diff --git a/internal/cgen/base/core-public.h b/internal/cgen/base/core-public.h
index dc7e7fb..f642fb7 100644
--- a/internal/cgen/base/core-public.h
+++ b/internal/cgen/base/core-public.h
@@ -197,6 +197,12 @@
 
 // --------
 
+// FourCC constants.
+
+// !! INSERT FourCCs.
+
+// --------
+
 // Flicks are a unit of time. One flick (frame-tick) is 1 / 705_600_000 of a
 // second. See https://github.com/OculusVR/Flicks
 typedef int64_t wuffs_base__flicks;
diff --git a/internal/cgen/cgen.go b/internal/cgen/cgen.go
index 52f9b3c..88d23ff 100644
--- a/internal/cgen/cgen.go
+++ b/internal/cgen/cgen.go
@@ -263,6 +263,19 @@
 
 func insertBaseAllPublicH(buf *buffer) error {
 	if err := expandBangBangInsert(buf, baseCorePublicH, map[string]func(*buffer) error{
+		"// !! INSERT FourCCs.\n": func(b *buffer) error {
+			for _, z := range builtin.FourCCs {
+				b.printf("// %s.\n#define WUFFS_BASE__FOURCC__%s 0x%02X%02X%02X%02X\n\n",
+					z[1],
+					strings.ToUpper(strings.TrimSpace(z[0])),
+					z[0][0],
+					z[0][1],
+					z[0][2],
+					z[0][3],
+				)
+			}
+			return nil
+		},
 		"// !! INSERT wuffs_base__status names.\n": func(b *buffer) error {
 			for _, z := range builtin.Statuses {
 				msg, _ := t.Unescape(z)
diff --git a/internal/cgen/data.go b/internal/cgen/data.go
index 926b4c2..832e20c 100644
--- a/internal/cgen/data.go
+++ b/internal/cgen/data.go
@@ -71,6 +71,8 @@
 	"// --------\n\n// A status is either NULL (meaning OK) or a string message. That message is\n// human-readable, for programmers, but it is not for end users. It is not\n// localized, and does not contain additional contextual information such as a\n// source filename.\n//\n// Status strings are statically allocated and should never be free'd. They can\n// be compared by the == operator and not just by strcmp.\n//\n// Statuses come in four categories:\n//  - OK:          the request was completed, successfully.\n//  - Warnings:    the request was completed, unsuccessfully.\n//  - Suspensions: the request was not completed, but can be re-tried.\n//  - Errors:      the request was not completed, permanently.\n//\n// When a function returns an incomplete status, a suspension means that that\n// function should be called again within a new context, such as after flushing\n// or re-filling an I/O buffer. An error means that an irrecoverable failure\n// state was reached.\ntypedef const char* wuffs_base__status;\n\n// !! INSERT wuffs_bas" +
 	"e__status names.\n\nstatic inline bool  //\nwuffs_base__status__is_complete(wuffs_base__status z) {\n  return (z == NULL) || ((*z != '$') && (*z != '#'));\n}\n\nstatic inline bool  //\nwuffs_base__status__is_error(wuffs_base__status z) {\n  return z && (*z == '#');\n}\n\nstatic inline bool  //\nwuffs_base__status__is_ok(wuffs_base__status z) {\n  return z == NULL;\n}\n\nstatic inline bool  //\nwuffs_base__status__is_suspension(wuffs_base__status z) {\n  return z && (*z == '$');\n}\n\nstatic inline bool  //\nwuffs_base__status__is_warning(wuffs_base__status z) {\n  return z && (*z != '$') && (*z != '#');\n}\n\n" +
 	"" +
+	"// --------\n\n// FourCC constants.\n\n// !! INSERT FourCCs.\n\n" +
+	"" +
 	"// --------\n\n// Flicks are a unit of time. One flick (frame-tick) is 1 / 705_600_000 of a\n// second. See https://github.com/OculusVR/Flicks\ntypedef int64_t wuffs_base__flicks;\n\n#define WUFFS_BASE__FLICKS_PER_SECOND ((uint64_t)705600000)\n#define WUFFS_BASE__FLICKS_PER_MILLISECOND ((uint64_t)705600)\n\n" +
 	"" +
 	"// ---------------- Numeric Types\n\nstatic inline uint8_t  //\nwuffs_base__u8__min(uint8_t x, uint8_t y) {\n  return x < y ? x : y;\n}\n\nstatic inline uint8_t  //\nwuffs_base__u8__max(uint8_t x, uint8_t y) {\n  return x > y ? x : y;\n}\n\nstatic inline uint16_t  //\nwuffs_base__u16__min(uint16_t x, uint16_t y) {\n  return x < y ? x : y;\n}\n\nstatic inline uint16_t  //\nwuffs_base__u16__max(uint16_t x, uint16_t y) {\n  return x > y ? x : y;\n}\n\nstatic inline uint32_t  //\nwuffs_base__u32__min(uint32_t x, uint32_t y) {\n  return x < y ? x : y;\n}\n\nstatic inline uint32_t  //\nwuffs_base__u32__max(uint32_t x, uint32_t y) {\n  return x > y ? x : y;\n}\n\nstatic inline uint64_t  //\nwuffs_base__u64__min(uint64_t x, uint64_t y) {\n  return x < y ? x : y;\n}\n\nstatic inline uint64_t  //\nwuffs_base__u64__max(uint64_t x, uint64_t y) {\n  return x > y ? x : y;\n}\n\n" +
diff --git a/lang/builtin/builtin.go b/lang/builtin/builtin.go
index 47de929..c30e2ea 100644
--- a/lang/builtin/builtin.go
+++ b/lang/builtin/builtin.go
@@ -19,6 +19,11 @@
 	t "github.com/google/wuffs/lang/token"
 )
 
+var FourCCs = [...][2]string{
+	{"ICCP", "International Color Consortium Profile"},
+	{"XMP ", "Extensible Metadata Platform"},
+}
+
 var Statuses = [...]string{
 	// Warnings.
 	`"@end of data"`,
diff --git a/release/c/wuffs-unsupported-snapshot.c b/release/c/wuffs-unsupported-snapshot.c
index fb99e91..03431b6 100644
--- a/release/c/wuffs-unsupported-snapshot.c
+++ b/release/c/wuffs-unsupported-snapshot.c
@@ -236,6 +236,16 @@
 
 // --------
 
+// FourCC constants.
+
+// International Color Consortium Profile.
+#define WUFFS_BASE__FOURCC__ICCP 0x49434350
+
+// Extensible Metadata Platform.
+#define WUFFS_BASE__FOURCC__XMP 0x584D5020
+
+// --------
+
 // Flicks are a unit of time. One flick (frame-tick) is 1 / 705_600_000 of a
 // second. See https://github.com/OculusVR/Flicks
 typedef int64_t wuffs_base__flicks;