CONTENT
Arteffect has in it`s basic version the format IFF-ILBM, IFF-RGB8, JPEG, TIFF, PING, PCX, BMP, TARGA
for saving. With the expansion for Loading/Saving you can improve your Arteffect. We explain only the important
saving format. GIF and Animation GIF find their way in this lesson because they are the most used Internet graphicsformat.
Arteffect can save GIF only with the expansion. With Arteffect you can easely change your pictures from one format
into another one. For this use the function Saving as.... |
If you use the Demo-Version of Arteffect, the saving function is disabled. |
|
1. Graphicformat GIF
The "Graphics Interchange Format", which CompuServe developed 1987 for the Internet, is a pure 256 Colour
(8-bit) format. It is used for small and medium sized pictures. It is better with small pictures than JPEG. Even
text stay sharp enough to be read, because GIF do not smooth the picture like JPEG. If you have your own homepage
or you plan one, GIF is your format.
GIF has some disadvantages. Do not use it for big sized pictures ( about >400*400 pixel), because the compression
algrorithm delivers a big data ( 2-3 times bigger than JPEG does ). And GIF is unuseable for True-/Hi-Color pictures.
As said before, it is a 256 Color (8-bit) format, not a 16/24-bit format like JPEG. |
|
2. Graphicformat Animation GIF
Animation GIF is nothing more than a sequence of single GIF pictures, which
are played constantly. If you try to get a smooth sequence, you normaly need >15 pictures. These pictures are
played in a permanent replay. To trick the eye you need 25 pictures per secound. At this frequence (50 Hz) the
eye can not discern the single pictures. For a Loop-Animation your end-picture must be the start-picture. For a
Pingpong-Animation it does not matter, because the Animation is played like a Pingpong ball. |
|
3. Graphicformat JPEG
The "Joint
Photographic Experts Group" brought 1986 the JPEG-Compression on the market. This standard is known today
as JPEG File Interchange Format (JFIF) on the Internet. With JPEG you have to decide, if you want a high quality
picture or a high compressed, small sized picture for storage. You can not have both. With JPEG you loose quality
compared to the original picture - every time. With ArtEffects JEPG-savingmodul you are question for the QUALITY and SMOOTHING. With high quality (max.
100 %) your picture has a good finish, but its size is even big. With less quality and high compression it is inverse.
With high compression you got the JPEG typical block-picture faults (called Artefacts), which mar the picture.
A good messure for the compression is 75% and for smoothing 40% will be enough. |
If you use the Demo-Version of Arteffect, the saving function is disabled. |
|
4. Graphicformat PNG
The "Portable Network Graphics" Format was developed
in act with the trouble of the royalty for GIF. By the way it closed a gap, GIF had left. Now it is possible to
store a picture with colourdepth from 1 to 48 Bit lossless. You can use PNG for your Hi-/Truecolor picture, but
for storage (small sized pictures) JPEG is better than PNG. PNG is much faster to load by browsers than GIF or
JPEG of same size.
PNG`s disadvantage is, that it stores only one picture per data. So, no Animation is supported. For this you need
MNG (Multiple-Image Network Graphics), but it is still in development - no release time in sight. And today`s browser
are leaking real PNG support. Voyager in it`s new version is the first Amiga-browser, who is able to show PNG. |