Search found 457 matches

by GreenKoopa
2013-08-13T15:39:50-07:00
Forum: Users
Topic: how -trim images with black border and black background
Replies: 17
Views: 18755

Re: how -trim images with black border and black background

Is this what you want? : create an example image convert rose: -background black -gravity center -extent 100x100 in.png : Calculate trim, but only 10 pixels off max convert in.png ^ ( +clone -shave 10x10 -evaluate Set 100%% ) -gravity center -composite ^ -trim -format "%%wx%%h%%X%%Y" info: --- Outpu...
by GreenKoopa
2013-08-13T09:01:51-07:00
Forum: Users
Topic: Metallic effect
Replies: 21
Views: 26564

Re: Metallic effect

Step 8, the bump map , is the only potential hang-up. Gimp's documentation describes it here . Hopefully someone has an easy answer for this narrower problem. http://docs.gimp.org/en/images/filters/examples/example-map-bumpmap.png Steps 1-4 are single operations. Steps 5-7 are a little harder but no...
by GreenKoopa
2013-08-12T17:43:23-07:00
Forum: Users
Topic: Background removal
Replies: 8
Views: 3794

Re: Background removal

As my test showed, it is exactly the original minus black. While I preserve hue (this process will work for any color), of course brightness has increased. That is what removing black does. The question was how much black you wanted removed. I removed it all, which I thought was too much but this is...
by GreenKoopa
2013-08-12T01:43:22-07:00
Forum: Users
Topic: Background removal
Replies: 8
Views: 3794

Re: Background removal

If you know that the background is black, any result should get you back to the original by placing it on a black background. The math for transparency is simple, but it doesn't yield a single solution. For example, your source image composed over a black background will yield the same image since i...
by GreenKoopa
2013-08-11T22:09:02-07:00
Forum: Users
Topic: Question: is rotating by 90, 180, 270 destructive
Replies: 10
Views: 11983

Re: Question: is rotating by 90, 180, 270 destructive

I am using the latest version of jpegtran (Windows .exe) and it seems to rotate OK, I think (?), but loses the icc profile in the process Try -copy all to keep profiles, etc. convert rose: rose.jpg rose is 70x46, which is not divisible by a 8 or 16 pixel jpeg block size. This makes it a bad test ca...
by GreenKoopa
2013-08-11T08:08:44-07:00
Forum: Users
Topic: Reversed Bilinear Distortion + Crop
Replies: 4
Views: 3315

Re: Reversed Bilinear Distortion + Crop

Welcome. Please share the exact command you tried. Before and after images may also help.

In that usage example, the input and output canvas sizes are the same. Is this what you are seeing, and what you want?
by GreenKoopa
2013-08-11T08:02:19-07:00
Forum: Users
Topic: Question: is rotating by 90, 180, 270 destructive
Replies: 10
Views: 11983

Re: Question: is rotating by 90, 180, 270 destructive

There is no quality loss when you begin and end with a lossless format. If you use a lossy format, such as jpeg, there can be loss simply by loading and saving an image. This is true for most image processing applications. A jpeg image that meets certain requirements can be rotated losslessly using ...
by GreenKoopa
2013-08-09T07:31:31-07:00
Forum: Users
Topic: Need help with recreate canvas from multiple images + coords
Replies: 8
Views: 4827

Re: Need help with recreate canvas from multiple images + co

You said there are many approaches, I really would like to know the main differences between them and why you chose this one. I think snibgo's approach gives a good result, is easy to understand, and is easy to modify as you need. -distort is capable scaling without the needing a separate -resize. ...
by GreenKoopa
2013-08-06T15:00:46-07:00
Forum: Users
Topic: 8-bit raw little-endian to color PNG
Replies: 15
Views: 6675

Re: 8-bit raw little-endian to color PNG

ImageMagick can import raw. IM delegates Bayer processing to dcraw. Alternatively dcraw can be used directly as a first step, and IM used for later steps.
http://www.imagemagick.org/Usage/formats/#crw
by GreenKoopa
2013-08-06T05:24:15-07:00
Forum: Users
Topic: bakground debris
Replies: 6
Views: 3743

Re: bakground debris

In IM selection is done by creating masks. So a fuzzy select / magic wand tool is really the same as a bucket / flood fill tool. IM has two fill tools: -floodfill and -draw floodfill. +level 0,98% Makes an image slightly darker. Now 98% gray is the closest color to white. -fill white This sets the c...
by GreenKoopa
2013-08-06T04:46:18-07:00
Forum: Users
Topic: bakground debris
Replies: 6
Views: 3743

Re: bakground debris

Thanks, seeing helps. Your image is not pure black and white, so I included a fuzz factor. One solution: convert mask.png +level 0,98% -fill white -fuzz 50% -floodfill +640+960 white -threshold 99% mask_new.png If you are using a Windows batch file, don't forget to escape the %s (otherwise it will f...
by GreenKoopa
2013-08-06T04:10:58-07:00
Forum: Users
Topic: bakground debris
Replies: 6
Views: 3743

Re: bakground debris

Nik wrote: I would like to select the white area of the image, based upon the centre of the image.
Pure white or near white? A connected area that includes the center? Like a fuzzy select wand tool? Seeing the image may help.
by GreenKoopa
2013-08-05T10:45:59-07:00
Forum: Users
Topic: Need help on the resize and -composite in convert
Replies: 6
Views: 5774

Re: Need help on the resize and -composite in convert

A space is required around every ( and ) .
by GreenKoopa
2013-08-05T00:56:38-07:00
Forum: Users
Topic: Need help on the resize and -composite in convert
Replies: 6
Views: 5774

Re: Need help on the resize and -composite in convert

Welcome. Platform and version?
by GreenKoopa
2013-08-04T23:52:32-07:00
Forum: Users
Topic: -distort
Replies: 6
Views: 4217

Re: -distort

I liked using distort:scale because it allowed me to specify my viewport size and offset in before-scaling terms. I would determine my area of interest using Gimp, say 3696x2464+580+496. Given an image and this geometry, I used IM to output the area down-sampled to several sizes. A much simplified e...