diff --git a/source/blender/imbuf/intern/jp2.c b/source/blender/imbuf/intern/jp2.c
index ff0aeb068e2..3d04b8ee184 100644
--- a/source/blender/imbuf/intern/jp2.c
+++ b/source/blender/imbuf/intern/jp2.c
@@ -108,6 +108,13 @@ static void info_callback(const char *msg, void *client_data)
 		     i++, _rect += 4)                                                 \
 		{                                                                     \
 
+#   define PIXEL_LOOPER_BEGIN_CHANNELS(_rect, _channels)                      \
+	for (y = h - 1; y != (unsigned int)(-1); y--) {                           \
+		for (i = y * w, i_next = (y + 1) * w;                                 \
+		     i < i_next;                                                      \
+		     i++, _rect += _channels)                                         \
+		{                                                                     \
+
 #   define PIXEL_LOOPER_END \
 	} \
 	} (void)0 \
@@ -663,76 +670,198 @@ static opj_image_t *ibuftoimage(ImBuf *ibuf, opj_cparameters_t *parameters)
 	}
 	
 	if (rect_float) {
+		int channels_in_float = ibuf->channels ? ibuf->channels : 4;
+
 		switch (prec) {
 			case 8: /* Convert blenders float color channels to 8, 12 or 16bit ints */
 				if (numcomps == 4) {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[2]));
-						a[i] = DOWNSAMPLE_FLOAT_TO_8BIT(from_straight[3]);
+					if (channels_in_float == 4) {
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[2]));
+							a[i] = DOWNSAMPLE_FLOAT_TO_8BIT(from_straight[3]);
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[2]));
+							a[i] = 255;
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+							a[i] = 255;
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				else {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[2]));
+					if (channels_in_float == 4) {
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(from_straight[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_8BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				break;
 			
 			case 12:
 				if (numcomps == 4) {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[2]));
-						a[i] = DOWNSAMPLE_FLOAT_TO_12BIT(from_straight[3]);
+					if (channels_in_float == 4) {
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[2]));
+							a[i] = DOWNSAMPLE_FLOAT_TO_12BIT(from_straight[3]);
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[2]));
+							a[i] = 4095;
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+							a[i] = 4095;
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				else {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[2]));
+					if (channels_in_float == 4) {
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(from_straight[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_12BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				break;
 
 			case 16:
 				if (numcomps == 4) {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[2]));
-						a[i] = DOWNSAMPLE_FLOAT_TO_16BIT(from_straight[3]);
+					if (channels_in_float == 4){
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[2]));
+							a[i] = DOWNSAMPLE_FLOAT_TO_16BIT(from_straight[3]);
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[2]));
+							a[i] = 65535;
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+							a[i] = 65535;
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				else {
-					PIXEL_LOOPER_BEGIN(rect_float)
-					{
-						premul_to_straight_v4_v4(from_straight, rect_float);
-						r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[0]));
-						g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[1]));
-						b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[2]));
+					if (channels_in_float == 4) {
+						PIXEL_LOOPER_BEGIN(rect_float)
+						{
+							premul_to_straight_v4_v4(from_straight, rect_float);
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(from_straight[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else if (channels_in_float == 3) {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 3)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[1]));
+							b[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[2]));
+						}
+						PIXEL_LOOPER_END;
+					}
+					else {
+						PIXEL_LOOPER_BEGIN_CHANNELS(rect_float, 1)
+						{
+							r[i] = DOWNSAMPLE_FLOAT_TO_16BIT(chanel_colormanage_cb(rect_float[0]));
+							g[i] = b[i] = r[i];
+						}
+						PIXEL_LOOPER_END;
 					}
-					PIXEL_LOOPER_END;
 				}
 				break;
 		}
diff --git a/source/blender/imbuf/intern/png.c b/source/blender/imbuf/intern/png.c
index cc73f688e70..68385f22a7a 100644
--- a/source/blender/imbuf/intern/png.c
+++ b/source/blender/imbuf/intern/png.c
@@ -133,6 +133,7 @@ int imb_savepng(struct ImBuf *ibuf, const char *name, int flags)
 
 	bool is_16bit  = (ibuf->ftype & PNG_16BIT);
 	bool has_float = (ibuf->rect_float != NULL);
+	int channels_in_float = ibuf->channels ? ibuf->channels : 4;
 
 	float (*chanel_colormanage_cb)(float);
 
@@ -156,7 +157,7 @@ int imb_savepng(struct ImBuf *ibuf, const char *name, int flags)
 
 	bytesperpixel = (ibuf->planes + 7) >> 3;
 	if ((bytesperpixel > 4) || (bytesperpixel == 2)) {
-		printf("imb_savepng: Cunsupported bytes per pixel: %d for file: '%s'\n", bytesperpixel, name);
+		printf("imb_savepng: Unsupported bytes per pixel: %d for file: '%s'\n", bytesperpixel, name);
 		return (0);
 	}
 
