I have just been reading regarding the Trace Bitmap utility in Inscape.

I have a beginers question.

If someone uploads a Bitmap into Inscape, why not just use it, rather than use Trace? As you can see,I am missing something.

What is the advantage of using Trace?

Thanks

Ps. I have asked at this point because it make it easier for me to learn.

You have to understand the difference between raster/bitmap graphics and vector graphics, which is fairly well explained on Wikipedia. You can also envision bitmap as painting a brick wall using a color per brick, while vector graphics are instructions to move the paintbrush over the wall.

Of course, when the image is really complex (photography) a bitmap is better, but most simple images (logo, text, cartoons...) are better described as vectors.

I do understand that vectors allow expansion without pixelation. Is this the only reason people use Trace Bitmap, so that they can expand the images existing in original bitmaps without loss of quality?

Ps. I know that raster is concerned with bitmaps, and vectors with mathematical expressions

Expand is not everything. All geometric transforms that do not map pixel for pixel(*) will introduce some blur in bitmap graphics. In the image below, the very same perspective transform has been applied to a bitmap and to the equivalent path (which is then filled). The G gets blurry because it is expanded, but the P which is called down also becomes slightly blurry. No such blur in the path version.



(*) About all, except, move, flip, and rotation by a multiple of 90°

Inkscape's native file SVG is a vector format although it can be a container of raster image data. Bitmap Trace should be used when you plan to alter that data. If you're simply adding a PNG or JPEG to a static SVG canvas Bitmap Trace is not required.

I've attached a SVG that contains vector and raster data. I opened this JPG in Inkscape (the raster data was not altered) and added the stars and text. The image looks good because it still has all the original raster data in a static view. When zooming in or out the vector data stays crisp, only the raster data is slightly distorted. In this case Bitmap Trace was not required because the result is acceptable. If I needed to alter the raster image data (filters, color, etc.) or canvas size later I would have considered using Bitmap Trace first. It's case by case whether you need to use Bitmap Trace or not when adding raster images in Inkscape.

Thank you,

Yes, I see what you mean when zooming. I can zoon using the wheel on the mouse. Is there a button that allows continous zooming/reduction? I can't see one!

I get the impression that 'at the end of the day' Trace/or not, or even using Inkscape itself is all dependent on the quality of the final image, after zooming or transforations (ref. Ofnuts).

Best wishes.

A

Ok,

I see what you mean, I need to consider expansions and transforms and the effects of blur in bitmaps vs better defined vector constructions.