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diff --git a/third_party/jpeg-xl/lib/jxl/enc_gaborish.cc b/third_party/jpeg-xl/lib/jxl/enc_gaborish.cc
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+++ b/third_party/jpeg-xl/lib/jxl/enc_gaborish.cc
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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.
+
+#include "lib/jxl/enc_gaborish.h"
+
+#include <stddef.h>
+
+#include <hwy/base.h>
+
+#include "lib/jxl/base/status.h"
+#include "lib/jxl/convolve.h"
+#include "lib/jxl/image_ops.h"
+
+namespace jxl {
+
+void GaborishInverse(Image3F* in_out, float mul[3], ThreadPool* pool) {
+  WeightsSymmetric5 weights[3];
+  // Only an approximation. One or even two 3x3, and rank-1 (separable) 5x5
+  // are insufficient. The numbers here have been obtained by butteraugli
+  // based optimizing the whole system and the errors produced are likely
+  // more favorable for good rate-distortion compromises rather than
+  // just using mathematical optimization to find the inverse.
+  static const float kGaborish[5] = {
+      -0.090881924078487886f, -0.043663953593472138f, 0.01392497846646211f,
+      0.0036189602184591141f, 0.0030557936884763499f};
+  for (int i = 0; i < 3; ++i) {
+    double sum = 1.0 + mul[i] * 4 *
+                           (kGaborish[0] + kGaborish[1] + kGaborish[2] +
+                            kGaborish[4] + 2 * kGaborish[3]);
+    if (sum < 1e-5) {
+      sum = 1e-5;
+    }
+    const float normalize = static_cast<float>(1.0 / sum);
+    const float normalize_mul = mul[i] * normalize;
+    weights[i] = WeightsSymmetric5{{HWY_REP4(normalize)},
+                                   {HWY_REP4(normalize_mul * kGaborish[0])},
+                                   {HWY_REP4(normalize_mul * kGaborish[2])},
+                                   {HWY_REP4(normalize_mul * kGaborish[1])},
+                                   {HWY_REP4(normalize_mul * kGaborish[4])},
+                                   {HWY_REP4(normalize_mul * kGaborish[3])}};
+  }
+  // Reduce memory footprint by only allocating a single plane and swapping it
+  // into the output Image3F. Better still would be tiling.
+  // Note that we cannot *allocate* a plane, as doing so might cause Image3F to
+  // have planes of different stride. Instead, we copy one plane in a temporary
+  // image and reuse the existing planes of the in/out image.
+  ImageF temp = CopyImage(in_out->Plane(2));
+  Symmetric5(in_out->Plane(0), Rect(*in_out), weights[0], pool,
+             &in_out->Plane(2));
+  Symmetric5(in_out->Plane(1), Rect(*in_out), weights[1], pool,
+             &in_out->Plane(0));
+  Symmetric5(temp, Rect(*in_out), weights[2], pool, &in_out->Plane(1));
+  // Now planes are 1, 2, 0.
+  in_out->Plane(0).Swap(in_out->Plane(1));
+  // 2 1 0
+  in_out->Plane(0).Swap(in_out->Plane(2));
+}
+
+}  // namespace jxl