Remove histogram color profile

Aside from being coded with the ass (entirely copy-pasted), the histogram color profile is useless since the histogram is grabbed in display RGB. If we want to display the histogram in pipe RGB, then we can convert display to pipe RGB but if RGB got clipped in display, then we convert clipped signal.

The whole thing is misleading and was used in overexposed module, which completely voids its purpose. Say you display histogram in Rec 2020 (super large), but your display is sRGB (super small), then you clip in sRGB at 100%, but converting back to Rec 2020, your 100% becomes 90 % or something, and the scope shows no overexposure at all.

That's bullshit coded by idiots. Not sure why it took me 4 years to spot it.

data/kernels/basic.cl

@@ -2657,7 +2657,7 @@ typedef enum dt_clipping_preview_mode_t
 } dt_clipping_preview_mode_t;
 
 kernel void
-overexposed (read_only image2d_t in, write_only image2d_t out, read_only image2d_t tmp, const int width, const int height,
+overexposed (read_only image2d_t in, write_only image2d_t out, const int width, const int height,
              const float lower, const float upper, const float4 lower_color, const float4 upper_color,
              constant dt_colorspaces_iccprofile_info_cl_t *profile_info,
             read_only image2d_t lut, const int use_work_profile, dt_clipping_preview_mode_t mode)
@@ -2668,14 +2668,13 @@ overexposed (read_only image2d_t in, write_only image2d_t out, read_only image2d
   if(x >= width || y >= height) return;
 
   float4 pixel = read_imagef(in, sampleri, (int2)(x, y));
-  float4 pixel_tmp = read_imagef(tmp, sampleri, (int2)(x, y));
 
   if(mode == DT_CLIPPING_PREVIEW_ANYRGB)
   {
-    if(pixel_tmp.x >= upper || pixel_tmp.y >= upper || pixel_tmp.z >= upper)
+    if(pixel.x >= upper || pixel.y >= upper || pixel.z >= upper)
       pixel.xyz = upper_color.xyz;
 
-    else if(pixel_tmp.x <= lower && pixel_tmp.y <= lower && pixel_tmp.z <= lower)
+    else if(pixel.x <= lower && pixel.y <= lower && pixel.z <= lower)
       pixel.xyz = lower_color.xyz;
 
   }
@@ -2694,14 +2693,14 @@ overexposed (read_only image2d_t in, write_only image2d_t out, read_only image2d
     else
     {
       float4 saturation = { 0.f, 0.f, 0.f, 0.f};
-      saturation = pixel_tmp - (float4)luminance;
-      saturation = native_sqrt(saturation * saturation / ((float4)(luminance * luminance) + pixel_tmp * pixel_tmp));
+      saturation = pixel - (float4)luminance;
+      saturation = native_sqrt(saturation * saturation / ((float4)(luminance * luminance) + pixel * pixel));
 
       if(saturation.x > upper || saturation.y > upper || saturation.z > upper ||
-         pixel_tmp.x >= upper || pixel_tmp.y >= upper || pixel_tmp.z >= upper)
+         pixel.x >= upper || pixel.y >= upper || pixel.z >= upper)
         pixel.xyz = upper_color.xyz;
 
-      else if(pixel_tmp.x <= lower && pixel_tmp.y <= lower && pixel_tmp.z <= lower)
+      else if(pixel.x <= lower && pixel.y <= lower && pixel.z <= lower)
         pixel.xyz = lower_color.xyz;
     }
   }
@@ -2722,14 +2721,14 @@ overexposed (read_only image2d_t in, write_only image2d_t out, read_only image2d
     if(luminance < upper && luminance > lower)
     {
       float4 saturation = { 0.f, 0.f, 0.f, 0.f};
-      saturation = pixel_tmp - (float4)luminance;
-      saturation = native_sqrt(saturation * saturation / ((float4)(luminance * luminance) + pixel_tmp * pixel_tmp));
+      saturation = pixel - (float4)luminance;
+      saturation = native_sqrt(saturation * saturation / ((float4)(luminance * luminance) + pixel * pixel));
 
       if(saturation.x > upper || saturation.y > upper || saturation.z > upper ||
-         pixel_tmp.x >= upper || pixel_tmp.y >= upper || pixel_tmp.z >= upper)
+         pixel.x >= upper || pixel.y >= upper || pixel.z >= upper)
         pixel.xyz = upper_color.xyz;
 
