1 files changed, 45 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/enc_toc.cc b/third_party/jpeg-xl/lib/jxl/enc_toc.cc
new file mode 100644
index 0000000000..dc75fdd9ba
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/enc_toc.cc
@@ -0,0 +1,45 @@
+// 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_toc.h"
+
+#include <stdint.h>
+
+#include "lib/jxl/coeff_order.h"
+#include "lib/jxl/common.h"
+#include "lib/jxl/enc_aux_out.h"
+#include "lib/jxl/enc_coeff_order.h"
+#include "lib/jxl/field_encodings.h"
+#include "lib/jxl/fields.h"
+#include "lib/jxl/toc.h"
+
+namespace jxl {
+Status WriteGroupOffsets(const std::vector<BitWriter>& group_codes,
+                         const std::vector<coeff_order_t>* permutation,
+                         BitWriter* JXL_RESTRICT writer, AuxOut* aux_out) {
+  BitWriter::Allotment allotment(writer, MaxBits(group_codes.size()));
+  if (permutation && !group_codes.empty()) {
+    // Don't write a permutation at all for an empty group_codes.
+    writer->Write(1, 1);  // permutation
+    JXL_DASSERT(permutation->size() == group_codes.size());
+    EncodePermutation(permutation->data(), /*skip=*/0, permutation->size(),
+                      writer, /* layer= */ 0, aux_out);
+
+  } else {
+    writer->Write(1, 0);  // no permutation
+  }
+  writer->ZeroPadToByte();  // before TOC entries
+
+  for (size_t i = 0; i < group_codes.size(); i++) {
+    JXL_ASSERT(group_codes[i].BitsWritten() % kBitsPerByte == 0);
+    const size_t group_size = group_codes[i].BitsWritten() / kBitsPerByte;
+    JXL_RETURN_IF_ERROR(U32Coder::Write(kTocDist, group_size, writer));
+  }
+  writer->ZeroPadToByte();  // before first group
+  allotment.ReclaimAndCharge(writer, kLayerTOC, aux_out);
+  return true;
+}
+
+}  // namespace jxl