compositor/main.c

@@ -126,6 +126,7 @@ struct wet_compositor {
 	struct wl_list child_process_list;
 	pid_t autolaunch_pid;
 	bool autolaunch_watch;
+	bool use_color_manager;
 };
 
 static FILE *weston_logfile = NULL;
@@ -1095,6 +1096,7 @@ static int
 weston_compositor_init_config(struct weston_compositor *ec,
 			      struct weston_config *config)
 {
+	struct wet_compositor *compositor = to_wet_compositor(ec);
 	struct xkb_rule_names xkb_names;
 	struct weston_config_section *s;
 	int repaint_msec;
@@ -1143,6 +1145,8 @@ weston_compositor_init_config(struct weston_compositor *ec,
 	if (color_management) {
 		if (weston_compositor_load_color_manager(ec) < 0)
 			return -1;
+		else
+			compositor->use_color_manager = true;
 	}
 
 	/* weston.ini [libinput] */
@@ -1302,6 +1306,48 @@ wet_output_set_transform(struct weston_output *output,
 	return 0;
 }
 
+static int
+wet_output_set_color_profile(struct weston_output *output,
+			     struct weston_config_section *section,
+			     struct weston_color_profile *parent_winsys_profile)
+{
+	struct wet_compositor *compositor = to_wet_compositor(output->compositor);
+	struct weston_color_profile *cprof;
+	char *icc_file = NULL;
+	bool ok;
+
+	if (!compositor->use_color_manager)
+		return 0;
+
+	if (section) {
+		weston_config_section_get_string(section, "icc_profile",
+						 &icc_file, NULL);
+	}
+
+	if (icc_file) {
+		cprof = weston_compositor_load_icc_file(output->compositor,
+							icc_file);
+		free(icc_file);
+	} else if (parent_winsys_profile) {
+		cprof = weston_color_profile_ref(parent_winsys_profile);
+	} else {
+		return 0;
+	}
+
+	if (!cprof)
+		return -1;
+
+	ok = weston_output_set_color_profile(output, cprof);
+	if (!ok) {
+		weston_log("Error: failed to set color profile '%s' for output %s\n",
+			   weston_color_profile_get_description(cprof),
+			   output->name);
+	}
+
+	weston_color_profile_unref(cprof);
+	return ok ? 0 : -1;
+}
+
 static void
 allow_content_protection(struct weston_output *output,
 			struct weston_config_section *section)
@@ -1366,6 +1412,9 @@ wet_configure_windowed_output_from_config(struct weston_output *output,
 		return -1;
 	}
 
+	if (wet_output_set_color_profile(output, section, NULL) < 0)
+		return -1;
+
 	if (api->output_set_size(output, width, height) < 0) {
 		weston_log("Cannot configure output \"%s\" using weston_windowed_output_api.\n",
 			   output->name);
@@ -1806,6 +1855,9 @@ drm_backend_output_configure(struct weston_output *output,
 		return -1;
 	}
 
+	if (wet_output_set_color_profile(output, section, NULL) < 0)
+		return -1;
+
 	weston_config_section_get_string(section,
 					 "gbm-format", &gbm_format, NULL);
 
@@ -2305,6 +2357,9 @@ drm_backend_remoted_output_configure(struct weston_output *output,
 		return -1;
 	};
 
+	if (wet_output_set_color_profile(output, section, NULL) < 0)
+		return -1;
+
 	weston_config_section_get_string(section, "gbm-format", &gbm_format,
 					 NULL);
 	api->set_gbm_format(output, gbm_format);
@@ -2456,6 +2511,9 @@ drm_backend_pipewire_output_configure(struct weston_output *output,
 		return -1;
 	}
 
+	if (wet_output_set_color_profile(output, section, NULL) < 0)
+		return -1;
+
 	weston_config_section_get_string(section, "seat", &seat, "");
 
 	api->set_seat(output, seat);

include/libweston/libweston.h

@@ -79,6 +79,7 @@ struct linux_dmabuf_buffer;
 struct weston_recorder;
 struct weston_pointer_constraint;
 struct ro_anonymous_file;
+struct weston_color_profile;
 struct weston_color_transform;
 
 enum weston_keyboard_modifier {
@@ -373,6 +374,7 @@ struct weston_output {
 	bool enabled; /**< is in the output_list, not pending list */
 	int scale;
 
