BLOB Extraction for JPG files

Hi,

 We are trying to extract the BLOB (JPG) to a local D drive and trying to view the .JPG file but it is not displaing properly.Please let me know if any one had the similary issue and able to resolve.

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We used the below code to extract the JPG file.
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declare
t_out_file UTL_FILE.file_type;
t_buffer VARCHAR2(32767);
t_amount BINARY_INTEGER := 1000;
t_pos INTEGER := 1;
t_clob_len INTEGER;
P_DATA BLOB;
P_DIR VARCHAR2(100) := 'IMAGES';
P_FILE VARCHAR2(100) := 'TEST.jpg';
BEGIN
select pict_test into P_DATA from test;
-- INSERT INTO BLOB_TABLE VALUES(P_DATA);