-      else if(pixel_tmp.x <= lower && pixel_tmp.y <= lower && pixel_tmp.z <= lower)
+      else if(pixel.x <= lower && pixel.y <= lower && pixel.z <= lower)
         pixel.xyz = lower_color.xyz;
     }
   }

src/common/colorspaces.c

@@ -1490,13 +1490,10 @@ dt_colorspaces_t *dt_colorspaces_init()
   // init display profile and softproof/gama checking from conf
   res->display_type = dt_conf_get_int("ui_last/color/display_type");
   res->softproof_type = dt_conf_get_int("ui_last/color/softproof_type");
-  res->histogram_type = dt_conf_get_int("ui_last/color/histogram_type");
   const char *tmp = dt_conf_get_string_const("ui_last/color/display_filename");
   g_strlcpy(res->display_filename, tmp, sizeof(res->display_filename));
   tmp = dt_conf_get_string_const("ui_last/color/softproof_filename");
   g_strlcpy(res->softproof_filename, tmp, sizeof(res->softproof_filename));
-  tmp = dt_conf_get_string_const("ui_last/color/histogram_filename");
-  g_strlcpy(res->histogram_filename, tmp, sizeof(res->histogram_filename));
   res->display_intent = dt_conf_get_int("ui_last/color/display_intent");
   res->softproof_intent = dt_conf_get_int("ui_last/color/softproof_intent");
   res->mode = dt_conf_get_int("ui_last/color/mode");
@@ -1513,11 +1510,6 @@ dt_colorspaces_t *dt_colorspaces_init()
          && (!res->softproof_filename[0] || !g_file_test(res->softproof_filename, G_FILE_TEST_IS_REGULAR))))
     res->softproof_type = DT_COLORSPACE_SRGB;
 
-  if((unsigned int)res->histogram_type >= DT_COLORSPACE_LAST
-     || (res->histogram_type == DT_COLORSPACE_FILE
-         && (!res->histogram_filename[0] || !g_file_test(res->histogram_filename, G_FILE_TEST_IS_REGULAR))))
-    res->histogram_type = DT_COLORSPACE_SRGB;
-
   // temporary list of profiles to be added, we keep this separate to be able to sort it before adding
   GList *temp_profiles;
 
@@ -1559,20 +1551,6 @@ dt_colorspaces_t *dt_colorspaces_init()
                "output profile `%s' color space `%c%c%c%c' not supported for work or histogram profile\n",
                prof->name, (char)(color_space >> 24), (char)(color_space >> 16), (char)(color_space >> 8),
                (char)(color_space));
-
-      if(res->histogram_type == prof->type
-         && (prof->type != DT_COLORSPACE_FILE
-             || dt_colorspaces_is_profile_equal(prof->filename, res->histogram_filename)))
-      {
-        // bad histogram profile selected, we must reset it to sRGB
-        const char *name = dt_colorspaces_get_name(prof->type, prof->filename);
-        dt_control_log(_("profile `%s' not usable as histogram profile. it has been replaced by sRGB!"), name);
-        fprintf(stderr,
-                "[colorspaces] profile `%s' not usable as histogram profile. it has been replaced by sRGB!\n",
-                name);
-        res->histogram_type = DT_COLORSPACE_SRGB;
-        res->histogram_filename[0] = '\0';
-      }
     }
   }
   res->profiles = g_list_concat(res->profiles, temp_profiles);
@@ -1590,10 +1568,8 @@ void dt_colorspaces_cleanup(dt_colorspaces_t *self)
   // remember display profile and softproof/gama checking from conf
   dt_conf_set_int("ui_last/color/display_type", self->display_type);
   dt_conf_set_int("ui_last/color/softproof_type", self->softproof_type);
-  dt_conf_set_int("ui_last/color/histogram_type", self->histogram_type);
   dt_conf_set_string("ui_last/color/display_filename", self->display_filename);
   dt_conf_set_string("ui_last/color/softproof_filename", self->softproof_filename);
-  dt_conf_set_string("ui_last/color/histogram_filename", self->histogram_filename);
   dt_conf_set_int("ui_last/color/display_intent", self->display_intent);
   dt_conf_set_int("ui_last/color/softproof_intent", self->softproof_intent);
   dt_conf_set_int("ui_last/color/mode", self->mode);

src/common/colorspaces.h

@@ -153,10 +153,8 @@ typedef struct dt_colorspaces_t
   // the current set of selected profiles
   dt_colorspaces_color_profile_type_t display_type;
   dt_colorspaces_color_profile_type_t softproof_type;
-  dt_colorspaces_color_profile_type_t histogram_type;
   char display_filename[512];
   char softproof_filename[512];
-  char histogram_filename[512];
   dt_iop_color_intent_t display_intent;
   dt_iop_color_intent_t softproof_intent;
 

src/common/iop_profile.c

@@ -884,15 +884,6 @@ dt_ioppr_set_pipe_output_profile_info(struct dt_develop_t *dev,
   return profile_info;
 }
 