+	struct weston_color_profile *color_profile;
 	struct weston_color_transform *from_sRGB_to_output;
 	struct weston_color_transform *from_sRGB_to_blend;
 	struct weston_color_transform *from_blend_to_output;
@@ -2082,6 +2084,10 @@ void
 weston_output_set_transform(struct weston_output *output,
 			    uint32_t transform);
 
+bool
+weston_output_set_color_profile(struct weston_output *output,
+				struct weston_color_profile *cprof);
+
 void
 weston_output_init(struct weston_output *output,
 		   struct weston_compositor *compositor,
@@ -2126,6 +2132,19 @@ void
 weston_timeline_refresh_subscription_objects(struct weston_compositor *wc,
 					     void *object);
 
+struct weston_color_profile *
+weston_color_profile_ref(struct weston_color_profile *cprof);
+
+void
+weston_color_profile_unref(struct weston_color_profile *cprof);
+
+const char *
+weston_color_profile_get_description(struct weston_color_profile *cprof);
+
+struct weston_color_profile *
+weston_compositor_load_icc_file(struct weston_compositor *compositor,
+				const char *path);
+
 #ifdef  __cplusplus
 }
 #endif

libweston/color-lcms/color-lcms.c

@@ -57,6 +57,10 @@ cmlcms_get_surface_color_transform(struct weston_color_manager *cm_base,
 	};
 	struct cmlcms_color_transform *xform;
 
+	/* TODO: use output color profile */
+	if (output->color_profile)
+		return false;
+
 	xform = cmlcms_color_transform_get(cm, &param);
 	if (!xform)
 		return false;
@@ -82,6 +86,10 @@ cmlcms_get_output_color_transform(struct weston_color_manager *cm_base,
 	};
 	struct cmlcms_color_transform *xform;
 
+	/* TODO: use output color profile */
+	if (output->color_profile)
+		return false;
+
 	xform = cmlcms_color_transform_get(cm, &param);
 	if (!xform)
 		return false;
@@ -96,6 +104,11 @@ cmlcms_get_sRGB_to_output_color_transform(struct weston_color_manager *cm_base,
 					  struct weston_color_transform **xform_out)
 {
 	/* Assumes output color space is sRGB SDR */
+
+	/* TODO: use output color profile */
+	if (output->color_profile)
+		return false;
+
 	/* Identity transform */
 	*xform_out = NULL;
 
@@ -114,6 +127,10 @@ cmlcms_get_sRGB_to_blend_color_transform(struct weston_color_manager *cm_base,
 	};
 	struct cmlcms_color_transform *xform;
 
+	/* TODO: use output color profile */
+	if (output->color_profile)
+		return false;
+
 	xform = cmlcms_color_transform_get(cm, &param);
 	if (!xform)
 		return false;
@@ -159,6 +176,7 @@ cmlcms_destroy(struct weston_color_manager *cm_base)
 	struct weston_color_manager_lcms *cm = get_cmlcms(cm_base);
 
 	assert(wl_list_empty(&cm->color_transform_list));
+	assert(wl_list_empty(&cm->color_profile_list));
 
 	cmsDeleteContext(cm->lcms_ctx);
 	free(cm);
@@ -178,6 +196,8 @@ weston_color_manager_create(struct weston_compositor *compositor)
 	cm->base.supports_client_protocol = true;
 	cm->base.init = cmlcms_init;
 	cm->base.destroy = cmlcms_destroy;
+	cm->base.destroy_color_profile = cmlcms_destroy_color_profile;
+	cm->base.get_color_profile_from_icc = cmlcms_get_color_profile_from_icc;
 	cm->base.destroy_color_transform = cmlcms_destroy_color_transform;
 	cm->base.get_surface_color_transform =
 	      cmlcms_get_surface_color_transform;
@@ -188,6 +208,7 @@ weston_color_manager_create(struct weston_compositor *compositor)
 	      cmlcms_get_sRGB_to_blend_color_transform;
 
