I’ve written a simple C program which uses MagickWand to convert 11 successive GIF images into a single animated GIF file. This is the code. #include “MagickWand/studio.h” #include “MagickWand/MagickWand.h” # include “MagickWand/mogrify-private.h” #include “MagickCore/string-private.h”. Use MagickWand to convert, compose, and edit images from the C language. There is also the low-level MagickCore library for wizard-level developers.
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ImageMagick: Application Program Interfaces
Each example is presented as a C function, complete with headers, so that it can be copied to a file and then included in your own C project. Some of the examples show a command line “program” and how to achieve the equivalent output using MagickWand.
By “equivalent” I mean that the program produces the same image as the command line example – it won’t necessarily be exactly how it is achieved by the convert program. In some cases there is only one command line example to replicate but in others there can be 3 or 4 commands which build on each other to produce a final result.
In most of these cases I have created one C function which replicates all the commands but each section of code will show how it relates to the original commands. There is little or no error magiciwand in the examples but you should add magickdand own where needed.
convert.c File Reference
For example, the MagickReadImage function returns a true or magicwkand value depending upon whether the read succeeded and you should check this using code similar to this:. You should note that there are a lot of MagickWand functions which are declared as returning a boolean result but which will always return MagickTrue and are therefore not worth checking.
This is particularly true with the DrawingWand commands.
For example, even if DrawSetFont doesn’t find the font you specify, it will return MagickTrue because it will set the font to your default system font. If you haven’t used MagickWand before, you should start with something easy such as this: Convert the builtin logo: It is easy to see that to make this convert one of your own input files to another format you just replace “logo: The MagickReadImage function is very versatile.
It will accept a website URL which links to an image somewhere on the internet or it can generate a magicksand coloured canvas using the “xc: If you use the “xc: It is worthwhile to read the “pseudo Image” and “Built-in Images” sections near the bottom of the ImageMagick Formats page to see what other pseudo files are available.
Just in case you are deciding whether to use MagickCore instead of MagickWand, first look at the simple example I showed in the previous paragraph and then look at the equivalent written for MagickCore: I think you’ll agree that even in this simple example, the MagickWand version converf much easier to read and write.
Each image is shown on a gray background to show transparent images better.
Change the colour of one pixel in the logo: For example, the MagickReadImage function returns a true or false value depending upon whether the read succeeded and you should check this using code similar to this: