Oyranos User API Documentation

Descriptive Contents

Introduction | Installation | References
User Tools Documentation | Environment Variables | User API Documentation | Programming Tutorial | Threading | Extending Oyranos

License

new BSD http://www.opensource.org/licenses/BSD-3-Clause

Author

Kai-Uwe Behrmann and others

Since

March 2004

Internet

http://www.oyranos.org/about

Development

https://github.com/oyranos-cms/oyranos

Introduction

Oyranos is intended as a entry point for color savy applications. In its current stage it configures profile paths, sets default profiles, maps devices to profiles, sets a monitor profile in X and uploads a vcgt tag. This means for instance all applications using Oyranos will use for a incoming digital camera picture the same profile and watch it through the same monitor profile with the same options for rendering intent, simulation and so on.

User Tools Documentation

• oyranos-icc - access embedded profiles from images, color convert images
• oyranos-monitor - a commandline tool for calling from a setup script like .xinitrc. It selects a profile for the current monitor and sets up the X server at startup time. Usage:

  # select a monitor profile, load the binary blob into X and fill the
  # VideoCardGammaTable, if appropriate
  oyranos-monitor
  

• oyranos-policy - a tool to set a policy from a xml file. Use it like:

  oyranos-policy `oyranos-config --syscolordir`/`oyranos-config --settingsdirname`/office.policy.xml
  

  Affected are default profiles and some behaviour settings.
• oyranos-profile - access profile information
• oyranos-profile-graph - draw a 2D graph from profiles
• oyranos-profiles - lookup profiles in the systems color paths, download and install
• oyranos-config-fltk - a configuration UI application, using some functions of the Oyranos APIs. If you have ICC Examin installed it can be called to show details of profiles.
• oyranos-config - a command line tool to get compiler flags to using Oyranos in your own project. Try oyranos-config –help to see the appropriate options.

User API Documentation

The basic Oyranos API gets included with oyranos.h. An application, which wants to use these functions, needs to link against Oyranos.

• Defaults Handling - obtain and manipulate user preferences and UI translations
• ICC Profile APIs - select, read, manipulate and write ICC profiles
• Device Handling - select, read, manipulate and write color device configurations
• Conversion - build and process image graphs

The monitor related interfaces are accessed through Device Handling interfaces. Loading of the according module for the device depedent libraries is done on runtime.

The key names, which Oyranos uses to store its configuration in an Elektra file tree, are defined in oyranos_definitions.h.
More in depth topics about programming with Oyranos can be found on the coding page.

Programming Tutorial

Frist you have to put a

#include <oyranos.h> 

in your source text, in order to use Oyranos.

int main( int argc, char ** argv ) {
  int oyranos_version = oyVersion( 0 );
  return 0;
}

oyranos-config –cflags delivers the compiler flags and oyranos-config –ldflags the linker flags.

Then you can put Oyranos functions in your code and compile with:

cc `oyranos-config --cflags --ldflags` mycode.c -o myApp 

to link Oyranos into your application.

The second code sample will be more useful and handle obtaining a monitor profile:

#include <oyranos.h>
#include <oyranos_devices.h>
#include <oyConversion_s.h>
#include <stdio.h>

int main( int argc, char ** argv ) {
  oyConfigs_s * devices = NULL;
  oyConfig_s * monitor = NULL;
  oyOptions_s * options = NULL;
  oyProfile_s * monitor_icc = NULL;
  const char * monitor_icc_dscr = NULL;
  // get all monitors
  oyDevicesGet( NULL, "monitor", NULL, &devices );
  // just pick the first monitor
  monitor = oyConfigs_Get( devices, 0 );
  /* get XCM_ICC_COLOR_SERVER_TARGET_PROFILE_IN_X_BASE */
  oyOptions_SetFromText( &options,
              "//"OY_TYPE_STD"/config/icc_profile.x_color_region_target", "yes", OY_CREATE_NEW );
  oyDeviceGetProfile( monitor, options, &monitor_icc );
  // get the profiles internal name
  monitor_icc_dscr = oyProfile_GetText( monitor_icc, oyNAME_DESCRIPTION );
  printf( "first monitor has profile: %s\n", monitor_icc_dscr );

  // now convert some colors from sRGB to monitor space
  // find the appropriate profile flags
  uint32_t icc_profile_flags =oyICCProfileSelectionFlagsFromOptions( OY_CMM_STD,
                                   "//" OY_TYPE_STD "/icc_color", NULL, 0 );
  oyProfile_s * srgb = oyProfile_FromStd( oyASSUMED_WEB, icc_profile_flags, 0 );
  float rgb_in[9] = {0,0,0, 0.5,0.5,0.5, 1,1,1};
  float rgb_moni[9];
  // setup the color context
  oyConversion_s * cc = oyConversion_CreateBasicPixelsFromBuffers(
                         srgb, rgb_in, OY_TYPE_123_FLOAT,
                         monitor_icc, rgb_moni, OY_TYPE_123_FLOAT,
                         NULL, 3 );
  // convert by running the conversion graph
  oyConversion_RunPixels( cc, NULL );
  // show the source colors and the converted colors
  int i;
  for(i = 0; i < 3; ++i)
    printf("%.02f %.02f %.02f -> %.05f %.05f %.05f\n",
           rgb_in[3*i+0],rgb_in[3*i+1],rgb_in[3*i+2], rgb_moni[3*i+0],rgb_moni[3*i+1],rgb_moni[3*i+2]);

  return 0;
}

The code is from tutorial1.c

Writing of filters and modules for Oyranos is covered in the Extending Oyranos page.