White Balance modifier for the VSE

This snippet creates a white balance modifier for the video sequence editor. It is useful for everyone who likes to set a new white point in the video source (easily via the eyedropper). Just select a point in the source file where you know that it should be white. The algorithm will then shift the colors towards your new white point.

See attached the image for a quick demo.

{F270576}

Reviewers: psy-fi

Reviewed By: psy-fi

Subscribers: Blendify

Projects: #bf_blender

Differential Revision: https://developer.blender.org/D1698

7 files changed, 121 insertions, 6 deletions

diff --git a/source/blender/blenkernel/BKE_sequencer.h b/source/blender/blenkernel/BKE_sequencer.h
index 3f2712e0ae1..4582d113941 100644
--- a/source/blender/blenkernel/BKE_sequencer.h
+++ b/source/blender/blenkernel/BKE_sequencer.h
@@ -458,7 +458,7 @@ typedef struct SequenceModifierTypeInfo {
 
 const struct SequenceModifierTypeInfo *BKE_sequence_modifier_type_info_get(int type);
 
-struct SequenceModifierData *BKE_sequence_modifier_new(struct Sequence *seq, const char *name, int type);
+struct SequenceModifierData *BKE_sequence_modifier_new(struct Sequence *seq, const char *name, int type, struct Scene *scene);
 bool BKE_sequence_modifier_remove(struct Sequence *seq, struct SequenceModifierData *smd);
 void BKE_sequence_modifier_clear(struct Sequence *seq);
 void BKE_sequence_modifier_free(struct SequenceModifierData *smd);
diff --git a/source/blender/blenkernel/intern/seqmodifier.c b/source/blender/blenkernel/intern/seqmodifier.c
index 07242aa2f6e..f12faacd677 100644
--- a/source/blender/blenkernel/intern/seqmodifier.c
+++ b/source/blender/blenkernel/intern/seqmodifier.c
@@ -42,12 +42,14 @@
 #include "BLT_translation.h"
 
 #include "DNA_sequence_types.h"
+#include "DNA_scene_types.h"
 
 #include "BKE_colortools.h"
 #include "BKE_sequencer.h"
 
 #include "IMB_imbuf.h"
 #include "IMB_imbuf_types.h"
+#include "IMB_colormanagement.h"
 
 static SequenceModifierTypeInfo *modifiersTypes[NUM_SEQUENCE_MODIFIER_TYPES];
 static bool modifierTypesInit = false;
@@ -173,6 +175,87 @@ static SequenceModifierTypeInfo seqModifier_ColorBalance = {
 	colorBalance_apply                                     /* apply */
 };
 
+/* **** White Balance Modifier **** */
+
+static void whiteBalance_init_data(SequenceModifierData *smd)
+{
+	WhiteBalanceModifierData *cbmd = (WhiteBalanceModifierData *) smd;
+	copy_v3_fl(cbmd->white_value, 1.0f);
+}
+
+typedef struct WhiteBalanceThreadData {
+	struct ColorSpace* colorspace;
+	float white[3];
+} WhiteBalanceThreadData;
+
+static void whiteBalance_apply_threaded(int width, int height, unsigned char *rect, float *rect_float,
+                                        unsigned char *mask_rect, float *mask_rect_float, void *data_v)
+{
+	int x, y;
+	float multiplier[3];
+
+	WhiteBalanceThreadData *data = (WhiteBalanceThreadData *) data_v;
+
+	multiplier[0] = 1.0f/data->white[0];
+	multiplier[1] = 1.0f/data->white[1];
+	multiplier[2] = 1.0f/data->white[2];
+
+	for (y = 0; y < height; y++) {
+		for (x = 0; x < width; x++) {
+			int pixel_index = (y * width + x) * 4;
+			float result[3], mask[3] = {1.0f, 1.0f, 1.0f};
+
+			if (rect_float)
+				copy_v3_v3(result, rect_float + pixel_index);
+			else
+			{
+				straight_uchar_to_premul_float(result, rect + pixel_index);
+				IMB_colormanagement_colorspace_to_scene_linear_v3(result, data->colorspace);
+			}
+
+			mul_v3_v3(result, multiplier);
+
+			if (mask_rect_float)
+				copy_v3_v3(mask, mask_rect_float + pixel_index);
+			else if (mask_rect)
+				rgb_uchar_to_float(mask, mask_rect + pixel_index);
+
+			result[0] = result[0] * (1.0f - mask[0]) + result[0] * mask[0];
+			result[1] = result[1] * (1.0f - mask[1]) + result[1] * mask[1];
+			result[2] = result[2] * (1.0f - mask[2]) + result[2] * mask[2];
+
+			if (rect_float)
+				copy_v3_v3(rect_float + pixel_index, result);
+			else
+				IMB_colormanagement_scene_linear_to_colorspace_v3(result, data->colorspace);
+				premul_float_to_straight_uchar(rect + pixel_index, result);
+			}
+	}
+}
+
+static void whiteBalance_apply(SequenceModifierData *smd, ImBuf *ibuf, ImBuf *mask)
+{
+	WhiteBalanceThreadData data;
+	WhiteBalanceModifierData *wbmd = (WhiteBalanceModifierData *) smd;
+
+	copy_v3_v3(data.white, wbmd->white_value);
+	IMB_colormanagement_display_to_scene_linear_v3(data.white,
+	                                               IMB_colormanagement_display_get_named(wbmd->modifier.scene->display_settings.display_device));
+	data.colorspace = ibuf->rect_colorspace;
+
+	modifier_apply_threaded(ibuf, mask, whiteBalance_apply_threaded, &data);
+}
+
+static SequenceModifierTypeInfo seqModifier_WhiteBalance = {
+	CTX_N_(BLT_I18NCONTEXT_ID_SEQUENCE, "White Balance"),  /* name */
+	"WhiteBalanceModifierData",                            /* struct_name */
+	sizeof(WhiteBalanceModifierData),                      /* struct_size */
+	whiteBalance_init_data,                                /* init_data */
+	NULL,                                                  /* free_data */
+	NULL,                                                  /* copy_data */
+	whiteBalance_apply                                     /* apply */
+};
+
 /* **** Curves Modifier **** */
 
