Export JPEGs from blobs (not using interMedia)

Question

I am storing JPEGs in blobs using the following stored procedure:
CREATE OR REPLACE PROCEDURE load_file (fname in varchar2, sp_id in varchar2, objectid in varchar2) IS
src_file BFILE;
dst_file BLOB;
lgh_file BINARY_INTEGER;
BEGIN
src_file := bfilename('CTEMP', fname);
-- blob reserve
delete from image_table where spill_id = sp_id;
INSERT INTO image_table (spill_id, rp_objectid, image) VALUES (sp_id,objectid,EMPTY_BLOB()) RETURNING image INTO dst_file;
-- lock blob for input
SELECT image INTO dst_file FROM image_table WHERE spill_id = sp_id FOR UPDATE;
-- file open
dbms_lob.fileopen(src_file, dbms_lob.file_readonly);
-- length of file
lgh_file := dbms_lob.getlength(src_file);
-- input file
dbms_lob.loadfromfile(dst_file, src_file, lgh_file);
-- update table
UPDATE image_table SET spill_id = sp_id, image = dst_file WHERE spill_id = sp_id;
delete from image_table where image is null;
-- Alle Files close
dbms_lob.filecloseall;
-- dbms_lob.fileclose(src_file);
COMMIT;
END load_file;
I need to export the JPEGs back out to .JPG files. How can I do that?
I am running Oracle 8.1.7 on Windows 2000.
Thanks
Dave

Answer 1

Here's how I'm doing it. We're using the web, so I'm just referencing this procedure as part of an <IMG SRC="||get_empimg?empno_in='nnnnnnn'> tag in HTML.
I'm storing our mime-type in the file, but you'd need to specify an "image/pjpeg" mimetype if you're not storing it on an image by image basis somewhere.
create or replace procedure get_empimg(empno_in number) as
vblob blob;
buffer raw(32000);
buffer_size integer := 32000;
offset integer := 1;
length number;
mimetype varchar2(40);
begin
select emp_pic, emp_pic_mime into vblob, mimetype
from web_emp_tbl
where emp_no = empno_in;
owa_util.mime_header(mimetype);
length := dbms_lob.getlength(vblob);
while offset < length loop
dbms_lob.read(vblob,buffer_size,offset,buffer);
htp.prn(utl_raw.cast_to_varchar2(buffer));
offset := offset + buffer_size;
end loop;
end;