SCALING RASTER IMAGES

[cfee]

On previous releases of ACAD, I was able to select the "pasted" raster image as one "entity", and do some things like assigning it to a particular layer and locking that layer so someone else couldn't move it, or I could insert it as a block with uneven scale factors, once I had determined the absolute distortion, and then could re-scale it to correct dimensions, or even use the scale command, select the inserted raster image as a single ACAD entity, and adjust its size (scale) as a detail in the drawing. This allowed us to use raster-imaged snippets of drawings where we wanted them, without having to convert them to vectors. Setting "draw-order" was another IMPORTANT function I seem to have lost, as the image repeatedly re-asserts itself "on-top", even after repeated re-sets to "on-bottom".

In the version of ACAD I'm using on my new job (2002) I am not able to "scale", change layer, or any of a handfull of manipulations I used to be able to do in earlier versions (r12-14), using CONVENTIONAL ACAD commands.

Conventional grip-dragging is cumbersom for these tasks, and so does NOT represent an appropriate workaround, and does NOTHING toward selecting the raster image entity for placement on a "locked" layer.

I'm looking for settings Im not aware of or other steps to make these images useful for my new boss.

Tks-
C. Fee

 

[kpetursson]

I use 2002 with raster graphics without any problems.

how are you inserting them into your drawing?

I use from the menu "Insert" -> "Raster Image"

if you copy and paste from another program autoCAD inserts it as an OLE object. Non of the usual autoCAD commands work with OLE objects.

Hope this helps.

Kevin Petursson

 

[TCARPENTER]

Hi cfee,

Just a couple of thoughts for you, make sure the layer the image is inserted on is not already locked, and when you select the image, you need to select its border (see IMAGEFRAME below). Here's a couple of other items for you:

[ul]Commands
[li]IMAGE Manages images[/li]
[li]IMAGEADJUST Controls the image display of the brightness, contrast, and fade values of images[/li]
[li]IMAGEATTACH Attaches a new image to the current drawing[/li]
[li]IMAGECLIP Creates new clipping boundaries for an image object[/li]
[li]IMAGEFRAME Controls whether image frames are displayed or hidden from view[/li]
[li]IMAGEQUALITY Controls the display quality of images[/li]
[li]TRANSPARENCY Controls whether background pixels in an image are transparent or opaque[/li]
[/ul]

[ul]System Variables
[li]IMAGEHLT Controls whether the entire raster image or only the raster image frame is highlighted[/li]
[/ul]

 

[cfee]

kpetursson -
Thanks for your reply!
As in earlier versions (mentioned) I am ^V "Pasting" the image. This brings it in as a METAFILE, which retains things like resolution and vector info (a great way to get vector graphics out to "non-compatible" programs, but more on that later.

This quality is CRITICAL to accurate representations of the drawing data, and is far superior to basic raster formats like BMP, which captures pixel data down to the highest desnity the raster editor can deliver (for instance, 24-bit in Windows Paint, and far worse in JPG.

In earlier versions of ACAD, you could pre-set the necessary variables, and your "Paste" would take. Then you could grab the border, and re-scale, remove to a locked layer, set draworder, etc.

Nowadays, with newer ACAD, this may no longer be available except for manipulating "imported" raster images. Workable, but the final result is FAR INFERIOR, as resolution scalability available with vector metafiles is = to ACAD in "zoomability"...

With this additional info, any suggestions?

Thanks...

TCARPENTER-

These vatriables are going to be VERY helpful to me in my efforts to get this project out for my boss. Thanks.
Still- Any thoughts on the above?

Thanks Both-
C. Fee

 

[TCARPENTER]

Hi C.

Metafiles are a different ball of wax. For this you'll have to use the WMFIN command and you'll use the WMFOPTS command to control WMFIN variables. But if your files are not a metafile format, WMFIN won't import them.

If you have a lot of raster images you need to bring in, you may want to check out WinTopo. You can get a free version of this which will convert bitmaps, jpegs, etc to DXF files AutoCAD will bring in as vector information.

HTH
Todd