Search found 11220 matches

by snibgo
2019-02-18T10:55:16-07:00
Forum: Users
Topic: Alpha channel gets removed from grayscale image with IM 7.x
Replies: 3
Views: 77

Re: Alpha channel gets removed from grayscale image with IM 7.x

I don't understand the problem. The command has "-alpha off". This removes the alpha channel. Why is this a problem?
by snibgo
2019-02-18T10:45:54-07:00
Forum: Users
Topic: Montage and the crop the output in one command?
Replies: 6
Views: 130

Re: Montage and the crop the output in one command?

As Fred says, and the "convert" can do whatever cropping or other processing is required. However as IM v7 is used, I suggest "magick montage" and "magick" instead of "montage" and "convert".
by snibgo
2019-02-18T08:35:00-07:00
Forum: Users
Topic: converting bmp to grayscale png
Replies: 2
Views: 56

Re: converting bmp to grayscale png

The metadata in your BMP says the image takes zero bytes in the file. This is clearly wrong, and IM warns you about this. But it is just a warning, and the result should be okay.
by snibgo
2019-02-18T03:05:41-07:00
Forum: Users
Topic: Blurring huge images/processing time
Replies: 1
Views: 40

Re: Blurring huge images/processing time

Another option is to resize down, then back up. I suppose the problem is that you don't have enough memory, so IM needs to use disk. GIF is 8-bit, so you might use IM Q8 which has half the memory use of Q16. In addition, don't use HDRI. (Q8 non-HDRI will give slightly lower quality, but I doubt this...
by snibgo
2019-02-17T14:32:48-07:00
Forum: Users
Topic: Apply shadow to rectangle with alpha
Replies: 10
Views: 197

Re: Apply shadow to rectangle with alpha

For v7, I suggest you use "magick", not "convert" or "composite"

You could do all the work in a single "magick" command, with no intermediate files.
by snibgo
2019-02-17T13:16:36-07:00
Forum: Bugs
Topic: Documentation page vanished
Replies: 2
Views: 60

Re: Documentation page vanished

It was redirecting to a generic ImageMagick page, but now it works correctly. Thanks.
by snibgo
2019-02-17T05:59:59-07:00
Forum: Bugs
Topic: Documentation page vanished
Replies: 2
Views: 60

Documentation page vanished

The page at http://www.imagemagick.org/script/fx.php seems to have disappeared.
by snibgo
2019-02-16T10:13:50-07:00
Forum: Users
Topic: Apply shadow to rectangle with alpha
Replies: 10
Views: 197

Re: Apply shadow to rectangle with alpha

You are directly drawing a rectangle on infile.png, and then making a shadow of the result.

Instead, you need to make an image that is the rectangle. Then make a shadow of that, then merge those two images, then composite that over infile.png.
by snibgo
2019-02-16T09:45:28-07:00
Forum: Users
Topic: Converting an HDR10 image
Replies: 6
Views: 186

Re: Converting an HDR10 image

... is there a way to do an... inverse 2084? Yes, and apparently your img_53.jpg has already had that inverse applied. Based on the Wikipedia page I cited, the forwards 2084 transformation is (Windows BAT syntax): set c1=0.8359375 set c2=18.8515625 set c3=18.6875 set m1=0.1593017578125 set m2=78.84...
by snibgo
2019-02-16T08:52:09-07:00
Forum: Users
Topic: Remove background using special markers
Replies: 6
Views: 131

Re: Remove background using special markers

This is like motion capture in the movies: targets are stuck to actors, the camera captures the actions, and computers replace the actors with animated figures. The targets can be something like these (Windows syntax): magick ^ -size 100x100 ^ xc:Black xc:White +append ^ ( +clone -flop ) ^ -append +...
by snibgo
2019-02-16T07:42:55-07:00
Forum: Users
Topic: Apply shadow to rectangle with alpha
Replies: 10
Views: 197

Re: Apply shadow to rectangle with alpha

Since the rectangle may have alpha, layering the first rectangle over a blurred rectangle would affect the overall color\transparency of the rectangle, right? Yes. You are making an image from three components. From front to back, these are: (1) a semi-transparent rectangle, (2) a semi-transparent ...
by snibgo
2019-02-15T18:38:04-07:00
Forum: Users
Topic: Adjusting 8bit to 'level' and compose properly into 16bit range
Replies: 6
Views: 143

Re: Adjusting 8bit to 'level' and compose properly into 16bit range

If you just want to count them:

Code: Select all

magick toes.png -unique-colors -format %w info:

62206
by snibgo
2019-02-15T10:20:43-07:00
Forum: Users
Topic: Adjusting 8bit to 'level' and compose properly into 16bit range
Replies: 6
Views: 143

Re: Adjusting 8bit to 'level' and compose properly into 16bit range

How about reading the grayscale (8-bit) inputs, then "-evaluate-sequence Mean", then write the (16-bit) output? That seems to do everything you want. Of course, you can "-background None -compose Plus -layers flatten" to add the images to each other, then divide by whatever you want. Or do the divis...
by snibgo
2019-02-15T10:07:50-07:00
Forum: Users
Topic: Converting an HDR10 image
Replies: 6
Views: 186

Re: Converting an HDR10 image

Okay, so if we assume img_53.jpg is sRGB and the task is to make it "look reasonable", then the image (without the black bands) is an ordinary photo so I would define "reasonable" as pixel values spanning the range 0 to 100% ("-auto-level") with a mean around 0.5 ("-auto-gamma") and a standard devia...
by snibgo
2019-02-15T08:40:48-07:00
Forum: Users
Topic: Converting an HDR10 image
Replies: 6
Views: 186

Re: Converting an HDR10 image

According to https://en.wikipedia.org/wiki/High-dynamic-range_video#HDR10 , HDR10 uses the REC2020 colorspace, and the SMPTE ST 2084 (PQ) transfer function. That page also gives the transformation from linear to SMPTE ST 2084. I notice that the pixel values of your input img_53.jpg range from 0 to 6...