@@ -203,13 +204,32 @@ int imb_savepng(struct ImBuf *ibuf, const char *name, int flags)
 			color_type = PNG_COLOR_TYPE_RGBA;
 			if (is_16bit) {
 				if (has_float) {
-					for (i = ibuf->x * ibuf->y; i > 0; i--) {
-						premul_to_straight_v4_v4(from_straight, from_float);
-						to16[0] = ftoshort(chanel_colormanage_cb(from_straight[0]));
-						to16[1] = ftoshort(chanel_colormanage_cb(from_straight[1]));
-						to16[2] = ftoshort(chanel_colormanage_cb(from_straight[2]));
-						to16[3] = ftoshort(chanel_colormanage_cb(from_straight[3]));
-						to16 += 4; from_float += 4;
+					if (channels_in_float == 4) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							premul_to_straight_v4_v4(from_straight, from_float);
+							to16[0] = ftoshort(chanel_colormanage_cb(from_straight[0]));
+							to16[1] = ftoshort(chanel_colormanage_cb(from_straight[1]));
+							to16[2] = ftoshort(chanel_colormanage_cb(from_straight[2]));
+							to16[3] = ftoshort(chanel_colormanage_cb(from_straight[3]));
+							to16 += 4; from_float += 4;
+						}
+					}
+					else if (channels_in_float == 3) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							to16[0] = ftoshort(chanel_colormanage_cb(from_float[0]));
+							to16[1] = ftoshort(chanel_colormanage_cb(from_float[1]));
+							to16[2] = ftoshort(chanel_colormanage_cb(from_float[2]));
+							to16[3] = 65535;
+							to16 += 4; from_float += 3;
+						}
+					}
+					else {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							to16[0] = ftoshort(chanel_colormanage_cb(from_float[0]));
+							to16[2] = to16[1] = to16[0];
+							to16[3] = 65535;
+							to16 += 4; from_float++;
+						}
 					}
 				}
 				else {
@@ -236,12 +256,29 @@ int imb_savepng(struct ImBuf *ibuf, const char *name, int flags)
 			color_type = PNG_COLOR_TYPE_RGB;
 			if (is_16bit) {
 				if (has_float) {
-					for (i = ibuf->x * ibuf->y; i > 0; i--) {
-						premul_to_straight_v4_v4(from_straight, from_float);
-						to16[0] = ftoshort(chanel_colormanage_cb(from_straight[0]));
-						to16[1] = ftoshort(chanel_colormanage_cb(from_straight[1]));
-						to16[2] = ftoshort(chanel_colormanage_cb(from_straight[2]));
-						to16 += 3; from_float += 4;
+					if (channels_in_float == 4) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							premul_to_straight_v4_v4(from_straight, from_float);
+							to16[0] = ftoshort(chanel_colormanage_cb(from_straight[0]));
+							to16[1] = ftoshort(chanel_colormanage_cb(from_straight[1]));
+							to16[2] = ftoshort(chanel_colormanage_cb(from_straight[2]));
+							to16 += 3; from_float += 4;
+						}
+					}
+					else if (channels_in_float == 3) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							to16[0] = ftoshort(chanel_colormanage_cb(from_float[0]));
+							to16[1] = ftoshort(chanel_colormanage_cb(from_float[1]));
+							to16[2] = ftoshort(chanel_colormanage_cb(from_float[2]));
+							to16 += 3; from_float += 3;
+						}
+					}
+					else {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							to16[0] = ftoshort(chanel_colormanage_cb(from_float[0]));
+							to16[2] = to16[1] = to16[0];
+							to16 += 3; from_float++;
+						}
 					}
 				}
 				else {
@@ -266,10 +303,31 @@ int imb_savepng(struct ImBuf *ibuf, const char *name, int flags)
 			color_type = PNG_COLOR_TYPE_GRAY;
 			if (is_16bit) {
 				if (has_float) {
-					for (i = ibuf->x * ibuf->y; i > 0; i--) {
-						premul_to_straight_v4_v4(from_straight, from_float);
-						to16[0] = ftoshort(chanel_colormanage_cb(from_straight[0]));
-						to16++; from_float += 4;
+					float rgb[3];
+					if (channels_in_float == 4) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							premul_to_straight_v4_v4(from_straight, from_float);
+							rgb[0] = chanel_colormanage_cb(from_straight[0]);
+							rgb[1] = chanel_colormanage_cb(from_straight[1]);
+							rgb[2] = chanel_colormanage_cb(from_straight[2]);
+							to16[0] = ftoshort(rgb_to_bw(rgb));
+							to16++; from_float += 4;
+						}
+					}
+					else if (channels_in_float == 3) {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							rgb[0] = chanel_colormanage_cb(from_float[0]);
+							rgb[1] = chanel_colormanage_cb(from_float[1]);
+							rgb[2] = chanel_colormanage_cb(from_float[2]);
+							to16[0] = ftoshort(rgb_to_bw(rgb));
+							to16++; from_float += 3;
+						}
+					}
+					else {
+						for (i = ibuf->x * ibuf->y; i > 0; i--) {
+							to16[0] = ftoshort(chanel_colormanage_cb(from_float[0]));
+							to16++; from_float++;
+						}
 					}
 				}
 				else {