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diff --git a/third_party/jpeg-xl/lib/jxl/enc_ans_params.h b/third_party/jpeg-xl/lib/jxl/enc_ans_params.h
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+++ b/third_party/jpeg-xl/lib/jxl/enc_ans_params.h
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+// 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_JXL_ENC_ANS_PARAMS_H_
+#define LIB_JXL_ENC_ANS_PARAMS_H_
+
+// Encoder-only parameter needed for ANS entropy encoding methods.
+
+#include <stdint.h>
+#include <stdlib.h>
+
+#include "lib/jxl/enc_params.h"
+
+namespace jxl {
+
+struct HistogramParams {
+  enum class ClusteringType {
+    kFastest,  // Only 4 clusters.
+    kFast,
+    kBest,
+  };
+
+  enum class HybridUintMethod {
+    kNone,        // just use kHybridUint420Config.
+    k000,         // force the fastest option.
+    kFast,        // just try a couple of options.
+    kContextMap,  // fast choice for ctx map.
+    kBest,
+  };
+
+  enum class LZ77Method {
+    kNone,     // do not try lz77.
+    kRLE,      // only try doing RLE.
+    kLZ77,     // try lz77 with backward references.
+    kOptimal,  // optimal-matching LZ77 parsing.
+  };
+
+  enum class ANSHistogramStrategy {
+    kFast,         // Only try some methods, early exit.
+    kApproximate,  // Only try some methods.
+    kPrecise,      // Try all methods.
+  };
+
+  HistogramParams() = default;
+
+  HistogramParams(SpeedTier tier, size_t num_ctx) {
+    if (tier > SpeedTier::kFalcon) {
+      clustering = ClusteringType::kFastest;
+      lz77_method = LZ77Method::kNone;
+    } else if (tier > SpeedTier::kTortoise) {
+      clustering = ClusteringType::kFast;
+    } else {
+      clustering = ClusteringType::kBest;
+    }
+    if (tier > SpeedTier::kTortoise) {
+      uint_method = HybridUintMethod::kNone;
+    }
+    if (tier >= SpeedTier::kSquirrel) {
+      ans_histogram_strategy = ANSHistogramStrategy::kApproximate;
+    }
+  }
+
+  ClusteringType clustering = ClusteringType::kBest;
+  HybridUintMethod uint_method = HybridUintMethod::kBest;
+  LZ77Method lz77_method = LZ77Method::kRLE;
+  ANSHistogramStrategy ans_histogram_strategy = ANSHistogramStrategy::kPrecise;
+  std::vector<size_t> image_widths;
+  size_t max_histograms = ~0;
+  bool force_huffman = false;
+};
+
+}  // namespace jxl
+
+#endif  // LIB_JXL_ENC_ANS_PARAMS_H_