNG file format, it is imported into GIMP's own XCF format, as a new project.

For example, a “sunflower.png” image will be loaded as “*[sunflower] (imported)-1.0 (indexed color, 1 layer)”. The leading asterisk indicates that this file has been changed. This image can be saved as “sunflower.xcf” by using the Save command. If you need your image in another format, you should use the Export command.

When you are finished working with an image, you will save the results. In fact, it is often a good idea to save at intermediate stages too. GIMP is a pretty robust program, but on rare occasions crashes have happened.

GIMP's native format XCF is special. It is the only format that can store everything about an image (with the exception of “undo” information). This is the reason that saving can only be done in this format. It makes the XCF format especially suited for storing intermediate results, and for saving images to be re-opened later in GIMP.

XCF files are not readable by most other programs that display images. Once you have finished editing your image, you can export it to the format of your choice. GIMP supports a wide range of formats. Most file formats that can be imported, can also be used for exporting.

1.2. Filformater

There are several commands for saving and exporting images. They are listed in the section covering the File Menu. More information on how to use them can be found there.

GIMP lader dig eksportere de billeder, du laver, til en række formater. Det er vigtigt at være opmærksom på, at det eneste format, som kan gemme al information om et billede inkl. lag, gennemsigtighed osv., er GIMPs eget XCF-format. Alle andre formater bevarer nogle billedegenskaber og mister andre. Det er dit eget ansvar at forstå egenskaberne af det format, du vælger.

Når et billede eksporteres, ændrer det ikke selve billedet, så du mister ikke noget ved at eksportere. Se Eksportér fil.

	Bemærk
Når du lukker et billede (f.eks. ved at afslutte GIMP), bliver du advaret, hvis billedet er “snavset”, dvs. hvis det er blevet ændret uden efterfølgende at blive gemt (der er en stjerne foran billedets navn). Figur 6.1. Advarsel ved lukning Saving an image in GIMP's native format XCF will cause the image to be considered "not dirty". On the contrary, exporting an image will not change it to "not dirty", because GIMP can't know for sure that no image information will be lost.

Bemærk

Når du lukker et billede (f.eks. ved at afslutte GIMP), bliver du advaret, hvis billedet er “snavset”, dvs. hvis det er blevet ændret uden efterfølgende at blive gemt (der er en stjerne foran billedets navn).

Figur 6.1. Advarsel ved lukning

Saving an image in GIMP's native format XCF will cause the image to be considered "not dirty". On the contrary, exporting an image will not change it to "not dirty", because GIMP can't know for sure that no image information will be lost.