 static void curves_init_data(SequenceModifierData *smd)
@@ -559,6 +642,7 @@ static void sequence_modifier_type_info_init(void)
 	INIT_TYPE(HueCorrect);
 	INIT_TYPE(BrightContrast);
 	INIT_TYPE(Mask);
+	INIT_TYPE(WhiteBalance);
 
 #undef INIT_TYPE
 }
@@ -573,7 +657,7 @@ const SequenceModifierTypeInfo *BKE_sequence_modifier_type_info_get(int type)
 	return modifiersTypes[type];
 }
 
-SequenceModifierData *BKE_sequence_modifier_new(Sequence *seq, const char *name, int type)
+SequenceModifierData *BKE_sequence_modifier_new(Sequence *seq, const char *name, int type, struct Scene *scene)
 {
 	SequenceModifierData *smd;
 	const SequenceModifierTypeInfo *smti = BKE_sequence_modifier_type_info_get(type);
@@ -582,6 +666,7 @@ SequenceModifierData *BKE_sequence_modifier_new(Sequence *seq, const char *name,
 
 	smd->type = type;
 	smd->flag |= SEQUENCE_MODIFIER_EXPANDED;
+	smd->scene = scene;
 
 	if (!name || !name[0])
 		BLI_strncpy(smd->name, smti->name, sizeof(smd->name));
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 30faa3709ba..a3bf673d5fa 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -5486,6 +5486,7 @@ static void lib_link_sequence_modifiers(FileData *fd, Scene *scene, ListBase *lb
 	for (smd = lb->first; smd; smd = smd->next) {
 		if (smd->mask_id)
 			smd->mask_id = newlibadr_us(fd, scene->id.lib, smd->mask_id);
+		smd->scene = scene;
 	}
 }
 
diff --git a/source/blender/blenloader/intern/versioning_260.c b/source/blender/blenloader/intern/versioning_260.c
index 77a4aefb7ac..027c3eb9fbf 100644
--- a/source/blender/blenloader/intern/versioning_260.c
+++ b/source/blender/blenloader/intern/versioning_260.c
@@ -1503,7 +1503,7 @@ void blo_do_versions_260(FileData *fd, Library *UNUSED(lib), Main *main)
 						SequenceModifierData *smd;
 						ColorBalanceModifierData *cbmd;
 
-						smd = BKE_sequence_modifier_new(seq, NULL, seqModifierType_ColorBalance);
+						smd = BKE_sequence_modifier_new(seq, NULL, seqModifierType_ColorBalance, scene);
 						cbmd = (ColorBalanceModifierData *) smd;
 
 						cbmd->color_balance = *strip->color_balance;
diff --git a/source/blender/editors/space_sequencer/sequencer_modifier.c b/source/blender/editors/space_sequencer/sequencer_modifier.c
index 5d4ea47452e..713e1618e39 100644
--- a/source/blender/editors/space_sequencer/sequencer_modifier.c
+++ b/source/blender/editors/space_sequencer/sequencer_modifier.c
@@ -71,7 +71,7 @@ static int strip_modifier_add_exec(bContext *C, wmOperator *op)
 	Sequence *seq = BKE_sequencer_active_get(scene);
 	int type = RNA_enum_get(op->ptr, "type");
 
-	BKE_sequence_modifier_new(seq, NULL, type);
+	BKE_sequence_modifier_new(seq, NULL, type, scene);
 
