* README for the ImageMagick Emacs branch This is the imagemagick branch of Emacs. Imagemagick can now be used to load many new image formats, and also do useful transforms like scaling and rotation. This file will attempt to contain draft NEWS, Changelog and manual entries for the new functionality. You might need to regenerate the configure scripts: aclocal automake autoheader autoconf ./configure --with-imagemagick * TODO image-type-header-regexps priorities the jpeg loader over the imagemagick one. This is not wrong, but how should a user go about prefering the imagemagick loader? The user might like zooming etc in jpegs. try (setq image-type-header-regexps nil) for a quick hack to prefer imagemagick over the jpg loader. * TODO For some reason its unbearably slow to look at a page in a large image bundle using the :index feature. The imagemagick "display" command is also a bit slow, but nowhere near as slow as the emacs code. It seems imagemagick tries to unpack every page when loading the bundle. This feature is not the primary usecase for the imagemagick patch though. ImageMagick 6.6.2-9 introduced a bugfix for single page djvu load. It is now way faster to use the :index feature, but its still not very fast. ** DONE optimize number of pages calculation for bundles as suggested by imagemagick forum: "set the density to something low like 2 and use MagickPingImage()" ** TODO try to cache the num pages calculation. it can take a while to calculate the number of pages, and if you need to do it for each page view, page-flipping becomes uselessly slow. * TODO integrate with image-dired * TODO integrate with docview. * TODO integrate with image-mode Some work has been done, M-x image-transform-fit-to-height will fit the image to the height of the Emacs window for instance. * TODO look for optimizations for handling images with low depth Currently the code seems to default to 24 bit RGB which is costly for images with lower bit depth. * TODO complete documentation drafts below * DONE fix inconsistencys with spelling of imagemagick in the src * DONE report number of images in image bundle types somehow Works like for "gif" support. Thanks to Juri Linkov. * DONE probably add pdf to inhibited types * DONE inhibit types is defconst should probably be defcustom * TODO decide what to do with some uncommitted imagemagick support functions for image size etc. * TODO Test with more systems Tested on Fedora 12, Fedora 14 so far, and the libmagick that ships with it. Ubuntu 8.04 was also tested, but it seems it ships a broken ImageMagick. I also tried using an imagemagick compiled from their SVN, in parallell with the one packaged by Fedora, it worked well. * DONE Also need some way to handle render methods that only work on newer ImageMagicks Is handled by configure now * Some nits from Stefan Monnier I just took a quick look at the code and I see the following nits to fix: ** DONE obviously a merge will have to come with a good ChangeLog. ** DONE also the merge will need to come with documentation. Maybe not in the Texinfo form yet, but at least in the etc/NEWS with enough info that describes the `scale' and other such arguments that someone can start using them. ** DONE the README talks about naming inconsistencies, I think these should be fixed before a first commit (should be straightforward). ** DONE the "let" in image.el should not be followed by a line break and the while should be replaced by a dolist. ** DONE the prototype of imagemagick_load_image has some odd indentation in ([[2010.06.14]]) its args, not sure what happened. ** DONE a few lines in the C code break the 80columns limit. ** DONE please use ANSI style function declarations rather than K&R for new code. ([[2010.06.14]]) ** DONE you can get rid of the prototypes by reordering the code. ([[2010.06.14]]) ** DONE the docstrings in DEFUN should not be indented (they'll display ([[2010.06.14]]) weirdly otherwise in C-h f). ** DONE Some "{" are at the end of a for/if rather than on their own line. ([[2010.06.14]]) ** DONE why use "*( imtypes + i)" rather than "imtypes[i]"? ([[2010.06.14]]) ** DONE some "," lack a space after them. ([[2010.06.14]]) ** DONE several "=" and "==" lack spaces around them. ([[2010.06.14]]) * NEWS entry ** ImageMagick support It is now possible to use the Imagemagick library to load many new image formats in Emacs. To enable, use the following configure option: --with-imagemagick The new function (imagemagick-types) returns a list of image file extensions that your installation of imagemagick supports. The function (imagemagick-register-types) will enable the imagemagick support for the extensions in imagemagick-types minus the types listed in imagemagick-types-inhibit. imagemagick-types-inhibit has the value '(C HTML HTM TXT PDF) by default. This means imagemagick will be used also to load jpeg files, if you have both jpeg and imagemagick libraries linked. Add 'JPG to imagemagick-types-inhibit if you do not want this. imagemagick-render-type is a new variable which can be set to choose between screen render methods. - 0 is a conservative metod which works with older ImageMagick versions. It is a bit slow, but robust. - 1 utilizes a newer ImageMagick method Images loaded with imagemagick will support a couple of new display specification behaviours: - if the :width and :height keywords are specified, these values are used for scaling the image. If only one of :width or :height is specified, the other one will be calculated so as to preserve the aspect ratio.If both :width and :height are specified, aspect ratio will not be preserved. - :rotation specifies a rotation angle in degrees. - :index specifies which image inside an image bundle file format, such as TIFF or DJVM, to view. The image-metadata function can be used to retrieve the total number of images in an image bundle. This is simmilar to how GIF files work. * Manual entry nothing yet, but the NEWS entry could be adapted.