播放mp3

Author: areslp

mp3_toolbox/mp3reader/mp3info.exe

@@ -0,0 +1,54 @@
+function [Y,FS,NBITS,encoding_info,tag_info,out] = mp3read(FILE)
+%MP3READ Read MP3 (".mp3") sound file.
+%    Y = MP3READ(FILE) reads a MP3 file specified by the string FILE,
+%    returning the sampled data in Y. Amplitude values are in the range [-1,+1].
+% 
+%    [Y,FS,NBITS,encoding_info,ID3v1_tag_info] = MP3READ(FILE) returns the sample rate (FS) in Hertz
+%    and the number of bits per sample (NBITS) used to encode the
+%    data in the file.
+%
+%    'encoding_info' is a string containing information about the mp3
+%    encoding used
+%
+%    'ID3v1_tag_info' is a string containing the tag information of the file
+%    (only ID3v1 tag supported in this version)
+%
+% 
+%    Supports two channel or mono encoded data, with up to 16 bits per sample.
+% 
+%    See also MP3WRITE, WAVWRITE, AUREAD, AUWRITE.
+a = length(FILE);
+if a >= 4
+    exten = FILE(a-3:a);
+    if exten ~= '.mp3'
+        FILE = strcat(FILE,'.mp3');
+    end
+end
+if a <= 3
+    FILE = strcat(FILE,'.mp3');
+end
+if exist(FILE) ~= 2
+    error('File not Found')
+end
+%%%%%% Location of the ".exe" Files
+s = which('mp3read.m');
+ww = findstr('mp3read.m',s);
+location = s(1:ww-2);
+%%%%Temporary file%%%%%%
+tmpfile = ['temp.wav'];
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%% Data Decoding  using "mpg123.exe"%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+[stat,raw_info] = dos([location,'\mpg123', ' -w ', tmpfile, ' ', '"',FILE,'"']);
+data_init = findstr(raw_info,'MPEG');
+blocks = findstr(raw_info,'[0:');
+if raw_info(blocks+3) == '0'
+    error('Error while decoding file. File may be corrupted')
+end
+[Y,FS,NBITS] = wavread(tmpfile);    % Load the data and delete temporary file
+delete(tmpfile);
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+tag_info_start = strfind(raw_info,'Title');
+tag_info_end = (strfind(raw_info,'Playing MPEG'))-1;
+tag_info = raw_info(tag_info_start:tag_info_end);
+encoding_info = raw_info(data_init(3):data_init(3)+53);

mp3_toolbox/mp3reader/mp3read.m

@@ -0,0 +1,76 @@
+function mp3write(varargin)
+%MP3WRITE Write MP3 (".mp3") sound file.
+%    MP3WRITE(Y,FS,NBITS,MP3FILE,ENCODING) writes data Y to a MP3
+%    file specified by the file name MP3FILE, with a sample rate
+%    of FS Hz and with NBITS number of bits. Stereo data should 
+%    be specified as a matrix with two columns. 
+%    ENCODING must be specified as an integer number from 1 to 5
+% 
+%   1 = Fixed bit rate 128kbs encoding.
+%   2 = Fixed bit rate jstereo 128kbs encoding, high quality (recommended).
+%   3 = Average bit rate 112kbs encoding.
+%   4 = Fast encode, low quality.
+%   5 = Variable bitrate.
+%
+%   Y,FS and NBITS are mandatory fields. If MP3FILE is not defined the file
+%   name will be 'Default_name.mp3'. If ENCODING is not defined encoding
+%   type '2' will be used by deault.
+%
+%    See also MP3READ, WAVREAD, WAVWRITE.
+if length(varargin) < 3 | length(varargin) > 5
+    error('Unsopported number of argument inputs') 
+end
+Y = varargin{1};
+FS = varargin{2};
+NBITS = varargin{3};
+if NBITS~=8 & NBITS~=16 & NBITS~=24 & NBITS~=32
+    error('Unsopported bit depth')
+end
+if length(varargin) >= 4
+    MP3FILE = varargin{4};
+    if ischar(MP3FILE) ~= 1
+    error('File name is not a string') 
+    end
+else
+    MP3FILE = 'Default_name.mp3';
+    disp('File name = Default_name.mp3')
+end
+
+if isempty(findstr(MP3FILE,'.mp3'))
+    MP3FILE = strcat(MP3FILE,'.mp3');
+end
+
+if length(varargin) == 5
+    ENCODING = varargin{5};
+else
+    ENCODING = '2';
+    disp('Fixed bit rate, joint-stereo, 128 kb/s encoding')
+end
+
+s = which('mp3write.m');
+ww = findstr('mp3write.m',s);
+lame = s(1:ww-2);
+wavwrite(Y,FS,NBITS,strcat(lame,'\temp.wav'));
+tmpfile = strcat(lame,'\temp.wav');
+MP3FILE = strcat(pwd,'\',MP3FILE);
+ENCODING =  num2str(ENCODING);
+switch ENCODING
+    case {'1'}
+        cmd = [lame,'\lame', ' --quiet', ' ', tmpfile, ' ',MP3FILE];
+    case {'2'}
+        cmd = [lame,'\lame', ' --quiet', ' -b 128 ', tmpfile, ' ',MP3FILE];
+    case {'3'}
+        cmd = [lame,'\lame', ' --quiet', ' --abr 112 ', tmpfile, ' ',MP3FILE];
+    case {'4'}
+        cmd = [lame,'\lame', ' --quiet', ' -f ', tmpfile, ' ',MP3FILE];
+    case {'5'}
+        cmd = [lame,'\lame', ' --quiet', ' -h ', ' -V ', tmpfile, ' ',MP3FILE];
+    otherwise
+        error('Encoding parameters not suported') 
+end
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%% Data Encoding  using "Lame.exe"%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+dos(cmd);
+% Delete temporary file
+delete(tmpfile);