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+This is a library of compression algorithms with a unified interface and serialization.
+See also library/cpp/codecs/static, where a support for statically compiled dictionaries is implemented.
+
+All algorithms have a common `ICodec` interface (described in codecs.h).
+
+The `ICodec` interface has the following methods:\
+    `virtual ui8 ICodec::Encode (TMemoryRegion, TBuffer&) const;`\
+            - Input - memory region. Output - filled buffer and the rest of the last byte, if it was not filled to the end.\
+    `virtual void ICodec::Decode (TMemoryRegion, TBuffer&) const;`\
+            - Input - memory region. Output - filled buffer.\
+    `virtual void Save (TOutputStream*) const;`\
+            - Serialization.\
+    `virtual void Load (TInputStream*);`\
+            - Deserialization.\
+    `virtual bool NeedsTraining() const;`\
+            - Returns if it is necessary or not to teach this codec.\
+    `virtual bool PaddingBit() const;`\
+            - Returns which values should fill the free bits of the last byte.\
+    `virtual size_t ApproximateSizeOnEncode(size_t sz) const;`\
+            - Returns an approximate estimate of the size of the result after encoding.\
+                    For example could be used for a more accurate preallocation of a buffer.\
+    `virtual size_t ApproximateSizeOnDecode(size_t sz) const;`\
+            - Returns an approximate estimate of the size of the result after decoding.\
+                    For example could be used for a more accurate preallocation of a buffer.\
+    `virtual TString GetName() const;`\
+            - The name of the codec. It is required for registration of the codec in the system of serialization/deserialization.\
+                    For example, it allows you to save information about which combination of codecs was in use (see below).\
+    `virtual void Learn(ISequenceReader*);`\
+            - The interface for teaching codecs that use information about the distribution of data.
+
+In addition, the library has a number of utilities that allow a more flexible use of it.
+
+In the `ICodec` class the following methods are available:\
+    `static TCodecPtr GetInstance(const TString& name);`\
+            - Creation of a codec instance by a symbolic name\
+                    (See `GetName()` above)\
+    `static void Store(TOutputStream*, TCodecPtr p);`\
+            - Serialization of the codec along with its name\
+                    Allows you to save information about which particular combination of codecs was used for encoding,\
+                    and then reassemble the same combination for decoding\
+    `static TCodecPtr Restore(TInputStream* in);`\
+            - Serialization of the codec along with its name\
+    `static TCodecPtr RestoreFromString(TStringBuf data);`\
+            - Loads the codec instance from the string\
+    `static TVector<TString> GetCodecsList();`\
+            - The list of registered codecs