1 files changed, 141 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/modular/transform/enc_squeeze.cc b/third_party/jpeg-xl/lib/jxl/modular/transform/enc_squeeze.cc
new file mode 100644
index 0000000000..dfd90cde68
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/modular/transform/enc_squeeze.cc
@@ -0,0 +1,141 @@
+// 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/modular/transform/enc_squeeze.h"
+
+#include <stdlib.h>
+
+#include "lib/jxl/base/data_parallel.h"
+#include "lib/jxl/common.h"
+#include "lib/jxl/modular/modular_image.h"
+#include "lib/jxl/modular/transform/squeeze.h"
+#include "lib/jxl/modular/transform/transform.h"
+
+namespace jxl {
+
+void FwdHSqueeze(Image &input, int c, int rc) {
+  const Channel &chin = input.channel[c];
+
+  JXL_DEBUG_V(4, "Doing horizontal squeeze of channel %i to new channel %i", c,
+              rc);
+
+  Channel chout((chin.w + 1) / 2, chin.h, chin.hshift + 1, chin.vshift);
+  Channel chout_residual(chin.w - chout.w, chout.h, chin.hshift + 1,
+                         chin.vshift);
+
+  for (size_t y = 0; y < chout.h; y++) {
+    const pixel_type *JXL_RESTRICT p_in = chin.Row(y);
+    pixel_type *JXL_RESTRICT p_out = chout.Row(y);
+    pixel_type *JXL_RESTRICT p_res = chout_residual.Row(y);
+    for (size_t x = 0; x < chout_residual.w; x++) {
+      pixel_type A = p_in[x * 2];
+      pixel_type B = p_in[x * 2 + 1];
+      pixel_type avg = (A + B + (A > B)) >> 1;
+      p_out[x] = avg;
+
+      pixel_type diff = A - B;
+
+      pixel_type next_avg = avg;
+      if (x + 1 < chout_residual.w) {
+        next_avg = (p_in[x * 2 + 2] + p_in[x * 2 + 3] +
+                    (p_in[x * 2 + 2] > p_in[x * 2 + 3])) >>
+                   1;  // which will be chout.value(y,x+1)
+      } else if (chin.w & 1)
+        next_avg = p_in[x * 2 + 2];
+      pixel_type left = (x > 0 ? p_in[x * 2 - 1] : avg);
+      pixel_type tendency = SmoothTendency(left, avg, next_avg);
+
+      p_res[x] = diff - tendency;
+    }
+    if (chin.w & 1) {
+      int x = chout.w - 1;
+      p_out[x] = p_in[x * 2];
+    }
+  }
+  input.channel[c] = std::move(chout);
+  input.channel.insert(input.channel.begin() + rc, std::move(chout_residual));
+}
+
+void FwdVSqueeze(Image &input, int c, int rc) {
+  const Channel &chin = input.channel[c];
+
+  JXL_DEBUG_V(4, "Doing vertical squeeze of channel %i to new channel %i", c,
+              rc);
+
+  Channel chout(chin.w, (chin.h + 1) / 2, chin.hshift, chin.vshift + 1);
+  Channel chout_residual(chin.w, chin.h - chout.h, chin.hshift,
+                         chin.vshift + 1);
+  intptr_t onerow_in = chin.plane.PixelsPerRow();
+  for (size_t y = 0; y < chout_residual.h; y++) {
+    const pixel_type *JXL_RESTRICT p_in = chin.Row(y * 2);
+    pixel_type *JXL_RESTRICT p_out = chout.Row(y);
+    pixel_type *JXL_RESTRICT p_res = chout_residual.Row(y);
+    for (size_t x = 0; x < chout.w; x++) {
+      pixel_type A = p_in[x];
+      pixel_type B = p_in[x + onerow_in];
+      pixel_type avg = (A + B + (A > B)) >> 1;
+      p_out[x] = avg;
+
+      pixel_type diff = A - B;
+
+      pixel_type next_avg = avg;
+      if (y + 1 < chout_residual.h) {
+        next_avg = (p_in[x + 2 * onerow_in] + p_in[x + 3 * onerow_in] +
+                    (p_in[x + 2 * onerow_in] > p_in[x + 3 * onerow_in])) >>
+                   1;  // which will be chout.value(y+1,x)
+      } else if (chin.h & 1) {
+        next_avg = p_in[x + 2 * onerow_in];
+      }
+      pixel_type top =
+          (y > 0 ? p_in[static_cast<ssize_t>(x) - onerow_in] : avg);
+      pixel_type tendency = SmoothTendency(top, avg, next_avg);
+
+      p_res[x] = diff - tendency;
+    }
+  }
+  if (chin.h & 1) {
+    size_t y = chout.h - 1;
+    const pixel_type *p_in = chin.Row(y * 2);
+    pixel_type *p_out = chout.Row(y);
+    for (size_t x = 0; x < chout.w; x++) {
+      p_out[x] = p_in[x];
+    }
+  }
+  input.channel[c] = std::move(chout);
+  input.channel.insert(input.channel.begin() + rc, std::move(chout_residual));
+}
+
+Status FwdSqueeze(Image &input, std::vector<SqueezeParams> parameters,
+                  ThreadPool *pool) {
+  if (parameters.empty()) {
+    DefaultSqueezeParameters(&parameters, input);
+  }
+  // if nothing to do, don't do squeeze
+  if (parameters.empty()) return false;
+  for (size_t i = 0; i < parameters.size(); i++) {
+    JXL_RETURN_IF_ERROR(
+        CheckMetaSqueezeParams(parameters[i], input.channel.size()));
+    bool horizontal = parameters[i].horizontal;
+    bool in_place = parameters[i].in_place;
+    uint32_t beginc = parameters[i].begin_c;
+    uint32_t endc = parameters[i].begin_c + parameters[i].num_c - 1;
+    uint32_t offset;
+    if (in_place) {
+      offset = endc + 1;
+    } else {
+      offset = input.channel.size();
+    }
+    for (uint32_t c = beginc; c <= endc; c++) {
+      if (horizontal) {
+        FwdHSqueeze(input, c, offset + c - beginc);
+      } else {
+        FwdVSqueeze(input, c, offset + c - beginc);
+      }
+    }
+  }
+  return true;
+}
+
+}  // namespace jxl