Search found 12163 matches

by snibgo
2013-05-13T15:44:43-07:00
Forum: Bugs
Topic: possible bug gradient with transparency IM 6.8.5.6 Q16 Mac
Replies: 21
Views: 10178

Re: possible bug gradient with transparency IM 6.8.5.6 Q16 M

convert -size 1x256 gradient:"rgba(0,0,0,0)-rgba(255,0,0,1)" -rotate 90 -scale 256x50! -alpha off 1grad_aoff.tiff Confimed that this gives solid red, apart from black strip down right side, tested on v6.7.9 and 6.8.0 to 6.8.5, on Windows 7. I think the result should be identical to ... co...
by snibgo
2013-05-13T11:49:34-07:00
Forum: Users
Topic: How to use edge detection to count number of edges / objects
Replies: 1
Views: 2956

Re: How to use edge detection to count number of edges / obj

If you can distinguish them, you can count them.

It's difficult to say more than that without a specific example. Can you supply a relevant image?
by snibgo
2013-05-12T21:38:26-07:00
Forum: Users
Topic: Request for output from automated operators
Replies: 11
Views: 7728

Re: Request for output from automated operators

Yes, I want to use Anthony's first method: from a representative frame (or a number of representative frames appended), do an automatic operation, then repeat the equivalent operation with identical parameters on all the frames in a clip. The only operation I use that IM doesn't give me useful infor...
by snibgo
2013-05-11T02:37:29-07:00
Forum: Users
Topic: Request for output from automated operators
Replies: 11
Views: 7728

Re: Request for output from automated operators

Well spotted, thanks!
by snibgo
2013-05-10T05:44:25-07:00
Forum: Users
Topic: Channels not a single grayscale?
Replies: 7
Views: 9166

Re: Channels not a single grayscale?

So your output has three channels, but they are equal at each pixel? For me, the output has a single channel. This is for both v6.7.9 and v6.8.5. However, these versions give slightly different results because of how IM treated greyscale files between those versions. I suspect the v6.8.5 gives the s...
by snibgo
2013-05-10T04:08:09-07:00
Forum: Users
Topic: Need .exr support for simple composite of tiled render
Replies: 13
Views: 9128

Re: Need .exr support for simple composite of tiled render

Sorry, I don't know the definitive answer. I think you need to recompile. However, the dynamic version uses DLL files, so maybe if you get hold of the appropriate DLL file (perhaps named CORE_RL_exr_.dll), that's all you need. Even then, you might need to tweak the delegates file.
by snibgo
2013-05-10T04:01:10-07:00
Forum: Users
Topic: Channels not a single grayscale?
Replies: 7
Views: 9166

Re: Channels not a single grayscale?

You are selecting one channel, with "-channel R". If you want all channels, don't select just one.

Code: Select all

convert rose: v.tif
should create a tiff file with three greyscale images, representing the R, G and B channels of rose.
by snibgo
2013-05-09T23:26:59-07:00
Forum: Users
Topic: Request for output from automated operators
Replies: 11
Views: 7728

Re: Request for output from automated operators

Code: Select all

identify -format "%[fx:log(mean)/log(0.5)]" rose:
That seems to be it. I get zero difference when using this for "-gamma", compared to using "-auto-gamma". Thanks.
by snibgo
2013-05-09T23:10:30-07:00
Forum: Users
Topic: Request for output from automated operators
Replies: 11
Views: 7728

Re: Request for output from automated operators

Thanks Fred. For contrast-stretch, I currently use an external program that reads a histogram file and spits out the appropriate level operator for given thresholds. I had brain-fade, and had forgotten min, max and %P%O. Can I query your gamma formula? identify -format "%[fx:mean] %[fx:log(0.5/...
by snibgo
2013-05-09T21:47:43-07:00
Forum: Users
Topic: Request for output from automated operators
Replies: 11
Views: 7728

Request for output from automated operators

When processing video frames, I often want to apply the same processing to all the frames in one clip. IM has automated versions of manual operators (eg "-auto-level" and "-level"). Using the automated version on all frames generally gives a jerky result. I would like to use the ...
by snibgo
2013-05-09T18:59:51-07:00
Forum: Users
Topic: Stripping color profiles from images for use on the web?
Replies: 3
Views: 3059

Re: Stripping color profiles from images for use on the web?

If you merely strip the profile, browsers will assume the image is sRGB. But the image might not have been sRGB.

It might be safer to:

Code: Select all

convert {blah blah} -profile sRGB.icc -strip outfile
by snibgo
2013-05-09T04:41:41-07:00
Forum: Users
Topic: Need .exr support for simple composite of tiled render
Replies: 13
Views: 9128

Re: Need .exr support for simple composite of tiled render

I tried "convert memorial.exr m.png" with IM v6.7.9, 6.8.0, 6.8.1, 6.8.2, 6.8.3, 6.8.4 and 6.8.5. Sorry, no luck.
by snibgo
2013-05-09T04:01:41-07:00
Forum: Users
Topic: Need .exr support for simple composite of tiled render
Replies: 13
Views: 9128

Re: Need .exr support for simple composite of tiled render

"identify -list format" doesn't list exr. Ahh, that's interesting. The file I created, r.exr, seems to be a PPM file, and starts with: P6 70 46 255 I know nothing about exr, but that seems unlikely. More testing revels this behaviour happens for any random collection of junk characters as ...
by snibgo
2013-05-09T01:47:54-07:00
Forum: Users
Topic: Need .exr support for simple composite of tiled render
Replies: 13
Views: 9128

Re: Need .exr support for simple composite of tiled render

I run Windows 7. The pre-compiled IM v6.8.5 seems to handle EXR. At any rate, the following work (which doesn't prove it is correct, of course):

Code: Select all

convert rose: r.exr
convert r.exr p.png
by snibgo
2013-05-08T13:23:50-07:00
Forum: Users
Topic: Add a pattern to a b/w image
Replies: 4
Views: 3913

Re: Add a pattern to a b/w image

Yes, the equivalent of selections in IM is masks. For shrinking or expanding, the morphology operators are very useful. For some cases, blur and threshold works well.