 	wl_list_init(&cm->color_transform_list);
+	wl_list_init(&cm->color_profile_list);
 
 	return &cm->base;
 }

libweston/color-lcms/color-lcms.h

@@ -38,6 +38,7 @@ struct weston_color_manager_lcms {
 	cmsContext lcms_ctx;
 
 	struct wl_list color_transform_list; /* cmlcms_color_transform::link */
+	struct wl_list color_profile_list; /* cmlcms_color_profile::link */
 };
 
 static inline struct weston_color_manager_lcms *
@@ -46,6 +47,37 @@ get_cmlcms(struct weston_color_manager *cm_base)
 	return container_of(cm_base, struct weston_color_manager_lcms, base);
 }
 
+struct cmlcms_md5_sum {
+	uint8_t bytes[16];
+};
+
+struct cmlcms_color_profile {
+	struct weston_color_profile base;
+
+	/* struct weston_color_manager_lcms::color_profile_list */
+	struct wl_list link;
+
+	cmsHPROFILE profile;
+	struct cmlcms_md5_sum md5sum;
+};
+
+static inline struct cmlcms_color_profile *
+get_cprof(struct weston_color_profile *cprof_base)
+{
+	return container_of(cprof_base, struct cmlcms_color_profile, base);
+}
+
+bool
+cmlcms_get_color_profile_from_icc(struct weston_color_manager *cm,
+				  const void *icc_data,
+				  size_t icc_len,
+				  const char *name_part,
+				  struct weston_color_profile **cprof_out,
+				  char **errmsg);
+
+void
+cmlcms_destroy_color_profile(struct weston_color_profile *cprof_base);
+
 /*
  * Perhaps a placeholder, until we get actual color spaces involved and
  * see how this would work better.

