Do you use lossless JPEG recompression tools?

There are a number of tools available which can do "lossless"
compression of jpeg files, they get around 20-25% compression. There
are both commercial/proprietary (StufIt) and free/open-source options
(PackJPG, PAQ etc...).

Have you tried any such tool? Do you use any?

I am in process of publishing an image compression benchmark and want
to know what is in actual popular use and what all is only
academically interesting.

And if not, then why not? what do you think is missing in them that
would make you change your mind?

Sachin Garg [India]
www.sachingarg.com | www.c10n.info

On Fri, 18 Jan 2008 10:21:18 -0800 (PST), Sachin Garg
wrote in
:

There are a number of tools available which can do "lossless"
compression of jpeg files, they get around 20-25% compression. There
are both commercial/proprietary (StufIt) and free/open-source options
(PackJPG, PAQ etc...).

Have you tried any such tool? Do you use any?

I am in process of publishing an image compression benchmark and want
to know what is in actual popular use and what all is only
academically interesting.

And if not, then why not? what do you think is missing in them that
would make you change your mind?

I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

On Jan 19, 12:17 am, John Navas wrote:
On Fri, 18 Jan 2008 10:21:18 -0800 (PST), Sachin Garg
wrote in
:

There are a number of tools available which can do "lossless"
compression of jpeg files, they get around 20-25% compression. There
are both commercial/proprietary (StufIt) and free/open-source options
(PackJPG, PAQ etc...).

Have you tried any such tool? Do you use any?

I am in process of publishing an image compression benchmark and want
to know what is in actual popular use and what all is only
academically interesting.

And if not, then why not? what do you think is missing in them that
would make you change your mind?

I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

Yep, they are a bit slow. Around 12 seconds per 8 MegaPixel Jpeg on my
Pentium4.

Is it too slow even for backups? Will your opinion change if it was,
say, 1 sec per image?

Sachin Garg [India]
www.sachingarg.com | www.c10n.info

On Fri, 18 Jan 2008 12:35:46 -0800 (PST), Sachin Garg
wrote in
:

On Jan 19, 12:17 am, John Navas wrote:

I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

Yep, they are a bit slow. Around 12 seconds per 8 MegaPixel Jpeg on my
Pentium4.

Is it too slow even for backups?

Yes -- I like to be able to access my backups directly.

Will your opinion change if it was,
say, 1 sec per image?

It's not only the overhead, it's the hassle. What I'd rather have is an
alternative to JPEG that has the extra compression built-in.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

"John Navas" a écrit dans le message de news:
...
On Fri, 18 Jan 2008 12:35:46 -0800 (PST), Sachin Garg
wrote in
:

On Jan 19, 12:17 am, John Navas wrote:

I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

Yep, they are a bit slow. Around 12 seconds per 8 MegaPixel Jpeg on my
Pentium4.

Is it too slow even for backups?

Yes -- I like to be able to access my backups directly.

Will your opinion change if it was,
say, 1 sec per image?

It's not only the overhead, it's the hassle. What I'd rather have is an
alternative to JPEG that has the extra compression built-in.


Time for backups are not too important, I copy my files to another machine,
to a portable USB drive and I have just added a network drive (500Gb). Just
start a copy before going to bed and sleep over it. It is more important
for me to be able to read old files rather than rely on a piece of software
that may not be aroung or supported on a future processor or operating
system.

Jean

On Fri, 18 Jan 2008 17:51:05 -0500, "jean" wrote:

Time for backups are not too important, I copy my files to another machine,
to a portable USB drive and I have just added a network drive (500Gb). Just
start a copy before going to bed and sleep over it.

Jean,

It is relatively easy to have a backup done automatically every night when
you are sleeping. The software I use is: http://www.smsync.com/ which I saw
recommended by a computer columnist (probably the one that is quoted on
their home page).

What I haven't done is to set it up to back up the most important files
nightly to one of my web sites, where I have spare storage.

Don www.donwiss.com (e-mail link at home page bottom).

On Jan 19, 1:49 am, John Navas wrote:
On Fri, 18 Jan 2008 12:35:46 -0800 (PST), Sachin Garg
wrote in
:

On Jan 19, 12:17 am, John Navas wrote:
I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

Yep, they are a bit slow. Around 12 seconds per 8 MegaPixel Jpeg on my
Pentium4.

Is it too slow even for backups?

Yes -- I like to be able to access my backups directly.

Will your opinion change if it was,
say, 1 sec per image?

It's not only the overhead, it's the hassle. What I'd rather have is an
alternative to JPEG that has the extra compression built-in.

Yep, this makes sense.

Can I have any more opinions? Is anyone else here using these tools?

Sachin Garg [India]
www.sachingarg.com | www.c10n.info

On Jan 19, 3:51 am, "jean" wrote:
"John Navas" a écrit dans le message de news:
...



On Fri, 18 Jan 2008 12:35:46 -0800 (PST), Sachin Garg
wrote in
:

On Jan 19, 12:17 am, John Navas wrote:

I don't use them because disk space is so cheap that I don't want any
additional processing overhead.

Yep, they are a bit slow. Around 12 seconds per 8 MegaPixel Jpeg on my
Pentium4.

Is it too slow even for backups?

Yes -- I like to be able to access my backups directly.

Will your opinion change if it was,
say, 1 sec per image?

It's not only the overhead, it's the hassle. What I'd rather have is an
alternative to JPEG that has the extra compression built-in.

Time for backups are not too important, I copy my files to another machine,
to a portable USB drive and I have just added a network drive (500Gb). Just
start a copy before going to bed and sleep over it. It is more important
for me to be able to read old files rather than rely on a piece of software
that may not be aroung or supported on a future processor or operating
system.

This concern might be true for proprietary formats from unknown
companies, but is it really a concern when its an open-source solution
(or if its from a dependable company)?

Sachin Garg [India]
www.sachingarg.com | www.c10n.info

Sachin Garg wrote:
[]
Can I have any more opinions? Is anyone else here using these tools?

Sachin Garg [India]
www.sachingarg.com | www.c10n.info

Not using - never seen any need.

David

Sachin Garg wrote:
[]
This concern might be true for proprietary formats from unknown
companies, but is it really a concern when its an open-source solution
(or if its from a dependable company)?

Any proprietary format is dubious - look at the difficulties in reading
old word-processor formats. Open-source can be the kiss-of-death for a
project, as the programmers loose interest and move onto something else.
Seen that happen time after time.

Stick to standard JPEG.

David