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diff --git a/third_party/jpeg-xl/lib/extras/dec/color_hints.h b/third_party/jpeg-xl/lib/extras/dec/color_hints.h
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+++ b/third_party/jpeg-xl/lib/extras/dec/color_hints.h
@@ -0,0 +1,72 @@
+// Copyright (c) the JPEG XL Project Authors. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#ifndef LIB_EXTRAS_COLOR_HINTS_H_
+#define LIB_EXTRAS_COLOR_HINTS_H_
+
+// Not all the formats implemented in the extras lib support bundling color
+// information into the file, and those that support it may not have it.
+// To allow attaching color information to those file formats the caller can
+// define these color hints.
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <string>
+#include <vector>
+
+#include "lib/extras/packed_image.h"
+#include "lib/jxl/base/status.h"
+
+namespace jxl {
+namespace extras {
+
+class ColorHints {
+ public:
+  // key=color_space, value=Description(c/pp): specify the ColorEncoding of
+  //   the pixels for decoding. Otherwise, if the codec did not obtain an ICC
+  //   profile from the image, assume sRGB.
+  //
+  // Strings are taken from the command line, so avoid spaces for convenience.
+  void Add(const std::string& key, const std::string& value) {
+    kv_.emplace_back(key, value);
+  }
+
+  // Calls `func(key, value)` for each key/value in the order they were added,
+  // returning false immediately if `func` returns false.
+  template <class Func>
+  Status Foreach(const Func& func) const {
+    for (const KeyValue& kv : kv_) {
+      Status ok = func(kv.key, kv.value);
+      if (!ok) {
+        return JXL_FAILURE("ColorHints::Foreach returned false");
+      }
+    }
+    return true;
+  }
+
+ private:
+  // Splitting into key/value avoids parsing in each codec.
+  struct KeyValue {
+    KeyValue(std::string key, std::string value)
+        : key(std::move(key)), value(std::move(value)) {}
+
+    std::string key;
+    std::string value;
+  };
+
+  std::vector<KeyValue> kv_;
+};
+
+// Apply the color hints to the decoded image in PackedPixelFile if any.
+// color_already_set tells whether the color encoding was already set, in which
+// case the hints are ignored if any hint is passed.
+Status ApplyColorHints(const ColorHints& color_hints, bool color_already_set,
+                       bool is_gray, PackedPixelFile* ppf);
+
+}  // namespace extras
+}  // namespace jxl
+
+#endif  // LIB_EXTRAS_COLOR_HINTS_H_