MATLAB对ply文件格式读取及显示

1、MATLAB对ply文件格式的读取和显示首先是这个ply_read.m文件plain view plain copy print?在CODE上查看代码片派生到我的代码片function Elements, varargout = PLY_READ ( Path, Str ) %*80 % % PLY_READ reads a PLY 3D data file. % % DATA,COMMENTS = PLY_READ(FILENAME) reads a version 1.0 PLY file % FILENAME and returns a structure DATA. The field

2、s in this structure % are defined by the PLY header; each element type is a field and each % element property is a subfield. If the file contains any comments, % they are returned in a cell string array COMMENTS. % % TRI,PTS = PLY_READ(FILENAME,tri) or % TRI,PTS,DATA,COMMENTS = PLY_READ(FILENAME,tri

3、) converts vertex % and face data into triangular connectivity and vertex arrays. The % mesh can then be displayed using the TRISURF command. % % Note: This function is slow for large mesh files (+50K faces), % especially when reading data with list type properties. % % Example: % Tri,Pts = PLY_READ

4、(cow.ply,tri); % Tri,Pts = PLY_READ(bunny.ply,tri); % trisurf(Tri,Pts(:,1),Pts(:,2),Pts(:,3); % colormap(gray); axis equal; % % Discussion: % % The original version of this program had a mistake that meant it % did not properly triangulate files whose faces were not already triangular. % This has be

5、en corrected (JVB, 25 February 2007). % % Glenn Ramsey pointed out and corrected a problem that occurred % with an uninitialized value of Type2, 27 August 2012. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 27 August 2012 % % Author: % % Pascal Getreuer 20

6、04 % % Parameters: % % Local Parameters: % % COMMENTS, any comments from the file. % % ELEMENTCOUNT, the number of each type of element in file. % % ELEMENTS, the element data. % % PROPERTYTYPES, the element property types. % % SIZEOF, size in bytes of each type. % % % Open the input file in read te

7、xt mode. % fid, Msg = fopen ( Path, rt ); if ( fid = -1 ) error ( Msg ); end Buf = fscanf ( fid, %s, 1 ); if ( strcmp ( Buf, ply ) ) fclose ( fid ); error(Not a PLY file.); end % % Read the header. % Position = ftell(fid); Format = ; NumComments = 0; Comments = ; NumElements = 0; NumProperties = 0;

8、Elements = ; ElementCount = ; PropertyTypes = ; ElementNames = ; % list of element names in the order they are stored in the file PropertyNames = ; % structure of lists of property names while ( 1 ) % % Read a line from the file. % Buf = fgetl ( fid ); BufRem = Buf; Token = ; Count = 0; % % Split th

9、e line into tokens. % while ( isempty(BufRem) ) tmp, BufRem = strtok(BufRem); % % Count the tokens. % if ( isempty ( tmp ) ) Count = Count + 1; TokenCount = tmp; end end % % Parse the line. % if ( Count ) switch lower ( Token1 ) % % Read the data format. % case format if ( 2 = Count ) Format = lower

10、 ( Token2 ); if ( Count = 3 & strcmp ( Token3, 1.0 ) ) fclose ( fid ); error(Only PLY format version 1.0 supported.); end end % % Read a comment. % case comment NumComments = NumComments + 1; CommentsNumComments = ; for i = 2 : Count CommentsNumComments = CommentsNumComments,Tokeni, ; end % % Read a

11、n element name. % case element if ( 3 = 3 ) NumProperties = NumProperties + 1; eval(tmp=isfield(Elements.,CurElement,TokenCount);,. fclose(fid);error(Error reading property: ,Buf); if ( tmp ) error(Duplicate property name, ,CurElement,.,Token2,.); end % % Add property subfield to Elements. % eval(El

12、ements.,CurElement,.,TokenCount,=;, . fclose(fid);error(Error reading property: ,Buf); % % Add property subfield to PropertyTypes and save type. % eval(PropertyTypes.,CurElement,.,TokenCount,=Token2:Count-1;, . fclose(fid);error(Error reading property: ,Buf); % % Record property name order. % eval(P