-dt_iop_order_iccprofile_info_t *dt_ioppr_get_histogram_profile_info(struct dt_develop_t *dev)
-{
-  dt_colorspaces_color_profile_type_t histogram_profile_type;
-  const char *histogram_profile_filename;
-  dt_ioppr_get_histogram_profile_type(&histogram_profile_type, &histogram_profile_filename);
-  return dt_ioppr_add_profile_info_to_list(dev, histogram_profile_type, histogram_profile_filename,
-                                           DT_INTENT_RELATIVE_COLORIMETRIC);
-}
-
 dt_iop_order_iccprofile_info_t *dt_ioppr_get_pipe_work_profile_info(struct dt_dev_pixelpipe_t *pipe)
 {
   return pipe->work_profile_info;
@@ -1022,33 +1013,6 @@ void dt_ioppr_get_export_profile_type(struct dt_develop_t *dev,
     fprintf(stderr, "[dt_ioppr_get_export_profile_type] can't find colorout iop\n");
 }
 
-void dt_ioppr_get_histogram_profile_type(dt_colorspaces_color_profile_type_t *profile_type,
-                                         const char **profile_filename)
-{
-  const dt_colorspaces_color_mode_t mode = darktable.color_profiles->mode;
-
-  // if in gamut check use soft proof
-  if(mode != DT_PROFILE_NORMAL || darktable.color_profiles->histogram_type == DT_COLORSPACE_SOFTPROOF)
-  {
-    *profile_type = darktable.color_profiles->softproof_type;
-    *profile_filename = darktable.color_profiles->softproof_filename;
-  }
-  else if(darktable.color_profiles->histogram_type == DT_COLORSPACE_WORK)
-  {
-    dt_ioppr_get_work_profile_type(darktable.develop, profile_type, profile_filename);
-  }
-  else if(darktable.color_profiles->histogram_type == DT_COLORSPACE_EXPORT)
-  {
-    dt_ioppr_get_export_profile_type(darktable.develop, profile_type, profile_filename);
-  }
-  else
-  {
-    *profile_type = darktable.color_profiles->histogram_type;
-    *profile_filename = darktable.color_profiles->histogram_filename;
-  }
-}
-
-
 __DT_CLONE_TARGETS__
 void dt_ioppr_transform_image_colorspace(struct dt_iop_module_t *self, const float *const image_in,
                                          float *const image_out, const int width, const int height,

src/develop/pixelpipe_hb.c

@@ -754,7 +754,6 @@ static void pixelpipe_picker_cl(int devid, dt_iop_module_t *module, dt_dev_pixel
 static void _pixelpipe_pick_from_image(dt_iop_module_t *module,
                                        const float *const pixel, const dt_iop_roi_t *roi_in,
                                        const dt_iop_order_iccprofile_info_t *const display_profile,
-                                       const dt_iop_order_iccprofile_info_t *const histogram_profile,
                                        dt_colorpicker_sample_t *const sample)
 {
   if(sample->size == DT_LIB_COLORPICKER_SIZE_BOX)
@@ -796,9 +795,6 @@ static void _pixelpipe_pick_from_image(dt_iop_module_t *module,
     int converted_cst;
     dt_ioppr_transform_image_colorspace(module, picked_rgb[0], sample->lab[0], 3, 1, IOP_CS_RGB, IOP_CS_LAB,
                                         &converted_cst, display_profile);
-    if(display_profile && histogram_profile)
-      dt_ioppr_transform_image_colorspace_rgb(picked_rgb[0], sample->scope[0], 3, 1,
-                                              display_profile, histogram_profile, "primary picker");
   }
   else if(sample->size == DT_LIB_COLORPICKER_SIZE_POINT)
   {
@@ -809,9 +805,7 @@ static void _pixelpipe_pick_from_image(dt_iop_module_t *module,
     memcpy(sample->display[0], pixel + 4 * (roi_in->width * y + x), sizeof(dt_aligned_pixel_t));
     dt_ioppr_transform_image_colorspace(module, sample->display[0], sample->lab[0], 1, 1, IOP_CS_RGB, IOP_CS_LAB,
                                         &converted_cst, display_profile);
-    if(display_profile && histogram_profile)
-      dt_ioppr_transform_image_colorspace_rgb(sample->display[0], sample->scope[0], 1, 1,
-                                              display_profile, histogram_profile, "primary picker");
+
     for(dt_lib_colorpicker_statistic_t stat = 1; stat < DT_LIB_COLORPICKER_STATISTIC_N; stat++)
     {
       memcpy(sample->display[stat], sample->display[0], sizeof(dt_aligned_pixel_t));
@@ -824,7 +818,6 @@ static void _pixelpipe_pick_from_image(dt_iop_module_t *module,
 static void _pixelpipe_pick_samples(dt_develop_t *dev, dt_iop_module_t *module,
                                     const float *const input, const dt_iop_roi_t *roi_in)
 {
-  const dt_iop_order_iccprofile_info_t *const histogram_profile = dt_ioppr_get_histogram_profile_info(dev);
   const dt_iop_order_iccprofile_info_t *const display_profile
     = dt_ioppr_add_profile_info_to_list(dev, darktable.color_profiles->display_type,
                                         darktable.color_profiles->display_filename, INTENT_RELATIVE_COLORIMETRIC);
@@ -834,12 +827,12 @@ static void _pixelpipe_pick_samples(dt_develop_t *dev, dt_iop_module_t *module,
   {
     dt_colorpicker_sample_t *sample = samples->data;
     if(!sample->locked)
-      _pixelpipe_pick_from_image(module, input, roi_in, display_profile, histogram_profile, sample);
+      _pixelpipe_pick_from_image(module, input, roi_in, display_profile, sample);
     samples = g_slist_next(samples);
   }
 
