public int laszip_open_writer(string file_name, bool compress)
{
if(file_name==null||file_name.Length==0)
{
error="string file_name pointer is zero";
return 1;
}
if(reader!=null)
{
error="reader is already open";
return 1;
}
if(writer!=null)
{
error="writer is already open";
return 1;
}
try
{
#region check header and prepare point
uint vlrs_size=0;
if(header.version_major!=1)
{
error=string.Format("unknown LAS version {0}.{1}", header.version_major, header.version_minor);
return 1;
}
if(compress&&(header.point_data_format>5))
{
error=string.Format("compressor does not yet support point data format {1}", header.point_data_format);
return 1;
}
if(header.number_of_variable_length_records!=0)
{
if(header.vlrs==null)
{
error=string.Format("number_of_variable_length_records is {0} but vlrs pointer is zero", header.number_of_variable_length_records);
return 1;
}
for(int i=0; i<header.number_of_variable_length_records; i++)
{
vlrs_size+=54;
if(header.vlrs[i].record_length_after_header!=0)
{
if(header.vlrs==null)
{
error=string.Format("vlrs[{0}].record_length_after_header is {1} but vlrs[{0}].data pointer is zero", i, header.vlrs[i].record_length_after_header);
return 1;
}
vlrs_size+=header.vlrs[i].record_length_after_header;
}
}
}
if((vlrs_size+header.header_size+header.user_data_after_header_size)!=header.offset_to_point_data)
{
error=string.Format("header_size ({0}) plus vlrs_size ({1}) plus user_data_after_header_size ({2}) does not equal offset_to_point_data ({3})", header.header_size, vlrs_size, header.user_data_after_header_size, header.offset_to_point_data);
return 1;
}
LASzip laszip=null;
try
{
laszip=new LASzip();
}
catch
{
error="could not alloc LASzip";
return 1;
}
if(!laszip.setup(header.point_data_format, header.point_data_record_length, LASzip.COMPRESSOR_NONE))
{
error=string.Format("invalid combination of point_data_format {0} and point_data_record_length {1}", header.point_data_format, header.point_data_record_length);
return 1;
}
#region create point's item pointers
for(uint i=0; i<laszip.num_items; i++)
{
switch(laszip.items[i].type)
{
case LASitem.Type.POINT14:
case LASitem.Type.POINT10:
case LASitem.Type.GPSTIME11:
case LASitem.Type.RGBNIR14:
case LASitem.Type.RGB12:
case LASitem.Type.WAVEPACKET13: break;
case LASitem.Type.BYTE:
point.num_extra_bytes=laszip.items[i].size;
point.extra_bytes=new byte[point.num_extra_bytes];
break;
default:
error=string.Format("unknown LASitem type {0}", laszip.items[i].type);
return 1;
}
}
#endregion
uint laszip_vrl_payload_size=0;
if(compress)
{
if(!laszip.setup(header.point_data_format, header.point_data_record_length, LASzip.COMPRESSOR_DEFAULT))
{
error=string.Format("cannot compress point_data_format {0} with point_data_record_length {1}", header.point_data_format, header.point_data_record_length);
return 1;
}
laszip.request_version(2);
laszip_vrl_payload_size=34u+6u*laszip.num_items;
}
else
{
laszip.request_version(0);
}
#endregion
#region open the file
try
{
streamout=new FileStream(file_name, FileMode.Create, FileAccess.Write, FileShare.Read);
}
catch
{
error=string.Format("cannot open file '{0}'", file_name);
return 1;
}
#endregion
#region write the header variable after variable
try
{
streamout.WriteByte((byte)'L');
streamout.WriteByte((byte)'A');
streamout.WriteByte((byte)'S');
streamout.WriteByte((byte)'F');
}
catch
{
error="writing header.file_signature";
return 1;
}
try { streamout.Write(BitConverter.GetBytes(header.file_source_ID), 0, 2); }
catch { error="writing header.file_source_ID"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.global_encoding), 0, 2); }
catch { error="writing header.global_encoding"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.project_ID_GUID_data_1), 0, 4); }
catch { error="writing header.project_ID_GUID_data_1"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.project_ID_GUID_data_2), 0, 2); }
catch { error="writing header.project_ID_GUID_data_2"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.project_ID_GUID_data_3), 0, 2); }
catch { error="writing header.project_ID_GUID_data_3"; return 1; }
try { streamout.Write(header.project_ID_GUID_data_4, 0, 8); }
catch { error="writing header.project_ID_GUID_data_4"; return 1; }
try { streamout.WriteByte(header.version_major); }
catch { error="writing header.version_major"; return 1; }
try { streamout.WriteByte(header.version_minor); }
catch { error="writing header.version_minor"; return 1; }