13、ropertyNames.,CurElement,NumProperties=TokenCount;, . fclose(fid);error(Error reading property: ,Buf); else fclose ( fid ); if ( isempty(CurElement) ) error(Property definition without element definition: ,Buf); else error(Bad property definition: ,Buf); end end % % End of header. % case end_header

14、break; end end end % % Set reading for specified data format. % if ( isempty ( Format ) ) warning(Data format unspecified, assuming ASCII.); Format = ascii; end switch Format case ascii Format = 0; case binary_little_endian Format = 1; case binary_big_endian Format = 2; otherwise fclose ( fid ); err

15、or(Data format ,Format, not supported.); end % % Read the rest of the file as ASCII data. % if ( Format ) Buf = fscanf ( fid, %f ); BufOff = 1; else % % .or, close the file, and reopen in read binary mode. % fclose ( fid ); % % Reopen the binary file as LITTLE_ENDIAN or BIG_ENDIAN. % if ( Format = 1

16、 ) fid = fopen ( Path, r, ieee-le.l64 ); else fid = fopen ( Path, r, ieee-be.l64 ); end % % Find the end of the header again. % Using ftell on the old handle doesnt give the correct position. % BufSize = 8192; Buf = blanks(10), char(fread(fid,BufSize,uchar) ; i = ; tmp = -11; while ( isempty(i) ) i

17、= findstr(Buf,end_header,13,10); % look for end_header + CR/LF i = i,findstr(Buf,end_header,10); % look for end_header + LF if ( isempty(i) ) tmp = tmp + BufSize; Buf = Buf(BufSize+1:BufSize+10),char(fread(fid,BufSize,uchar); end end % % seek to just after the line feed % fseek ( fid, i + tmp + 11 +

18、 (Buf(i + 10) = 13), -1 ); end % % Read element data. % % PLY and MATLAB data types (for fread) % PlyTypeNames = char,uchar,short,ushort,int,uint,float,double, . char8,uchar8,short16,ushort16,int32,uint32,float32,double64; MatlabTypeNames = schar,uchar,int16,uint16,int32,uint32,single,double; SizeOf

19、 = 1,1,2,2,4,4,4,8; for i = 1 : NumElements % % get current element property information % eval(CurPropertyNames=PropertyNames.,ElementNamesi,;); eval(CurPropertyTypes=PropertyTypes.,ElementNamesi,;); NumProperties = size(CurPropertyNames,2); % fprintf(Reading %s.n,ElementNamesi); % % Read ASCII dat

20、a. % if ( Format ) for j = 1 : NumProperties Token = getfield(CurPropertyTypes,CurPropertyNamesj); if ( strcmpi(Token1,list) ) Type(j) = 1; else Type(j) = 0; end % % Glenn Ramsey 20120827 % Initialise Type2 to prevent uninitialised value error. % Type2j = ; end % % Parse the buffer. % if ( any(Type)

21、 ) % no list types Data = reshape ( . Buf(BufOff:BufOff+ElementCount(i)*NumProperties-1), . NumProperties, ElementCount(i) ); BufOff = BufOff + ElementCount(i) * NumProperties; else ListData = cell(NumProperties,1); for k = 1 : NumProperties ListDatak = cell(ElementCount(i),1); end % % list type % f

22、or j = 1 : ElementCount(i) for k = 1 : NumProperties if ( Type(k) ) Data(j,k) = Buf(BufOff); BufOff = BufOff + 1; else tmp = Buf(BufOff); ListDatakj = Buf(BufOff+(1:tmp); BufOff = BufOff + tmp + 1; end end end end % % Read binary data. % else % translate PLY data type names to MATLAB data type names

23、 ListFlag = 0; % = 1 if ere is a list type SameFlag = 1; % = 1 if all types are the same for j = 1 : NumProperties Token = getfield(CurPropertyTypes,CurPropertyNamesj); % % Non-list type. % if ( strcmp(Token1,list ) ) tmp = rem(strmatch(Token1,PlyTypeNames,exact)-1,8)+1; if ( isempty(tmp) ) TypeSize

