# cairo_jpg ## Introduction This is an implementation of functions to import and export Cairo surfaces from and to JPEG files. It uses the same function prototypes as Cairo's [PNG support](http://www.cairographics.org/manual/cairo-PNG-Support.html). ## Description The implementation is done on top of the Cairo API. It does not access Cairo-internal functions. For compression and decompression [libjpeg](http://libjpeg.sourceforge.net/) is used. The following prototypes are implemented. Their functionallity is equal to the PNG functions of Cairo with the advance that there are memory-buffer-based functions as well. ```C cairo_status_t cairo_image_surface_write_to_jpeg_mem(cairo_surface_t *sfc, unsigned char **data, size_t *len, int quality); cairo_status_t cairo_image_surface_write_to_jpeg_stream(cairo_surface_t *sfc, cairo_write_func_t write_func, void *closure, int quality); cairo_status_t cairo_image_surface_write_to_jpeg(cairo_surface_t *sfc, const char *filename, int quality); cairo_surface_t *cairo_image_surface_create_from_jpeg_mem(void *data, size_t len); cairo_surface_t *cairo_image_surface_create_from_jpeg_stream(cairo_read_func_t read_func, void *closure); cairo_surface_t *cairo_image_surface_create_from_jpeg(const char *filename); ``` To compile this code you need to have installed the packages libcairo2-dev and libjpeg-dev. Compile with the following command to create an object file linkable to your code: ```Shell gcc -Wall -c `pkg-config cairo libjpeg --cflags --libs` cairo_jpg.c ``` Please have a look at the comments within the source files for further details. Don't hesitate to contact me at [bf@abenteuerland.at](mailto:bf@abenteuerland.at).