try { streamout.Write(header.system_identifier, 0, 32); }
catch { error="writing header.system_identifier"; return 1; }
byte[] generatingSoftware=Encoding.ASCII.GetBytes(string.Format("LASzip DLL {0}.{1} r{2} ({3})", LASzip.VERSION_MAJOR, LASzip.VERSION_MINOR, LASzip.VERSION_REVISION, LASzip.VERSION_BUILD_DATE));
Array.Copy(generatingSoftware, header.generating_software, Math.Min(generatingSoftware.Length, 32));
try { streamout.Write(header.generating_software, 0, 32); }
catch { error="writing header.generating_software"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.file_creation_day), 0, 2); }
catch { error="writing header.file_creation_day"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.file_creation_year), 0, 2); }
catch { error="writing header.file_creation_year"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.header_size), 0, 2); }
catch { error="writing header.header_size"; return 1; }
if(compress) header.offset_to_point_data+=(54+laszip_vrl_payload_size);
try { streamout.Write(BitConverter.GetBytes(header.offset_to_point_data), 0, 4); }
catch { error="writing header.offset_to_point_data"; return 1; }
if(compress)
{
header.offset_to_point_data-=(54+laszip_vrl_payload_size);
header.number_of_variable_length_records+=1;
}
try { streamout.Write(BitConverter.GetBytes(header.number_of_variable_length_records), 0, 4); }
catch { error="writing header.number_of_variable_length_records"; return 1; }
if(compress)
{
header.number_of_variable_length_records-=1;
header.point_data_format|=128;
}
try { streamout.WriteByte(header.point_data_format); }
catch { error="writing header.point_data_format"; return 1; }
if(compress) header.point_data_format&=127;
try { streamout.Write(BitConverter.GetBytes(header.point_data_record_length), 0, 2); }
catch { error="writing header.point_data_record_length"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.number_of_point_records), 0, 4); }
catch { error="writing header.number_of_point_records"; return 1; }
for(uint i=0; i<5; i++)
{
try { streamout.Write(BitConverter.GetBytes(header.number_of_points_by_return[i]), 0, 4); }
catch { error=string.Format("writing header.number_of_points_by_return {0}", i); return 1; }
}
try { streamout.Write(BitConverter.GetBytes(header.x_scale_factor), 0, 8); }
catch { error="writing header.x_scale_factor"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.y_scale_factor), 0, 8); }
catch { error="writing header.y_scale_factor"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.z_scale_factor), 0, 8); }
catch { error="writing header.z_scale_factor"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.x_offset), 0, 8); }
catch { error="writing header.x_offset"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.y_offset), 0, 8); }
catch { error="writing header.y_offset"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.z_offset), 0, 8); }
catch { error="writing header.z_offset"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.max_x), 0, 8); }
catch { error="writing header.max_x"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.min_x), 0, 8); }
catch { error="writing header.min_x"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.max_y), 0, 8); }
catch { error="writing header.max_y"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.min_y), 0, 8); }
catch { error="writing header.min_y"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.max_z), 0, 8); }
catch { error="writing header.max_z"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.min_z), 0, 8); }
catch { error="writing header.min_z"; return 1; }
#region special handling for LAS 1.3+
if(header.version_major==1&&header.version_minor>=3)
{
if(header.header_size<235)
{
error=string.Format("for LAS 1.{0} header_size should at least be 235 but it is only {1}", header.version_minor, header.header_size);
return 1;
}
try { streamout.Write(BitConverter.GetBytes(header.start_of_waveform_data_packet_record), 0, 8); }
catch { error="writing header.start_of_waveform_data_packet_record"; return 1; }
header.user_data_in_header_size=header.header_size-235u;
}
else header.user_data_in_header_size=header.header_size-227u;
#endregion
#region special handling for LAS 1.4+
if(header.version_major==1&&header.version_minor>=4)
{
if(header.header_size<375)
{
error=string.Format("for LAS 1.{0} header_size should at least be 375 but it is only {1}", header.version_minor, header.header_size);
