From 8bcf586b78fea574a791fcf1f3522a800a4d5c79 Mon Sep 17 00:00:00 2001 From: Richard Hughes Date: Thu, 24 Mar 2011 15:05:56 +0000 Subject: trivial: add another FAQ entry for applications --- doc/website/faq.html | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) (limited to 'doc') diff --git a/doc/website/faq.html b/doc/website/faq.html index 712cd97..5fe416a 100644 --- a/doc/website/faq.html +++ b/doc/website/faq.html @@ -22,6 +22,7 @@ +
  • How would an application like Simple Scan use colord?
  • What is a qualifier used for?
  • How do system daemons add devices and profiles?
  • How would a system daemon like CUPS use colord?
    • @@ -159,6 +160,62 @@ already being used by CUPS in the cupsICCProfile PPD Extensions format.

    +
    +

    How would an application like Simple Scan use colord?

    +

    +It's actually really easy. +Simple Scan already knows the SANE_Device object of the +scanner that it wants to use. +From the SANE_Device object we can easily get the +device_id for the color managed device in colord. +To do this, refer to the +device and profile specification for scanner devices. +This specifies the device_id for a sane device is made up from +"sane_" + sane_device->model. +

    +

    +We can now query colord using +libcolord for the device that matches this ID: +

    +
    +    CdClient *client = NULL;
+    CdDevice *device = NULL;
+    CdProfile *profile = NULL;
+    GError *error = NULL;
+
+    /* create a connection to colord */
+    client = cd_client_new ();
+
+    /* find the device for a specific ID */
+    device = cd_client_find_device_sync (client, device_id, NULL, &error);
+    if (device == NULL) {
+        g_warning ("failed to find a device in colord: %s,
+                   error->message);
+        g_error_free (error);
+        goto out;
+    }
+
+    /* get the default profile for this device */
+    profile = cd_device_get_default_profile (device);
+    if (profile == NULL)
+        goto out;
+
+    /* TODO: use lcms to convert the scanned image */
+    g_message ("need to use: %s", cd_profile_get_filename (profile));
+out:
+    if (profile != NULL)
+        g_object_unref (profile);
+    if (device != NULL)
+        g_object_unref (device);
+    g_object_unref (client);
+
    +

    +If you're not happy gaining an additional dependency of libcolord, then +it's also pretty easy to use raw DBus calls to do the same thing. +See the +examples folder for some code samples. +

    +

    How do system daemons add devices and profiles?

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