avfilter/vf_blend: add freeze and heat modes

Signed-off-by: Paul B Mahol <onemda@gmail.com>

doc/filters.texi

@@ -4240,10 +4240,12 @@ Available values for component modes are:
 @item difference128
 @item divide
 @item dodge
+@item freeze
 @item exclusion
 @item glow
 @item hardlight
 @item hardmix
+@item heat
 @item lighten
 @item linearlight
 @item multiply

libavfilter/blend.h

@@ -56,6 +56,8 @@ enum BlendMode {
     BLEND_GLOW,
     BLEND_ADDITION128,
     BLEND_MULTIPLY128,
+    BLEND_HEAT,
+    BLEND_FREEZE,
     BLEND_NB
 };
 

libavfilter/vf_blend.c

@@ -76,9 +76,11 @@ typedef struct ThreadData {
     { "divide",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIVIDE},     0, 0, FLAGS, "mode" },\
     { "dodge",      "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DODGE},      0, 0, FLAGS, "mode" },\
     { "exclusion",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_EXCLUSION},  0, 0, FLAGS, "mode" },\
+    { "freeze",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_FREEZE},     0, 0, FLAGS, "mode" },\
     { "glow",       "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_GLOW},       0, 0, FLAGS, "mode" },\
     { "hardlight",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HARDLIGHT},  0, 0, FLAGS, "mode" },\
     { "hardmix",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HARDMIX},    0, 0, FLAGS, "mode" },\
+    { "heat",       "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HEAT},       0, 0, FLAGS, "mode" },\
     { "lighten",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_LIGHTEN},    0, 0, FLAGS, "mode" },\
     { "linearlight","", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_LINEARLIGHT},0, 0, FLAGS, "mode" },\
     { "multiply",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_MULTIPLY},   0, 0, FLAGS, "mode" },\
@@ -245,6 +247,8 @@ DEFINE_BLEND8(screen,     SCREEN(1, A, B))
 DEFINE_BLEND8(overlay,    (A < 128) ? MULTIPLY(2, A, B) : SCREEN(2, A, B))
 DEFINE_BLEND8(hardlight,  (B < 128) ? MULTIPLY(2, B, A) : SCREEN(2, B, A))
 DEFINE_BLEND8(hardmix,    (A < (255 - B)) ? 0: 255)
+DEFINE_BLEND8(heat,       (A == 0) ? 0 : 255 - FFMIN(((255 - B) * (255 - B)) / A, 255))
+DEFINE_BLEND8(freeze,     (B == 0) ? 0 : 255 - FFMIN(((255 - A) * (255 - A)) / B, 255))
 DEFINE_BLEND8(darken,     FFMIN(A, B))
 DEFINE_BLEND8(lighten,    FFMAX(A, B))
 DEFINE_BLEND8(divide,     av_clip_uint8(B == 0 ? 255 : 255 * A / B))
@@ -285,6 +289,8 @@ DEFINE_BLEND16(screen,     SCREEN(1, A, B))
 DEFINE_BLEND16(overlay,    (A < 32768) ? MULTIPLY(2, A, B) : SCREEN(2, A, B))
 DEFINE_BLEND16(hardlight,  (B < 32768) ? MULTIPLY(2, B, A) : SCREEN(2, B, A))
 DEFINE_BLEND16(hardmix,    (A < (65535 - B)) ? 0: 65535)
+DEFINE_BLEND16(heat,       (A == 0) ? 0 : 65535 - FFMIN(((65535 - B) * (65535 - B)) / A, 65535))
+DEFINE_BLEND16(freeze,     (B == 0) ? 0 : 65535 - FFMIN(((65535 - A) * (65535 - A)) / B, 65535))
 DEFINE_BLEND16(darken,     FFMIN(A, B))
 DEFINE_BLEND16(lighten,    FFMAX(A, B))
 DEFINE_BLEND16(divide,     av_clip_uint16(B == 0 ? 65535 : 65535 * A / B))
@@ -451,9 +457,11 @@ void ff_blend_init(FilterParams *param, int is_16bit)
     case BLEND_DIVIDE:     param->blend = is_16bit ? blend_divide_16bit     : blend_divide_8bit;     break;
     case BLEND_DODGE:      param->blend = is_16bit ? blend_dodge_16bit      : blend_dodge_8bit;      break;
     case BLEND_EXCLUSION:  param->blend = is_16bit ? blend_exclusion_16bit  : blend_exclusion_8bit;  break;
+    case BLEND_FREEZE:     param->blend = is_16bit ? blend_freeze_16bit     : blend_freeze_8bit;     break;
     case BLEND_GLOW:       param->blend = is_16bit ? blend_glow_16bit       : blend_glow_8bit;       break;
     case BLEND_HARDLIGHT:  param->blend = is_16bit ? blend_hardlight_16bit  : blend_hardlight_8bit;  break;
     case BLEND_HARDMIX:    param->blend = is_16bit ? blend_hardmix_16bit    : blend_hardmix_8bit;    break;
+    case BLEND_HEAT:       param->blend = is_16bit ? blend_heat_16bit       : blend_heat_8bit;       break;
     case BLEND_LIGHTEN:    param->blend = is_16bit ? blend_lighten_16bit    : blend_lighten_8bit;    break;
     case BLEND_LINEARLIGHT:param->blend = is_16bit ? blend_linearlight_16bit: blend_linearlight_8bit;break;
     case BLEND_MULTIPLY:   param->blend = is_16bit ? blend_multiply_16bit   : blend_multiply_8bit;   break;