return 1;
}
try { streamout.Write(BitConverter.GetBytes(header.start_of_first_extended_variable_length_record), 0, 8); }
catch { error="writing header.start_of_first_extended_variable_length_record"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.number_of_extended_variable_length_records), 0, 4); }
catch { error="writing header.number_of_extended_variable_length_records"; return 1; }
try { streamout.Write(BitConverter.GetBytes(header.extended_number_of_point_records), 0, 8); }
catch { error="writing header.extended_number_of_point_records"; return 1; }
for(uint i=0; i<15; i++)
{
try { streamout.Write(BitConverter.GetBytes(header.extended_number_of_points_by_return[i]), 0, 8); }
catch { error=string.Format("writing header.extended_number_of_points_by_return[{0}]", i); return 1; }
}
header.user_data_in_header_size=header.header_size-375u;
}
#endregion
#region write any number of user-defined bytes that might have been added to the header
if(header.user_data_in_header_size!=0)
{
try { streamout.Write(header.user_data_in_header, 0, (int)header.user_data_in_header_size); }
catch { error=string.Format("writing {0} bytes of data into header.user_data_in_header", header.user_data_in_header_size); return 1; }
}
#endregion
#region write variable length records into the header
if(header.number_of_variable_length_records!=0)
{
for(int i=0; i<header.number_of_variable_length_records; i++)
{
// write variable length records variable after variable (to avoid alignment issues)
try { streamout.Write(BitConverter.GetBytes(header.vlrs[i].reserved), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].reserved", i); return 1; }
try { streamout.Write(header.vlrs[i].user_id, 0, 16); }
catch { error=string.Format("writing header.vlrs[{0}].user_id", i); return 1; }
try { streamout.Write(BitConverter.GetBytes(header.vlrs[i].record_id), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].record_id", i); return 1; }
try { streamout.Write(BitConverter.GetBytes(header.vlrs[i].record_length_after_header), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].record_length_after_header", i); return 1; }
try { streamout.Write(header.vlrs[i].description, 0, 32); }
catch { error=string.Format("writing header.vlrs[{0}].description", i); return 1; }
// write data following the header of the variable length record
if(header.vlrs[i].record_length_after_header!=0)
{
try { streamout.Write(header.vlrs[i].data, 0, header.vlrs[i].record_length_after_header); }
catch { error=string.Format("writing {0} bytes of data into header.vlrs[{1}].data", header.vlrs[i].record_length_after_header, i); return 1; }
}
}
}
if(compress)
{
#region write the LASzip VLR header
uint i=header.number_of_variable_length_records;
ushort reserved=0xAABB;
try { streamout.Write(BitConverter.GetBytes(reserved), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].reserved", i); return 1; }
byte[] user_id1=Encoding.ASCII.GetBytes("laszip encoded");
byte[] user_id=new byte[16];
Array.Copy(user_id1, user_id, Math.Min(16, user_id1.Length));
try { streamout.Write(user_id, 0, 16); }
catch { error=string.Format("writing header.vlrs[{0}].user_id", i); return 1; }
ushort record_id=22204;
try { streamout.Write(BitConverter.GetBytes(record_id), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].record_id", i); return 1; }
ushort record_length_after_header=(ushort)laszip_vrl_payload_size;
try { streamout.Write(BitConverter.GetBytes(record_length_after_header), 0, 2); }
catch { error=string.Format("writing header.vlrs[{0}].record_length_after_header", i); return 1; }
byte[] description1=Encoding.ASCII.GetBytes(string.Format("LASzip DLL {0}.{1} r{2} ({3})", LASzip.VERSION_MAJOR, LASzip.VERSION_MINOR, LASzip.VERSION_REVISION, LASzip.VERSION_BUILD_DATE));
byte[] description=new byte[32];
try { streamout.Write(description, 0, 32); }
catch { error=string.Format("writing header.vlrs[{0}].description", i); return 1; }
// write the LASzip VLR payload
// U16 compressor 2 bytes
// U32 coder 2 bytes
// U8 version_major 1 byte
// U8 version_minor 1 byte
// U16 version_revision 2 bytes
// U32 options 4 bytes
// I32 chunk_size 4 bytes
// I64 number_of_special_evlrs 8 bytes
// I64 offset_to_special_evlrs 8 bytes
// U16 num_items 2 bytes
// U16 type 2 bytes * num_items
// U16 size 2 bytes * num_items
// U16 version 2 bytes * num_items
// which totals 34+6*num_items
