1 files changed, 35 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/enc_context_map.h b/third_party/jpeg-xl/lib/jxl/enc_context_map.h
new file mode 100644
index 0000000000..041e71de7a
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/enc_context_map.h
@@ -0,0 +1,35 @@
+// 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_CONTEXT_MAP_H_
+#define LIB_JXL_ENC_CONTEXT_MAP_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <vector>
+
+#include "lib/jxl/ac_context.h"
+#include "lib/jxl/enc_bit_writer.h"
+
+namespace jxl {
+
+struct AuxOut;
+
+// Max limit is 255 because encoding assumes numbers < 255
+// More clusters can help compression, but makes encode/decode somewhat slower
+static const size_t kClustersLimit = 128;
+
+// Encodes the given context map to the bit stream. The number of different
+// histogram ids is given by num_histograms.
+void EncodeContextMap(const std::vector<uint8_t>& context_map,
+                      size_t num_histograms, BitWriter* writer, size_t layer,
+                      AuxOut* aux_out);
+
+void EncodeBlockCtxMap(const BlockCtxMap& block_ctx_map, BitWriter* writer,
+                       AuxOut* aux_out);
+}  // namespace jxl
+
+#endif  // LIB_JXL_ENC_CONTEXT_MAP_H_