libweston/color-lcms/color-profile.c

+/*
+ * Copyright 2019 Sebastian Wick
+ * Copyright 2021 Collabora, Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "config.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <libweston/libweston.h>
+
+#include "color.h"
+#include "color-lcms.h"
+#include "shared/helpers.h"
+#include "shared/string-helpers.h"
+
+/* FIXME: sync with spec! */
+static bool
+validate_icc_profile(cmsHPROFILE profile, char **errmsg)
+{
+	cmsColorSpaceSignature cs = cmsGetColorSpace(profile);
+	uint32_t nr_channels = cmsChannelsOf(cs);
+	uint8_t version = cmsGetEncodedICCversion(profile) >> 24;
+
+	if (version != 2 && version != 4) {
+		str_printf(errmsg,
+			   "ICC profile major version %d is unsupported, should be 2 or 4.",
+			   version);
+		return false;
+	}
+
+	if (nr_channels != 3) {
+		str_printf(errmsg,
+			   "ICC profile must contain 3 channels for the color space, not %u.",
+			   nr_channels);
+		return false;
+	}
+
+	if (cmsGetDeviceClass(profile) != cmsSigDisplayClass) {
+		str_printf(errmsg, "ICC profile is required to be of Display device class, but it is not.");
+		return false;
+	}
+
+	return true;
+}
+
+static struct cmlcms_color_profile *
+cmlcms_find_color_profile_by_md5(const struct weston_color_manager_lcms *cm,
+				 const struct cmlcms_md5_sum *md5sum)
+{
+	struct cmlcms_color_profile *cprof;
+
+	wl_list_for_each(cprof, &cm->color_profile_list, link) {
+		if (memcmp(cprof->md5sum.bytes,
+			   md5sum->bytes, sizeof(md5sum->bytes)) == 0)
+			return cprof;
+	}
+
+	return NULL;
+}
+
+static struct cmlcms_color_profile *
+cmlcms_color_profile_create(struct weston_color_manager_lcms *cm,
+			    cmsHPROFILE profile,
+			    char *desc,
+			    char **errmsg)
+{
+	struct cmlcms_color_profile *cprof;
+
+	cprof = zalloc(sizeof *cprof);
+	if (!cprof)
+		return NULL;
+
+	weston_color_profile_init(&cprof->base, &cm->base);
+	cprof->base.description = desc;
+	cprof->profile = profile;
+	cmsGetHeaderProfileID(profile, cprof->md5sum.bytes);
+	wl_list_insert(&cm->color_profile_list, &cprof->link);
+
+	return cprof;
+}
+
+static void
+cmlcms_color_profile_destroy(struct cmlcms_color_profile *cprof)
+{
+	wl_list_remove(&cprof->link);
+	cmsCloseProfile(cprof->profile);
+	free(cprof->base.description);
+	free(cprof);
+}
+
+static char *
+make_icc_file_description(cmsHPROFILE profile,
+			  const struct cmlcms_md5_sum *md5sum,
+			  const char *name_part)
+{
+	char md5sum_str[sizeof(md5sum->bytes) * 2 + 1];
+	char *desc;
+	size_t i;
+
+	for (i = 0; i < sizeof(md5sum->bytes); i++) {
+		snprintf(md5sum_str + 2 * i, sizeof(md5sum_str) - 2 * i,
+			 "%02x", md5sum->bytes[i]);
+	}
+
+	str_printf(&desc, "ICCv%f %s %s", cmsGetProfileVersion(profile),
+		   name_part, md5sum_str);
+
+	return desc;
+}
+
+bool
+cmlcms_get_color_profile_from_icc(struct weston_color_manager *cm_base,
+				  const void *icc_data,
+				  size_t icc_len,
+				  const char *name_part,
+				  struct weston_color_profile **cprof_out,
+				  char **errmsg)
+{
+	struct weston_color_manager_lcms *cm = get_cmlcms(cm_base);
+	cmsHPROFILE profile;
+	struct cmlcms_md5_sum md5sum;
+	struct cmlcms_color_profile *cprof;
+	char *desc = NULL;
+
+	if (!icc_data || icc_len < 1) {
+		str_printf(errmsg, "No ICC data.");
+		return false;
+	}
+	if (icc_len >= UINT32_MAX) {
+		str_printf(errmsg, "Too much ICC data.");
+		return false;
+	}
+
+	profile = cmsOpenProfileFromMemTHR(cm->lcms_ctx, icc_data, icc_len);
+	if (!profile) {
+		str_printf(errmsg, "ICC data not understood.");
+		return false;
+	}
+
+	if (!validate_icc_profile(profile, errmsg))
+		goto err_close;
+
+	if (!cmsMD5computeID(profile)) {
+		str_printf(errmsg, "Failed to compute MD5 for ICC profile.");
+		goto err_close;
+	}
+
+	cmsGetHeaderProfileID(profile, md5sum.bytes);
+	cprof = cmlcms_find_color_profile_by_md5(cm, &md5sum);
+	if (cprof) {
+		*cprof_out = weston_color_profile_ref(&cprof->base);
+		cmsCloseProfile(profile);
+		return true;
+	}
+
+	desc = make_icc_file_description(profile, &md5sum, name_part);
+	if (!desc)
+		goto err_close;
+
+	cprof = cmlcms_color_profile_create(cm, profile, desc, errmsg);
+	if (!cprof)
+		goto err_close;
+
+	*cprof_out = &cprof->base;
+	return true;
+
+err_close:
+	free(desc);
+	cmsCloseProfile(profile);
+	return false;
+}
+
+void
+cmlcms_destroy_color_profile(struct weston_color_profile *cprof_base)
+{
+	struct cmlcms_color_profile *cprof = get_cprof(cprof_base);
+
+	cmlcms_color_profile_destroy(cprof);
+}

libweston/color-lcms/meson.build

@@ -9,6 +9,7 @@ endif
 
 srcs_color_lcms = [
 	'color-lcms.c',
+	'color-profile.c',
 	'color-transform.c',
 ]
 

libweston/color-noop.c

@@ -29,6 +29,7 @@
 
 #include "color.h"
 #include "shared/helpers.h"
+#include "shared/string-helpers.h"
 
 struct weston_color_manager_noop {
 	struct weston_color_manager base;
@@ -40,6 +41,24 @@ get_cmnoop(struct weston_color_manager *cm_base)
 	return container_of(cm_base, struct weston_color_manager_noop, base);
 }
 