try { streamout.Write(BitConverter.GetBytes(laszip.compressor), 0, 2); }
catch { error=string.Format("writing compressor {0}", laszip.compressor); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.coder), 0, 2); }
catch { error=string.Format("writing coder {0}", laszip.coder); return 1; }
try { streamout.WriteByte(laszip.version_major); }
catch { error=string.Format("writing version_major {0}", laszip.version_major); return 1; }
try { streamout.WriteByte(laszip.version_minor); }
catch { error=string.Format("writing version_minor {0}", laszip.version_minor); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.version_revision), 0, 2); }
catch { error=string.Format("writing version_revision {0}", laszip.version_revision); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.options), 0, 4); }
catch { error=string.Format("writing options {0}", laszip.options); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.chunk_size), 0, 4); }
catch { error=string.Format("writing chunk_size {0}", laszip.chunk_size); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.number_of_special_evlrs), 0, 8); }
catch { error=string.Format("writing number_of_special_evlrs {0}", laszip.number_of_special_evlrs); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.offset_to_special_evlrs), 0, 8); }
catch { error=string.Format("writing offset_to_special_evlrs {0}", laszip.offset_to_special_evlrs); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.num_items), 0, 2); }
catch { error=string.Format("writing num_items {0}", laszip.num_items); return 1; }
for(uint j=0; j<laszip.num_items; j++)
{
ushort type=(ushort)laszip.items[j].type;
try { streamout.Write(BitConverter.GetBytes(type), 0, 2); }
catch { error=string.Format("writing type {0} of item {1}", laszip.items[j].type, j); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.items[j].size), 0, 2); }
catch { error=string.Format("writing size {0} of item {1}", laszip.items[j].size, j); return 1; }
try { streamout.Write(BitConverter.GetBytes(laszip.items[j].version), 0, 2); }
catch { error=string.Format("writing version {0} of item {1}", laszip.items[j].version, j); return 1; }
}
#endregion
}
#endregion
#region write any number of user-defined bytes that might have been added after the header
if(header.user_data_after_header_size!=0)
{
try { streamout.Write(header.user_data_after_header, 0, (int)header.user_data_after_header_size); }
catch { error=string.Format("writing {0} bytes of data into header.user_data_after_header", header.user_data_after_header_size); return 1; }
}
#endregion
#endregion
#region create the point writer
try { writer=new LASwritePoint(); }
catch { error="could not alloc LASwritePoint"; return 1; }
if(!writer.setup(laszip.num_items, laszip.items, laszip))
{
error="setup of LASwritePoint failed";
return 1;
}
if(!writer.init(streamout))
{
error="init of LASwritePoint failed";
return 1;
}
#endregion
// set the point number and point count
npoints=header.number_of_point_records;
p_count=0;
}
catch
{
error=string.Format("internal error in laszip_open_writer '{0}'", file_name);
return 1;
}
error=null;
return 0;
}
public int laszip_open_reader(Stream stream, ref bool is_compressed)
{
if (stream == null)
{
error = "file stream is empty";
return 1;
}
streamin = stream;
try
{
byte[] buffer=new byte[32];
#region read the header variable after variable
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.file_signature";
return 1;
}
if(buffer[0]!='L'&&buffer[1]!='A'&&buffer[2]!='S'&&buffer[3]!='F')
{
error="wrong file_signature. not a LAS/LAZ file.";
return 1;
}
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.file_source_ID";
return 1;
}
header.file_source_ID=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.global_encoding";
return 1;
}
header.global_encoding=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.project_ID_GUID_data_1";
return 1;
}
header.project_ID_GUID_data_1=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.project_ID_GUID_data_2";
return 1;
}
header.project_ID_GUID_data_2=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.project_ID_GUID_data_3";
return 1;
}
header.project_ID_GUID_data_3=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(header.project_ID_GUID_data_4, 0, 8)!=8)
{
error="reading header.project_ID_GUID_data_4";
return 1;
}
if(streamin.Read(buffer, 0, 1)!=1)
{
error="reading header.version_major";
return 1;
}
header.version_major=buffer[0];
