Search found 12670 matches

by snibgo
2020-02-18T16:45:11-07:00
Forum: Users
Topic: convert: NoImagesDefined
Replies: 2
Views: 46

Re: convert: NoImagesDefined

C:\Users\henri\Desktop\ImageMagick-7.0.9-Q16>convert ... I expect that's the problem. You installed ImageMagick to a directory, but then moved that directory to your desktop, and now IM can't find its own files. If you really want IM to reside in a directory on your desktop, re-install IM and give ...
by snibgo
2020-02-18T15:24:45-07:00
Forum: Developers
Topic: Minor webpage documentation clarification for HDRI
Replies: 6
Views: 119

Re: Minor webpage documentation clarification for HDRI

Skygaze wrote:Suggested: "Building ImageMagick source for Windows requires a modern version of Microsoft Visual Studio IDE (free)"
I suggest changing "requires" to "can be done with". I've been building IM on Windows with GNU tools for years, without "requiring" MS VS.
by snibgo
2020-02-18T10:35:03-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

If you double the size, you effectively get one more bit of precision, so 9 instead of 8. If you supersample by a factor of 8, that is an extra 3 bits, so 11 instead of 8. In my link I show we generally need at least 8 more bits, so 16 instead of 8. To get this by supersampling, you would need to re...
by snibgo
2020-02-18T09:03:20-07:00
Forum: Users
Topic: white bleeding in pdf files
Replies: 1
Views: 41

Re: white bleeding in pdf files

What is your IM command? With Adobe Acrobat Reader, I can't see a thin white line on your PDF.
by snibgo
2020-02-18T08:53:47-07:00
Forum: Users
Topic: EXR to DDS?
Replies: 3
Views: 90

Re: EXR to DDS?

Sorry, I know nothing about DDS formats. See the DDS entry in https://www.imagemagick.org/script/formats.php . I suspect DDS is integer-only.
by snibgo
2020-02-18T07:38:23-07:00
Forum: Users
Topic: EXR to DDS?
Replies: 3
Views: 90

Re: EXR to DDS?

I suppose your DDS "R16G16B16A16" is an integer format. EXR HDR images are high dynamic range, which means some values are greater than the usual QuantumRange (65535 or whatever). Those values can't be put in an integer file format. Of course, the values can be reduced so they are no longer greater ...
by snibgo
2020-02-18T07:27:00-07:00
Forum: Developers
Topic: Problem with IM version TIF to PNG
Replies: 2
Views: 59

Re: Problem with IM version TIF to PNG

Please upload a sample input and output to somewhere, and paste links here.
by snibgo
2020-02-17T19:29:15-07:00
Forum: Digital Image Processing
Topic: Any recom for HDR (6x2EV) and batch proc?
Replies: 13
Views: 497

Re: Any recom for HDR (6x2EV) and batch proc?

Hmmm, a bit puzzled... saturated sensels output gives me MIN=1.30025e+08 MAX=1.03037e+09 SAT_PC=100 which in a way makes sense since at 14-bit (Canon CR2) I am asking for pixels brighter than 16383. But min 1.30025e+08 ! You are doing something wrong. dcraw can make 8-bit or 16-bit integer files. T...
by snibgo
2020-02-17T15:16:51-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

See also Straightening horizons: How much precision?. I did those tests with IM v6. They show that Q8 integer is really horrible, Q16 integer or HDRI is better, but Q32 is best for that example.
by snibgo
2020-02-17T14:30:29-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

With Inkscape 1.0beta2 16 bit export leading to the same artifacts, this likely means that the gradients aren't actually rendered at 16 bits, right? Possibly. IM "identify -verbose" will tell you whether the map image has more than 8 significant bits. But that wouldn't prove the bits are accurate ....
by snibgo
2020-02-17T13:57:52-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

I opened the front map in GIMP, changed the precision from 8 bits to 16 bits and applied Gaussian blur, radius 2. You can do those operations in IM. I should have checked for that obvious problem. Distortion maps should never be 8-bit precision. If they are, quantisation gives an expected error of ...
by snibgo
2020-02-17T12:42:50-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

perspector wrote:Without downsampling to map-size first, this happens: ...
I suggest you upsample the map, then distort, then downsample as needed.

As the map comes from a vector SVG, you should tell IM to make a larger PNG. I suppose this is the "--export-dpi" option.
by snibgo
2020-02-17T12:20:25-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

Yes, as Fred says, if you can distort without using a map, the result will be better, without having to supersample.
by snibgo
2020-02-17T11:55:53-07:00
Forum: Users
Topic: Jaggy results with using maps for perspective transform
Replies: 17
Views: 316

Re: Jaggy results with using maps for perspective transform

You are generating a map from an SVG, then downsampling an image to that size, and distorting. Is that right? Is the SVG file just wrapper for a raster image, or a genuine vector image? Instead of downsampling then distorting, you will get a better result if you distort then downsample. The result m...
by snibgo
2020-02-17T11:33:06-07:00
Forum: Developers
Topic: Minor webpage documentation clarification for HDRI
Replies: 6
Views: 119

Re: Minor webpage documentation clarification for HDRI

Yes, please do. The official documentation is on github so you can pull or push requests or whatever it is, if you know how to (I don't).

Otherwise, put suggestions here, with the URLs of the web pages.