+static void
+cmnoop_destroy_color_profile(struct weston_color_profile *cprof)
+{
+	/* Never called, as never creates an actual color profile. */
+}
+
+static bool
+cmnoop_get_color_profile_from_icc(struct weston_color_manager *cm,
+				  const void *icc_data,
+				  size_t icc_len,
+				  const char *name_part,
+				  struct weston_color_profile **cprof_out,
+				  char **errmsg)
+{
+	str_printf(errmsg, "ICC profiles are unsupported.");
+	return false;
+}
+
 static void
 cmnoop_destroy_color_transform(struct weston_color_transform *xform)
 {
@@ -53,7 +72,7 @@ cmnoop_get_surface_color_transform(struct weston_color_manager *cm_base,
 				   struct weston_surface_color_transform *surf_xform)
 {
 	/* TODO: Assert surface has no colorspace set */
-	/* TODO: Assert output has no colorspace set */
+	assert(output->color_profile == NULL);
 
 	/* Identity transform */
 	surf_xform->transform = NULL;
@@ -67,7 +86,7 @@ cmnoop_get_output_color_transform(struct weston_color_manager *cm_base,
 				  struct weston_output *output,
 				  struct weston_color_transform **xform_out)
 {
-	/* TODO: Assert output has no colorspace set */
+	assert(output->color_profile == NULL);
 
 	/* Identity transform */
 	*xform_out = NULL;
@@ -80,7 +99,7 @@ cmnoop_get_sRGB_to_output_color_transform(struct weston_color_manager *cm_base,
 					  struct weston_output *output,
 					  struct weston_color_transform **xform_out)
 {
-	/* TODO: Assert output has no colorspace set */
+	assert(output->color_profile == NULL);
 
 	/* Identity transform */
 	*xform_out = NULL;
@@ -93,7 +112,7 @@ cmnoop_get_sRGB_to_blend_color_transform(struct weston_color_manager *cm_base,
 					 struct weston_output *output,
 					 struct weston_color_transform **xform_out)
 {
-	/* TODO: Assert output has no colorspace set */
+	assert(output->color_profile == NULL);
 
 	/* Identity transform */
 	*xform_out = NULL;
@@ -131,6 +150,8 @@ weston_color_manager_noop_create(struct weston_compositor *compositor)
 	cm->base.supports_client_protocol = false;
 	cm->base.init = cmnoop_init;
 	cm->base.destroy = cmnoop_destroy;
+	cm->base.destroy_color_profile = cmnoop_destroy_color_profile;
+	cm->base.get_color_profile_from_icc = cmnoop_get_color_profile_from_icc;
 	cm->base.destroy_color_transform = cmnoop_destroy_color_transform;
 	cm->base.get_surface_color_transform =
 	      cmnoop_get_surface_color_transform;

libweston/color.c

 /*
+ * Copyright 2019 Sebastian Wick
  * Copyright 2021 Collabora, Ltd.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -27,10 +28,88 @@
 
 #include <libweston/libweston.h>
 #include <assert.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <string.h>
 
 #include "color.h"
 #include "libweston-internal.h"
 
