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diff --git a/zopfli/blocksplitter.h b/zopfli/blocksplitter.h
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+/*
+Copyright 2011 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Author: lode.vandevenne@gmail.com (Lode Vandevenne)
+Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala)
+*/
+
+/*
+Functions to choose good boundaries for block splitting. Deflate allows encoding
+the data in multiple blocks, with a separate Huffman tree for each block. The
+Huffman tree itself requires some bytes to encode, so by choosing certain
+blocks, you can either hurt, or enhance compression. These functions choose good
+ones that enhance it.
+*/
+
+#ifndef ZOPFLI_BLOCKSPLITTER_H_
+#define ZOPFLI_BLOCKSPLITTER_H_
+
+#include <stdlib.h>
+
+#include "zopfli.h"
+
+
+/*
+Does blocksplitting on LZ77 data.
+The output splitpoints are indices in the LZ77 data.
+litlens: lz77 lit/lengths
+dists: lz77 distances
+llsize: size of litlens and dists
+maxblocks: set a limit to the amount of blocks. Set to 0 to mean no limit.
+*/
+void ZopfliBlockSplitLZ77(const ZopfliOptions* options,
+                          const unsigned short* litlens,
+                          const unsigned short* dists,
+                          size_t llsize, size_t maxblocks,
+                          size_t** splitpoints, size_t* npoints);
+
+/*
+Does blocksplitting on uncompressed data.
+The output splitpoints are indices in the uncompressed bytes.
+
+options: general program options.
+in: uncompressed input data
+instart: where to start splitting
+inend: where to end splitting (not inclusive)
+maxblocks: maximum amount of blocks to split into, or 0 for no limit
+splitpoints: dynamic array to put the resulting split point coordinates into.
+  The coordinates are indices in the input array.
+npoints: pointer to amount of splitpoints, for the dynamic array. The amount of
+  blocks is the amount of splitpoitns + 1.
+*/
+void ZopfliBlockSplit(const ZopfliOptions* options,
+                      const unsigned char* in, size_t instart, size_t inend,
+                      size_t maxblocks, size_t** splitpoints, size_t* npoints);
+
+/*
+Divides the input into equal blocks, does not even take LZ77 lengths into
+account.
+*/
+void ZopfliBlockSplitSimple(const unsigned char* in,
+                            size_t instart, size_t inend,
+                            size_t blocksize,
+                            size_t** splitpoints, size_t* npoints);
+
+#endif  /* ZOPFLI_BLOCKSPLITTER_H_ */