if(streamin.Read(buffer, 0, 1)!=1)
{
error="reading header.version_minor";
return 1;
}
header.version_minor=buffer[0];
if(streamin.Read(header.system_identifier, 0, 32)!=32)
{
error="reading header.system_identifier";
return 1;
}
if(streamin.Read(header.generating_software, 0, 32)!=32)
{
error="reading header.generating_software";
return 1;
}
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.file_creation_day";
return 1;
}
header.file_creation_day=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.file_creation_year";
return 1;
}
header.file_creation_year=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.header_size";
return 1;
}
header.header_size=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.offset_to_point_data";
return 1;
}
header.offset_to_point_data=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.number_of_variable_length_records";
return 1;
}
header.number_of_variable_length_records=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 1)!=1)
{
error="reading header.point_data_format";
return 1;
}
header.point_data_format=buffer[0];
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading header.point_data_record_length";
return 1;
}
header.point_data_record_length=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.number_of_point_records";
return 1;
}
header.number_of_point_records=BitConverter.ToUInt32(buffer, 0);
for(int i=0; i<5; i++)
{
if(streamin.Read(buffer, 0, 4)!=4)
{
error=string.Format("reading header.number_of_points_by_return {0}", i);
return 1;
}
header.number_of_points_by_return[i]=BitConverter.ToUInt32(buffer, 0);
}
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.x_scale_factor";
return 1;
}
header.x_scale_factor=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.y_scale_factor";
return 1;
}
header.y_scale_factor=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.z_scale_factor";
return 1;
}
header.z_scale_factor=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.x_offset";
return 1;
}
header.x_offset=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.y_offset";
return 1;
}
header.y_offset=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.z_offset";
return 1;
}
header.z_offset=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.max_x";
return 1;
}
header.max_x=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.min_x";
return 1;
}
header.min_x=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.max_y";
return 1;
}
header.max_y=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.min_y";
return 1;
}
header.min_y=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.max_z";
return 1;
}
header.max_z=BitConverter.ToDouble(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.min_z";
return 1;
}
header.min_z=BitConverter.ToDouble(buffer, 0);
// special handling for LAS 1.3
if((header.version_major==1)&&(header.version_minor>=3))
{
if(header.header_size<235)
{
error=string.Format("for LAS 1.{0} header_size should at least be 235 but it is only {1}", header.version_minor, header.header_size);
return 1;
}
else
{
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.start_of_waveform_data_packet_record";
return 1;
}
header.start_of_waveform_data_packet_record=BitConverter.ToUInt64(buffer, 0);
header.user_data_in_header_size=(uint)header.header_size-235;
}
}
else
{
header.user_data_in_header_size=(uint)header.header_size-227;
}
// special handling for LAS 1.4
if((header.version_major==1)&&(header.version_minor>=4))
{
if(header.header_size<375)
{
error=string.Format("for LAS 1.{0} header_size should at least be 375 but it is only {1}", header.version_minor, header.header_size);
return 1;
}
else
{
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.start_of_first_extended_variable_length_record";
return 1;
}
header.start_of_first_extended_variable_length_record=BitConverter.ToUInt64(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading header.number_of_extended_variable_length_records";
return 1;
}
header.number_of_extended_variable_length_records=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading header.extended_number_of_point_records";
return 1;
}
header.extended_number_of_point_records=BitConverter.ToUInt64(buffer, 0);
for(int i=0; i<15; i++)
{
if(streamin.Read(buffer, 0, 8)!=8)
{
error=string.Format("reading header.extended_number_of_points_by_return[{0}]", i);
return 1;
}
header.extended_number_of_points_by_return[i]=BitConverter.ToUInt64(buffer, 0);