   if(darktable.lib->proxy.colorpicker.picker_proxy)
-    _pixelpipe_pick_from_image(module, input, roi_in, display_profile, histogram_profile,
+    _pixelpipe_pick_from_image(module, input, roi_in, display_profile,
                                darktable.lib->proxy.colorpicker.primary_sample);
 }
 
@@ -2030,7 +2023,7 @@ static int dt_dev_pixelpipe_process_rec(dt_dev_pixelpipe_t *pipe, dt_develop_t *
     // benefit via a histogram.
     darktable.lib->proxy.histogram.process(darktable.lib->proxy.histogram.module, input,
                                            roi_in.width, roi_in.height,
-                                           display_profile, dt_ioppr_get_histogram_profile_info(dev));
+                                           display_profile, display_profile);
   }
 
   if(dt_atomic_get_int(&pipe->shutdown))

src/iop/colorzones.c

@@ -822,14 +822,14 @@ static void _draw_color_picker(dt_iop_module_t *self, cairo_t *cr, dt_iop_colorz
     GSList *samples = darktable.lib->proxy.colorpicker.live_samples;
     if(samples)
     {
-      const dt_iop_order_iccprofile_info_t *const histogram_profile
-          = dt_ioppr_get_histogram_profile_info(self->dev);
+      const dt_iop_order_iccprofile_info_t *const display_profile
+          = dt_ioppr_get_pipe_output_profile_info(self->dev->pipe);
       const dt_iop_order_iccprofile_info_t *const work_profile
           = dt_ioppr_get_iop_work_profile_info(self, self->dev->iop);
       dt_aligned_pixel_t pick_mean, pick_min, pick_max;
       int converted_cst;
 
-      if(work_profile && histogram_profile)
+      if(work_profile && display_profile)
       {
         dt_colorpicker_sample_t *sample = NULL;
         for(; samples; samples = g_slist_next(samples))
@@ -849,11 +849,11 @@ static void _draw_color_picker(dt_iop_module_t *self, cairo_t *cr, dt_iop_colorz
           }
           pick_mean[3] = pick_min[3] = pick_max[3] = 1.f;
 
-          dt_ioppr_transform_image_colorspace_rgb(pick_mean, pick_mean, 1, 1, histogram_profile, work_profile,
+          dt_ioppr_transform_image_colorspace_rgb(pick_mean, pick_mean, 1, 1, display_profile, work_profile,
                                                   "color zones");
-          dt_ioppr_transform_image_colorspace_rgb(pick_min, pick_min, 1, 1, histogram_profile, work_profile,
+          dt_ioppr_transform_image_colorspace_rgb(pick_min, pick_min, 1, 1, display_profile, work_profile,
                                                   "color zones");
-          dt_ioppr_transform_image_colorspace_rgb(pick_max, pick_max, 1, 1, histogram_profile, work_profile,
+          dt_ioppr_transform_image_colorspace_rgb(pick_max, pick_max, 1, 1, display_profile, work_profile,
                                                   "color zones");
 
           dt_ioppr_transform_image_colorspace(self, pick_mean, pick_mean, 1, 1, IOP_CS_RGB, IOP_CS_LAB,