+/**
+ * Increase reference count of the color profile object
+ *
+ * \param cprof The color profile. NULL is accepted too.
+ * \return cprof.
+ */
+WL_EXPORT struct weston_color_profile *
+weston_color_profile_ref(struct weston_color_profile *cprof)
+{
+	/* NULL is a valid color space: sRGB */
+	if (!cprof)
+		return NULL;
+
+	assert(cprof->ref_count > 0);
+	cprof->ref_count++;
+	return cprof;
+}
+
+/**
+ * Decrease reference count and potentially destroy the color profile object
+ *
+ * \param cprof The color profile. NULL is accepted too.
+ */
+WL_EXPORT void
+weston_color_profile_unref(struct weston_color_profile *cprof)
+{
+	if (!cprof)
+		return;
+
+	assert(cprof->ref_count > 0);
+	if (--cprof->ref_count > 0)
+		return;
+
+	cprof->cm->destroy_color_profile(cprof);
+}
+
+/**
+ * Get color profile description
+ *
+ * A description of the profile is meant for human readable logs.
+ *
+ * \param cprof The color profile, NULL is accepted too.
+ * \returns The color profile description, valid as long as the
+ * color profile itself is.
+ */
+WL_EXPORT const char *
+weston_color_profile_get_description(struct weston_color_profile *cprof)
+{
+	if (cprof)
+		return cprof->description;
+	else
+		return "built-in default sRGB SDR profile";
+}
+
+/**
+ * Initializes a newly allocated color profile object
+ *
+ * This is used only by color managers. They sub-class weston_color_profile.
+ *
+ * The reference count starts at 1.
+ *
+ * To destroy a weston_color_profile, use weston_color_profile_unref().
+ */
+WL_EXPORT void
+weston_color_profile_init(struct weston_color_profile *cprof,
+			  struct weston_color_manager *cm)
+{
+	cprof->cm = cm;
+	cprof->ref_count = 1;
+}
+
 /**
  * Increase reference count of the color transform object
  *
@@ -100,6 +179,8 @@ void
 weston_surface_color_transform_fini(struct weston_surface_color_transform *surf_xform)
 {
 	weston_color_transform_unref(surf_xform->transform);
+	surf_xform->transform = NULL;
+	surf_xform->identity_pipeline = false;
 }
 
 /**
@@ -149,3 +230,70 @@ weston_paint_node_ensure_color_transform(struct weston_paint_node *pnode)
 		weston_log("Failed to create color transformation for a surface.\n");
 	}
 }
+
+/**
+ * Load ICC profile file
+ *
+ * Loads an ICC profile file, ensures it is fit for use, and returns a
+ * new reference to the weston_color_profile. Use weston_color_profile_unref()
+ * to free it.
+ *
+ * \param compositor The compositor instance, identifies the color manager.
+ * \param path Path to the ICC file to be open()'d.
+ * \return A color profile reference, or NULL on failure.
+ *
+ * Error messages are printed to libweston log.
+ *
+ * This function is not meant for loading profiles on behalf of Wayland
+ * clients.
+ */
+WL_EXPORT struct weston_color_profile *
+weston_compositor_load_icc_file(struct weston_compositor *compositor,
+				const char *path)
+{
+	struct weston_color_manager *cm = compositor->color_manager;
+	struct weston_color_profile *cprof = NULL;
+	int fd;
+	struct stat icc_stat;
+	void *icc_data;
+	size_t len;
+	char *errmsg = NULL;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		weston_log("Error: Cannot open ICC profile \"%s\" for reading: %s\n",
+			   path, strerror(errno));
+		return NULL;
+	}
+
+	if (fstat(fd, &icc_stat) != 0) {
+		weston_log("Error: Cannot fstat ICC profile \"%s\": %s\n",
+			   path, strerror(errno));
+		goto out_close;
+	}
+	len = icc_stat.st_size;
+	if (len < 1) {
+		weston_log("Error: ICC profile \"%s\" has no size.\n", path);
+		goto out_close;
+	}
+
+	icc_data = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (icc_data == MAP_FAILED) {
+		weston_log("Error: Cannot mmap ICC profile \"%s\": %s\n",
+			   path, strerror(errno));
+		goto out_close;
+	}
+
+	if (!cm->get_color_profile_from_icc(cm, icc_data, len,
+					    path, &cprof, &errmsg)) {
+		weston_log("Error: loading ICC profile \"%s\" failed: %s\n",
+			   path, errmsg);
+		free(errmsg);
+	}
+
+	munmap(icc_data, len);
+
+out_close:
+	close(fd);
+	return cprof;
+}

