Editing jpegs inside a PDF file, using Gimp or other graphics programs

[Torakaze-222]

Hi,

I read someplace here or over on Zealot, about how you can open a PDF file in Photoshop or Gimp and edit the jpegs to do a recolor. Or to resize parts.

So opened a PDF in Gimp and proceeded to recolor. But Gimp had totally messed up the line detail, when it opened the image. I'm not sure but I think it's because Gimp is raster based.

Is there a downloadable graphics program that will open PDF files without messing up the line thickness and sharpness?

I think a vector based one will work, not sure. My limited understanding of vector based graphics is that the lines and patterns of a computer drawn graphic are stored as programmed paths (math) and it redraws them whenever you scale up or scale down. So the lines are always sharp and proper line thickness is maintained. And raster based just stores the image as a flat surface only broken up into pixels, like a mosaic tile floor. And any resizing, means the program randomly decides which pixels to throw away. So image sharpness and detail is lost anytime the image is resized smaller, and up sizing an image just makes the pixel noise more noticable.

Was trying to recolor Magnus Morck's Albemarle kit with the color pallet from CT Ertz's Tennessee kit. The casement on the Albemarle was really looking good with the gray that CT Ertz uses in his ironclad kits, until I noticed Gimp had skewed the proportions of the detail lines and the rivet detail was messed up, and off center, when it looks all perfectly centered in the PDF and hardcopy printed from the PDF in Acrobat Reader.

Thanks for any help with this

Thanks,
Ledo

[legion]

Try increasing the dpi when you import the pdf? From experience with my copy of PS7 i get a popup saying how much dpi it needs/wants. Standard is 72 dpi, try 200 or more. You will however get huge filesizes.

[RyanShort]

Try using Inkscape.

Ryan

[Stev0]

Originally Posted by RyanShort

Try using Inkscape.

Ryan

FAQ - Inkscape Wiki

What formats can Inkscape import/export?

Inkscape natively supports opening or importing SVG, SVGZ (gzipped SVG), PDF, and AI (Adobe Illustrator) format

[Torakaze-222]

Thanks much for the advice. Will try to open at larger DPI and download Inkscape too.

[SchizophrenicMC]

I zoom into the desired scale (For example, 700% for my current project), and use the Snipping Tool included in Windows Vista (The old screencap trick works just as well), and import several, overlapping images. It's time-consuming but it gets results. Then, I align each image so the part is whole again, and begin framing each part out by copying an 8.5x11" selection from each section, overlapping an inch always. Better to overlap more so you can remove excess later.

In the end, it can take hours to finish a large part, and as such, I only have the wings and top of the fuselage completely set out. Since I export all the images as PNGs, they're saved in perfect quality, albeit bitmap. I can just print from there and I've got my up (or down) scale.

It's more work, but the results are pretty good for someone too lazy to learn a new program's nuances.

[georgerutherford1861]

I downloaded Inkscape a month ago due to (I think) a previous recommendation by Ryan on the forums here. It has a bit of a learning curve, but the online tutorials help and it has worked very well for me so far. I've done a personal repaint of a 46 Squadron Camel and am now working on another personal repaint of a Jasta 11 Albatros DV. I'm still learning quite a bit (learned to use the clip function yesterday, great for getting textures and clipping them to the proper size of the piece you're working on), and it is doing quite well.

Doug

[hornswoggler]

Torakaze-222

Pdf-files are meant to give reliable printouts across different platforms ( Windows, Mac, ...). This goal is achieved by packaging text and graphics of diverese formats into a special container file that does the talking to the printer to make sure everything is printed in the right place, size and color. The pdf file does not really convert jepg graphics that was placed into it into vector graphics.

Thus, if the original graphics that went into the pdf was jpeg, as you claim, (or any other bitmap) you want to edit it with a program that is meant to edit bitmaps. Photoshop, Gimp and the likes are good choices.

Inkscape on the other hand is a vectorgraphics program (like Illustrator and Corel Draw) which is meant to create and edit vector graphics - not bitmaps -duh! Inkscape cannot be used to change colors of a bitmap directly.
Inkscape can import bitmaps as background pictures though. This opens up an option for a tedious workaround. Import the bitmap as a background picture and then trace it. The tracing is best done by hand. Do not use the automatic tracing routine - it requires far too much clean up afterwards. Once you have redrawn the whole picture as vector graphics - all parts are no geometrically defined objects- , you can assign fill and line colors. This is hard work, even when you are proficient in Inkscape. It is only worthwhile if you want to drastically scale-up the original kit because once in vectorgraphics you can scale to your hearts content without messing with the quality of the output. However, keep in mind that good kit design takes the thickness of the cardstock into account. While vector graphics allows you to scale the output without loosing print quality, after scaling the parts may not fit very well any more unless you scale the thickness of the cardstock too.

If you just want to change the colors stay with Gimp!

Bernhard

[SchizophrenicMC]

My method's much more labor-intensive, but it's easier to learn. :P