Re: Re: Reducing the number of bytes...

Mikolaj Machowski on  wrote...
| Anthony Thyssen scripsit:
| > Mikolaj Machowski on  wrote...
| >| BMP doesn't hold any metadata so JPG converted from
them cannot contain
| >| metadata. Conversion any format -> bmp -> any
format is recommended here
| >| way of complete removal of metadata when -strip
isn't enough (and in
| >| many cases it is not).
| >| 
| >
| >
| > In what cases does   -strip  faile to remove all
meta-data
| > when    format -> bmp -> format    does?
| 
| In my cases size of image jpg -> bmp -> jpg is
smaller than jpg ->
| -strip -> jpg.
| 
Hmm that could be for two reasons...

  1/ JPEG is a lossy compressed format,  it is always a
different size.
     It is also a lower quality due to the decode/re-encode
cycle.
     This is the nature of JPEG images

  2/ The JPEG quaility for the JPEG image could have been
reset to 75%
     which naturally results in a MUCH smaller size.
     IM tryes to use the same quality size as the original
input image.

Question...
   How different is the "identify -verbose" output
between  the
stripped JPEG and the convertion via BMP?
Is there lots of extra lines (other than slight color
changes)?

  Anthony Thyssen ( System Programmer )    <A.Thyssengriffith.edu.au>
 -----------------------------------------------------------
------------------
      Kettering's Law :-
             "Logic is an organized way of going wrong,
with confidence."
 -----------------------------------------------------------
------------------
     Anthony's Home is his Castle     http://www.cit.gu.
edu.au/~anthony/
_______________________________________________
Magick-users mailing list
Magick-usersimagemagick.org
http://studio.imagemagick.org/mailman/listinfo/magick
-users