 	BKE_sequence_invalidate_cache(scene, seq);
 	WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER, scene);
diff --git a/source/blender/makesdna/DNA_sequence_types.h b/source/blender/makesdna/DNA_sequence_types.h
index e5c102b1d2d..bb49419b2ac 100644
--- a/source/blender/makesdna/DNA_sequence_types.h
+++ b/source/blender/makesdna/DNA_sequence_types.h
@@ -307,11 +307,12 @@ typedef struct SequenceModifierData {
 	int type, flag;
 	char name[64]; /* MAX_NAME */
 
-	/* mask input, either sequence or maks ID */
+	/* mask input, either sequence or mask ID */
 	int mask_input_type, pad;
 
 	struct Sequence *mask_sequence;
 	struct Mask     *mask_id;
+	struct Scene    *scene;
 } SequenceModifierData;
 
 typedef struct ColorBalanceModifierData {
@@ -344,6 +345,13 @@ typedef struct SequencerMaskModifierData {
 	SequenceModifierData modifier;
 } SequencerMaskModifierData;
 
+typedef struct WhiteBalanceModifierData {
+	SequenceModifierData modifier;
+
+	float white_value[3];
+	float pad;
+} WhiteBalanceModifierData;
+
 /* ***************** Scopes ****************** */
 
 typedef struct SequencerScopes {
@@ -519,6 +527,7 @@ enum {
 	seqModifierType_HueCorrect     = 3,
 	seqModifierType_BrightContrast = 4,
 	seqModifierType_Mask           = 5,
+	seqModifierType_WhiteBalance   = 6,
 
 	NUM_SEQUENCE_MODIFIER_TYPES
 };
diff --git a/source/blender/makesrna/intern/rna_sequencer.c b/source/blender/makesrna/intern/rna_sequencer.c
index 1fb57fc1d11..d9d56adffae 100644
--- a/source/blender/makesrna/intern/rna_sequencer.c
+++ b/source/blender/makesrna/intern/rna_sequencer.c
@@ -66,6 +66,7 @@ EnumPropertyItem rna_enum_sequence_modifier_type_items[] = {
 	{seqModifierType_HueCorrect, "HUE_CORRECT", ICON_NONE, "Hue Correct", ""},
 	{seqModifierType_BrightContrast, "BRIGHT_CONTRAST", ICON_NONE, "Bright/Contrast", ""},
 	{seqModifierType_Mask, "MASK", ICON_NONE, "Mask", ""},
+	{seqModifierType_WhiteBalance, "WHITE_BALANCE", ICON_NONE, "White Balance", ""},
 	{0, NULL, 0, NULL, NULL}
 };
 
@@ -955,6 +956,8 @@ static StructRNA *rna_SequenceModifier_refine(struct PointerRNA *ptr)
 			return &RNA_HueCorrectModifier;
 		case seqModifierType_BrightContrast:
 			return &RNA_BrightContrastModifier;
+		case seqModifierType_WhiteBalance:
+			return &RNA_WhiteBalanceModifier;
 		default:
 			return &RNA_SequenceModifier;
 	}
@@ -1043,7 +1046,7 @@ static SequenceModifierData *rna_Sequence_modifier_new(Sequence *seq, bContext *
 		Scene *scene = CTX_data_scene(C);
 		SequenceModifierData *smd;
 
-		smd = BKE_sequence_modifier_new(seq, name, type);
+		smd = BKE_sequence_modifier_new(seq, name, type, scene);
 
 		BKE_sequence_invalidate_cache_for_modifier(scene, seq);
 
@@ -2496,6 +2499,22 @@ static void rna_def_colorbalance_modifier(BlenderRNA *brna)
 	RNA_def_property_update(prop, NC_SCENE | ND_SEQUENCER, "rna_SequenceModifier_update");
 }
 
+static void rna_def_whitebalance_modifier(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	PropertyRNA *prop;
+
+	srna = RNA_def_struct(brna, "WhiteBalanceModifier", "SequenceModifier");
+	RNA_def_struct_sdna(srna, "WhiteBalanceModifierData");
+	RNA_def_struct_ui_text(srna, "WhiteBalanceModifier", "White balance modifier for sequence strip");
+
+	prop = RNA_def_property(srna, "white_value", PROP_FLOAT, PROP_COLOR_GAMMA);
+	RNA_def_property_range(prop, 0.0, 1.0);
+	RNA_def_property_float_sdna(prop, NULL, "white_value");
+	RNA_def_property_ui_text(prop, "White value", "This color defines white in the strip");
+	RNA_def_property_update(prop, NC_SCENE | ND_SEQUENCER, "rna_SequenceModifier_update");
+}
+
 static void rna_def_curves_modifier(BlenderRNA *brna)
 {
 	StructRNA *srna;
@@ -2558,6 +2577,7 @@ static void rna_def_modifiers(BlenderRNA *brna)
 	rna_def_curves_modifier(brna);
 	rna_def_hue_modifier(brna);
 	rna_def_brightcontrast_modifier(brna);
+	rna_def_whitebalance_modifier(brna);
 }
 
 void RNA_def_sequencer(BlenderRNA *brna)