libweston/color.h

@@ -27,8 +27,20 @@
 #define WESTON_COLOR_H
 
 #include <stdbool.h>
+#include <stdint.h>
 #include <libweston/libweston.h>
 
+/**
+ * Represents a color profile description (an ICC color profile)
+ *
+ * Sub-classed by the color manager that created this.
+ */
+struct weston_color_profile {
+	struct weston_color_manager *cm;
+	int ref_count;
+	char *description;
+};
+
 /** Type or formula for a curve */
 enum weston_color_curve_type {
 	/** Identity function, no-op */
@@ -161,6 +173,35 @@ struct weston_color_manager {
 	void
 	(*destroy)(struct weston_color_manager *cm);
 
+	/** Destroy a color profile after refcount fell to zero */
+	void
+	(*destroy_color_profile)(struct weston_color_profile *cprof);
+
+	/** Create a color profile from ICC data
+	 *
+	 * \param cm The color manager.
+	 * \param icc_data Pointer to the ICC binary data.
+	 * \param icc_len Length of the ICC data in bytes.
+	 * \param name_part A string to be used in describing the profile.
+	 * \param cprof_out On success, the created object is returned here.
+	 * On failure, untouched.
+	 * \param errmsg On success, untouched. On failure, a pointer to a
+	 * string describing the error is stored here. The string must be
+	 * free()'d.
+	 * \return True on success, false on failure.
+	 *
+	 * This may return a new reference to an existing color profile if
+	 * that profile is identical to the one that would be created, apart
+	 * from name_part.
+	 */
+	bool
+	(*get_color_profile_from_icc)(struct weston_color_manager *cm,
+				      const void *icc_data,
+				      size_t icc_len,
+				      const char *name_part,
+				      struct weston_color_profile **cprof_out,
+				      char **errmsg);
+
 	/** Destroy a color transform after refcount fell to zero */
 	void
 	(*destroy_color_transform)(struct weston_color_transform *xform);
@@ -231,6 +272,10 @@ struct weston_color_manager {
 					     struct weston_color_transform **xform_out);
 };
 
+void
+weston_color_profile_init(struct weston_color_profile *cprof,
+			  struct weston_color_manager *cm);
+
 struct weston_color_transform *
 weston_color_transform_ref(struct weston_color_transform *xform);
 

libweston/compositor.c

@@ -6273,6 +6273,42 @@ weston_output_reset_color_transforms(struct weston_output *output)
 	output->from_blend_to_output = NULL;
 }
 
+static bool
+weston_output_set_color_transforms(struct weston_output *output)
+{
+	struct weston_color_manager *cm = output->compositor->color_manager;
+	struct weston_color_transform *blend_to_output = NULL;
+	struct weston_color_transform *sRGB_to_output = NULL;
+	struct weston_color_transform *sRGB_to_blend = NULL;
+	bool ok;
+
+	ok = cm->get_output_color_transform(cm, output, &blend_to_output);
+	ok = ok && cm->get_sRGB_to_output_color_transform(cm, output,
+							  &sRGB_to_output);
+	ok = ok && cm->get_sRGB_to_blend_color_transform(cm, output,
+							 &sRGB_to_blend);
+	if (!ok) {
+		weston_log("Creating color transformation for output \"%s\" failed.\n",
+			   output->name);
+		weston_color_transform_unref(blend_to_output);
+		weston_color_transform_unref(sRGB_to_output);
+		weston_color_transform_unref(sRGB_to_blend);
+
+		return false;
+	}
+
+	weston_output_reset_color_transforms(output);
+	output->from_blend_to_output = blend_to_output;
+	output->from_blend_to_output_by_backend = false;
+	output->from_sRGB_to_output = sRGB_to_output;
+	output->from_sRGB_to_blend = sRGB_to_blend;
+
+	weston_log("Output '%s' using color profile: %s\n", output->name,
+		   weston_color_profile_get_description(output->color_profile));
+
+	return true;
+}
+
 /** Removes output from compositor's list of enabled outputs
  *
  * \param output The weston_output object that is being removed.
@@ -6457,6 +6493,52 @@ weston_output_set_transform(struct weston_output *output,
 	}
 }
 