}
header.user_data_in_header_size=(uint)header.header_size-375;
}
}
// load any number of user-defined bytes that might have been added to the header
if(header.user_data_in_header_size!=0)
{
header.user_data_in_header=new byte[header.user_data_in_header_size];
if(streamin.Read(header.user_data_in_header, 0, (int)header.user_data_in_header_size)!=header.user_data_in_header_size)
{
error=string.Format("reading {0} bytes of data into header.user_data_in_header", header.user_data_in_header_size);
return 1;
}
}
#endregion
#region read variable length records into the header
uint vlrs_size=0;
LASzip laszip=null;
if(header.number_of_variable_length_records!=0)
{
header.vlrs=new List<laszip_vlr>();
for(int i=0; i<header.number_of_variable_length_records; i++)
{
header.vlrs.Add(new laszip_vlr());
// make sure there are enough bytes left to read a variable length record before the point block starts
if(((int)header.offset_to_point_data-vlrs_size-header.header_size)<54)
{
warning=string.Format("only {0} bytes until point block after reading {1} of {2} vlrs. skipping remaining vlrs ...", (int)header.offset_to_point_data-vlrs_size-header.header_size, i, header.number_of_variable_length_records);
header.number_of_variable_length_records=(uint)i;
break;
}
// read variable length records variable after variable (to avoid alignment issues)
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading header.vlrs[{0}].reserved", i);
return 1;
}
header.vlrs[i].reserved=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(header.vlrs[i].user_id, 0, 16)!=16)
{
error=string.Format("reading header.vlrs[{0}].user_id", i);
return 1;
}
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading header.vlrs[{0}].record_id", i);
return 1;
}
header.vlrs[i].record_id=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading header.vlrs[{0}].record_length_after_header", i);
return 1;
}
header.vlrs[i].record_length_after_header=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(header.vlrs[i].description, 0, 32)!=32)
{
error=string.Format("reading header.vlrs[{0}].description", i);
return 1;
}
// keep track on the number of bytes we have read so far
vlrs_size+=54;
// check variable length record contents
if(header.vlrs[i].reserved!=0xAABB)
{
warning=string.Format("wrong header.vlrs[{0}].reserved: {1} != 0xAABB", i, header.vlrs[i].reserved);
}
// make sure there are enough bytes left to read the data of the variable length record before the point block starts
if(((int)header.offset_to_point_data-vlrs_size-header.header_size)<header.vlrs[i].record_length_after_header)
{
warning=string.Format("only {0} bytes until point block when trying to read {1} bytes into header.vlrs[{2}].data", (int)header.offset_to_point_data-vlrs_size-header.header_size, header.vlrs[i].record_length_after_header, i);
header.vlrs[i].record_length_after_header=(ushort)(header.offset_to_point_data-vlrs_size-header.header_size);
}
string userid="";
for(int a=0; a<header.vlrs[i].user_id.Length; a++)
{
if(header.vlrs[i].user_id[a]==0) break;
userid+=(char)header.vlrs[i].user_id[a];
}
// load data following the header of the variable length record
if(header.vlrs[i].record_length_after_header!=0)
{
if(userid=="laszip encoded")
{
laszip=new LASzip();
// read the LASzip VLR payload
// U16 compressor 2 bytes
// U32 coder 2 bytes
// U8 version_major 1 byte
// U8 version_minor 1 byte
// U16 version_revision 2 bytes
// U32 options 4 bytes
// I32 chunk_size 4 bytes
// I64 number_of_special_evlrs 8 bytes
// I64 offset_to_special_evlrs 8 bytes
// U16 num_items 2 bytes
// U16 type 2 bytes * num_items
// U16 size 2 bytes * num_items
// U16 version 2 bytes * num_items
// which totals 34+6*num_items
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading compressor";
return 1;
}
laszip.compressor=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading coder";
return 1;
}
laszip.coder=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 1)!=1)
{
error="reading version_major";
return 1;
}
laszip.version_major=buffer[0];
if(streamin.Read(buffer, 0, 1)!=1)
{
error="reading version_minor";
return 1;
}
laszip.version_minor=buffer[0];
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading version_revision";
return 1;
}
laszip.version_revision=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading options";
return 1;
}
laszip.options=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 4)!=4)
