Here is a list of all files with brief descriptions:

BitIO.h
BufferedStream.h
ChunkBuffer.h
CodeStream.h
CodingParams.h
CPUArch.h
Dump.h
dwt.h
dwt53.h
dwt97.h
dwt_utils.h
FileFormat.h
grok.h
grok_exceptions.h
grok_includes.h
grok_intmath.h
HTParams.h
IBitIO.h
IBufferedStream.h
image.h	Implementation of operations on images (IMAGE)
invert.h	Implementation of the matrix inversion
LengthMarkers.h
logger.h
markers.h
mct.h	Implementation of a multi-component transforms (MCT)
mem_stream.h
MemManager.h
minpf_common.h
minpf_dynamic_library.h
minpf_plugin.h
minpf_plugin_manager.h
mqc.h
mqc_dec_inl.h
mqc_enc_inl.h
mqc_inl.h
ojph_arch.h
ojph_arg.h
ojph_base.h
ojph_block_decoder.h
ojph_block_encoder.h
ojph_defs.h
ojph_mem.h
ojph_message.h
PacketIter.h	Implementation of a packet iterator (PI)
plugin_bridge.h
plugin_interface.h
PPMMarker.h
Profile.h
Quantizer.h
RateControl.h
RateInfo.h
simd.h
SIZMarker.h
SOTMarker.h
sparse_array.h	Sparse array management
t1.h
t1_common.h
t1_flags.h
t1_luts.h
T1Decoder.h
T1Encoder.h
T1Factory.h
T1HT.h
T1Interface.h
T1Part1.h
T2.h	Implementation of a tier-2 coding (packetization of code-block data) (T2)
T2Decode.h
T2Encode.h
table0.h
table1.h
TagTree.h
testing.h
Tier1.h
TileComponent.h
TileComponentBuffer.h
TileProcessor.h
util.h
Wavelet.h
WaveletForward.h