+/** Set output's color profile
+ *
+ * \param output The output to change.
+ * \param cprof The color profile to set. Can be NULL for default sRGB profile.
+ * \return True on success, or false on failure.
+ *
+ * Calling this function changes the color profile of the output. This causes
+ * all existing weston_color_transform objects related to this output via
+ * paint nodes to be unreferenced and later re-created on demand.
+ *
+ * This function may not be called from within weston_output_repaint().
+ *
+ * On failure, nothing is changed.
+ *
+ * \ingroup output
+ */
+WL_EXPORT bool
+weston_output_set_color_profile(struct weston_output *output,
+				struct weston_color_profile *cprof)
+{
+	struct weston_color_profile *old;
+	struct weston_paint_node *pnode;
+
+	old = output->color_profile;
+	output->color_profile = weston_color_profile_ref(cprof);
+
+	if (output->enabled) {
+		if (!weston_output_set_color_transforms(output)) {
+			/* Failed, roll back */
+			weston_color_profile_unref(output->color_profile);
+			output->color_profile = old;
+			return false;
+		}
+
+		/* Remove outdated cached color transformations */
+		wl_list_for_each(pnode, &output->paint_node_list, output_link) {
+			weston_surface_color_transform_fini(&pnode->surf_xform);
+			pnode->surf_xform_valid = false;
+		}
+	}
+
+	weston_color_profile_unref(old);
+
+	return true;
+}
+
 /** Initializes a weston_output object with enough data so
  ** an output can be configured.
  *
@@ -6588,12 +6670,10 @@ WL_EXPORT int
 weston_output_enable(struct weston_output *output)
 {
 	struct weston_compositor *c = output->compositor;
-	struct weston_color_manager *cm = c->color_manager;
 	struct weston_output *iterator;
 	struct weston_head *head;
 	char *head_names;
 	int x = 0, y = 0;
-	bool ok;
 
 	if (output->enabled) {
 		weston_log("Error: attempt to enable an enabled output '%s'\n",
@@ -6649,19 +6729,8 @@ weston_output_enable(struct weston_output *output)
 	wl_list_init(&output->paint_node_list);
 	wl_list_init(&output->paint_node_z_order_list);
 
-	ok = cm->get_output_color_transform(cm, output,
-					    &output->from_blend_to_output);
-	ok = ok && cm->get_sRGB_to_output_color_transform(cm, output,
-							  &output->from_sRGB_to_output);
-	ok = ok && cm->get_sRGB_to_blend_color_transform(cm, output,
-							 &output->from_sRGB_to_blend);
-	if (!ok) {
-		weston_log("Creating color transformation for output \"%s\" failed.\n",
-			   output->name);
-		weston_output_reset_color_transforms(output);
+	if (!weston_output_set_color_transforms(output))
 		return -1;
-	}
-	output->from_blend_to_output_by_backend = false;
 
 	/* Enable the output (set up the crtc or create a
 	 * window representing the output, set up the
@@ -6828,6 +6897,8 @@ weston_output_release(struct weston_output *output)
 	if (output->enabled)
 		weston_compositor_remove_output(output);
 
+	weston_color_profile_unref(output->color_profile);
+
 	pixman_region32_fini(&output->region);
 	wl_list_remove(&output->link);
 

man/weston.ini.man

@@ -545,6 +545,14 @@ An integer, 1 by default, typically configured as 2 or higher when needed,
 denoting the scaling multiplier for the output.
 .RE
 .TP 7
+.BI "icc_profile=" file
+If option
+.B color-management
+is true, load the given ICC file as the output color profile. This works only
+on DRM, headless, wayland, and x11 backends, and for remoting and pipewire
+outputs.
+.RE
+.TP 7
 .BI "seat=" name
 The logical seat name that this output should be associated with. If this
 is set then the seat's input will be confined to the output that has the seat