{
error="reading chunk_size";
return 1;
}
laszip.chunk_size=BitConverter.ToUInt32(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading number_of_special_evlrs";
return 1;
}
laszip.number_of_special_evlrs=BitConverter.ToInt64(buffer, 0);
if(streamin.Read(buffer, 0, 8)!=8)
{
error="reading offset_to_special_evlrs";
return 1;
}
laszip.offset_to_special_evlrs=BitConverter.ToInt64(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error="reading num_items";
return 1;
}
laszip.num_items=BitConverter.ToUInt16(buffer, 0);
laszip.items=new LASitem[laszip.num_items];
for(int j=0; j<laszip.num_items; j++)
{
laszip.items[j]=new LASitem();
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading type of item {0}", j);
return 1;
}
laszip.items[j].type=(LASitem.Type)BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading size of item {0}", j);
return 1;
}
laszip.items[j].size=BitConverter.ToUInt16(buffer, 0);
if(streamin.Read(buffer, 0, 2)!=2)
{
error=string.Format("reading version of item {0}", j);
return 1;
}
laszip.items[j].version=BitConverter.ToUInt16(buffer, 0);
}
}
else
{
header.vlrs[i].data=new byte[header.vlrs[i].record_length_after_header];
if(streamin.Read(header.vlrs[i].data, 0, header.vlrs[i].record_length_after_header)!=header.vlrs[i].record_length_after_header)
{
error=string.Format("reading {0} bytes of data into header.vlrs[{1}].data", header.vlrs[i].record_length_after_header, i);
return 1;
}
}
}
else
{
header.vlrs[i].data=null;
}
// keep track on the number of bytes we have read so far
vlrs_size+=header.vlrs[i].record_length_after_header;
// special handling for LASzip VLR
if(userid=="laszip encoded")
{
// we take our the VLR for LASzip away
header.offset_to_point_data-=(uint)(54+header.vlrs[i].record_length_after_header);
vlrs_size-=(uint)(54+header.vlrs[i].record_length_after_header);
header.vlrs.RemoveAt(i);
i--;
header.number_of_variable_length_records--;
}
}
}
#endregion
// load any number of user-defined bytes that might have been added after the header
header.user_data_after_header_size=header.offset_to_point_data-vlrs_size-header.header_size;
if(header.user_data_after_header_size!=0)
{
header.user_data_after_header=new byte[header.user_data_after_header_size];
if(streamin.Read(header.user_data_after_header, 0, (int)header.user_data_after_header_size)!=header.user_data_after_header_size)
{
error=string.Format("reading {0} bytes of data into header.user_data_after_header", header.user_data_after_header_size);
return 1;
}
}
// remove extra bits in point data type
if((header.point_data_format&128)!=0||(header.point_data_format&64)!=0)
{
if(laszip==null)
{
error="this file was compressed with an experimental version of LASzip. contact '*****@*****.**' for assistance";
return 1;
}
header.point_data_format&=127;
}
// check if file is compressed
if(laszip!=null)
{
// yes. check the compressor state
is_compressed=true;
if(!laszip.check())
{
error=string.Format("{0} upgrade to the latest release of LAStools (with LASzip) or contact '*****@*****.**' for assistance", laszip.get_error());
return 1;
}
}
else
{
// no. setup an un-compressed read
is_compressed=false;
laszip=new LASzip();
if(!laszip.setup(header.point_data_format, header.point_data_record_length, LASzip.COMPRESSOR_NONE))
{
error=string.Format("invalid combination of point_data_format {0} and point_data_record_length {1}", header.point_data_format, header.point_data_record_length);
return 1;
}
}
// create point's item pointers
for(int i=0; i<laszip.num_items; i++)
{
switch(laszip.items[i].type)
{
case LASitem.Type.POINT14:
case LASitem.Type.POINT10:
case LASitem.Type.GPSTIME11:
case LASitem.Type.RGBNIR14:
case LASitem.Type.RGB12:
case LASitem.Type.WAVEPACKET13:
break;
case LASitem.Type.BYTE:
point.num_extra_bytes=laszip.items[i].size;
point.extra_bytes=new byte[point.num_extra_bytes];
break;
default:
error=string.Format("unknown LASitem type {0}", laszip.items[i].type);
return 1;
}
}
// create the point reader
reader=new LASreadPoint();
if(!reader.setup(laszip.num_items, laszip.items, laszip))
{
error="setup of LASreadPoint failed";
return 1;
}
if(!reader.init(streamin))
{
error="init of LASreadPoint failed";
return 1;
}
laszip=null;
// set the point number and point count
npoints=header.number_of_point_records;
p_count=0;
}
catch
{
error="internal error in laszip_open_reader";
return 1;
}
error=null;
return 0;
}