plotting Color jpeg files black and white

[dontejalynx]

I'm having an issue plotting Color jpeg files black and white. My ctb file has all colors except 250-254 set to black, but the image still plots in color. The files are pdf's that I open in Bluebeam and then saveas to jpeg. I'm plotted to a Canon IPF710 and I have the plot w/ plot styles checked.

[cadtag]

Yes, that's the way it works with jpeg. The jpeg is a truecolor object, and the colors in it do not match up to autocad's ACI colors.

What you need to do is convert that color jpeg to a grayscale image, and then plot.,

Now, to get a bit more involved -- what exactly do the images represent? lines and text, or real imagery? If the former, instead of jpeg, use TIFF. If you create that as a B/W bitonal tif, then you can use transparency on it, and the non-transparent pixels will take on the display color (and be controlled by the ctb)

[rkmcswain]

Raster images are not subject to plot styles.
The easiest solution may be to convert the image (or a copy) to grayscale using a raster image application, then update the reference in AutoCAD.

[dontejalynx]

Thanks. My resolution was to open the pdf in Bluebeam, saveas a tiff file and then open the file in Microsoft Paint; click Image - Attributes - change to black and white and save it.

[irneb]

Or you could use one of the other PDF virtual printers, most of them have the ability to save directly to a JPG (or other image format). The nice thing with this is the image adheres to your CTB settings (unlike ACad's own image plotter drivers).