24、(j) = SizeOf(tmp); Typej = MatlabTypeNamestmp; TypeSize2(j) = 0; Type2j = ; SameFlag = SameFlag & strcmp(Type1,Typej); else fclose(fid); error(Unknown property data type, ,Token1, in , . ElementNamesi,.,CurPropertyNamesj,.); end else % list type if ( length(Token) = 3 ) ListFlag = 1; SameFlag = 0; t

25、mp = rem(strmatch(Token2,PlyTypeNames,exact)-1,8)+1; tmp2 = rem(strmatch(Token3,PlyTypeNames,exact)-1,8)+1; if ( isempty(tmp) & isempty(tmp2) ) TypeSize(j) = SizeOf(tmp); Typej = MatlabTypeNamestmp; TypeSize2(j) = SizeOf(tmp2); Type2j = MatlabTypeNamestmp2; lse fclose(fid); error(Unknown property da

26、ta type, list ,Token2, ,Token3, in , . ElementNamesi,.,CurPropertyNamesj,.); end else fclose(fid); error(Invalid list syntax in ,ElementNamesi,.,CurPropertyNamesj,.); end end end % read file if ( ListFlag ) % % No list types, all the same type (fast) % if ( SameFlag ) Data = fread(fid,NumProperties,

27、ElementCount(i),Type1); % % No list types, mixed type. % else Data = zeros(ElementCount(i),NumProperties); for j = 1 : ElementCount(i) for k = 1 : NumProperties Data(j,k) = fread(fid,1,Typek); end end end else ListData = cell(NumProperties,1); for k = 1 : NumProperties ListDatak = cell(ElementCount(

28、i),1); end if ( NumProperties = 1 ) BufSize = 512; SkipNum = 4; j = 0; % % List type, one property (fast if lists are usually the same length) % while ( j ElementCount(i) ) BufSize = min(ElementCount(i)-j,BufSize); Position = ftell(fid); % % Read in BufSize count values, assuming all counts = SkipNu

29、m % Buf,BufSize = fread(fid,BufSize,Type1,SkipNum*TypeSize2(1); Miss = find(Buf = SkipNum); % find first count that is not SkipNum fseek(fid,Position + TypeSize(1),-1); % seek back to after first count if ( isempty(Miss) ) % all counts are SkipNum Buf = fread(fid,SkipNum,BufSize,int2str(SkipNum),*,T

30、ype21,TypeSize(1); fseek(fid,-TypeSize(1),0); % undo last skip for k = 1:BufSize ListData1j+k = Buf(k,:); end j = j + BufSize; BufSize = floor(1.5*BufSize); else % % Some counts are SkipNum. % if ( 1 1 & strcmpi(Str,Tri) ) | nargout 2 ) % % Find vertex element field % Name = vertex,Vertex,point,Poin

31、t,pts,Pts; Names = ; for i = 1 : length(Name) if ( any ( strcmp ( ElementNames, Namei ) ) ) Names = getfield(PropertyNames,Namei); Name = Namei; break; end end if ( any(strcmp(Names,x) & any(strcmp(Names,y) & any(strcmp(Names,z) ) eval(varargout1=Elements.,Name,.x,Elements.,Name,.y,Elements.,Name,.z

32、;); else varargout1 = zeros(1,3); end varargout1 = varargout1; varargout2 = Elements; varargout3 = Comments; Elements = ; % % Find face element field % Name = face,Face,poly,Poly,tri,Tri; Names = ; for i = 1 : length(Name) if ( any(strcmp(ElementNames,Namei) ) Names = getfield(PropertyNames,Namei);

33、Name = Namei; break; end end if ( isempty(Names) ) % find vertex indices property subfield PropertyName = vertex_indices,vertex_indexes,vertex_index,indices,indexes; for i = 1 : length(PropertyName) if ( any(strcmp(Names,PropertyNamei) ) PropertyName = PropertyNamei; break; end end % % Convert face

34、index list to triangular connectivity. % if ( iscell(PropertyName) ) eval(FaceIndices=varargout2.,Name,.,PropertyName,;); N = th(FaceIndices); Elements = zeros(3,N*2); Extra = 0; for k = 1 : N Elements(1:3,k) = FaceIndicesk(1:3); % % The original code had an error in the following loop. % for j = 4 : length