FTP upload of intermediate files ok?

[brother7]

Scenario
I take digital photos: CAMERA ORIGINAL = 3008 pixels long

For my Coppermine gallery, I have the following guidelines.
CPG ORIGINAL = 800 pixels long
CPG INTERMEDIATE = 400 pixels long
CPG THUMB = 100 pixels long

Tools
IrfanView 3.95
FTP program

Problem
I'm concerned about the quality of CPG INTERMEDIATE if I let GD/Imagemagick create it from CPG ORIGINAL.  I don't care too much about the quality of CPG THUMB.
I use IrfanView to Batch Resize CAMERA ORIGINAL to CPG ORIGINAL.
In a most common workflow, one would upload CPG ORIGINAL and allow GD/Imagemagick create CPG INTERMEDIATE.  But that's akin to making a copy of a copy.  I propose making a copy from the original, ie use Irfanview to resize CAMERA ORIGINAL to CPG INTERMEDIATE.

Proposed workflow
- Use IrfanView CAMERA ORIGINAL -> CPG ORIGINAL
- Use IrfanView CAMERA ORIGINAL -> CPG INTERMEDIATE  (use 'normal_' filename prefix)
- FTP CPG ORIGINAL and CPG INTERMEDIATE to directory on server
- Coppermine Admin 'Batch Add Files'

Questions
Does the proposed workflow make sense?
With 'Batch Add Files', will only the names of CPG ORIGINAL show or will names of CPG INTERMEDIATE (created by Irfanview and uploaded) also show?
If both names show, is there a workaround to make only the CPG ORIGINAL names show?
What settings in Coppermine Config are necessary to make the proposed workflow work?  For example, Create intermediate pictures = NO.

I hope that all makes sense.  I tried to be as clear as possible.  Thank you in advance for any response.

[Nibbler]

I'd suggest letting coppermine make the resized versions and then overwrite them via FTP with your own. That won't cause any significant problems as far as I can tell. (just that the displayed file sizes would be a little off - easily fixable in the next version)

If you have Create intermediate pictures = NO then coppermine won't display intermediates, even if they are available.

[brother7]

Nibbler, a couple of things you say conflict with my understanding of Coppermine.

'Create intermediate pictures = NO'
You say this will suppress the display of intermediates.
The docs say it will suppress the creation of intermediates, without mention of how it affects the display of any existing intermediates.
So what's the answer?  If set to NO, will intermediates still be displayed if they exist?

overwrite them via FTP
You suggest that I overwrite existing files via FTP.
Everything I've read in this forum recommends against touching any file that are already added to the Coppermine database.

Finally, doing a little more digging, I came across this post by GauGau which seems to answer my initial question... that it's perfectly fine (and for optimal quality, even recommended) to create CPG INTERMEDIATE and CPG THUMB on the client using IrfanView, upload all 3 files via FTP, and 'Batch add files' will behave as desired, ie recognizing the CPG ORIGINAL only.  Am I understanding this correctly?

[Nibbler]

Then he is probably correct, I am not very familiar with batch add. To answer your other point, if you tell coppermine not to create intermediate pics, then it will not attempt to display them. It has no reason to believe that they exist. If you set it to NO then you will never see an intermediate picture anywhere in coppermine, even they exist on the server. Coppermine will say:

if intermediate pics are enabled and this pic is big enough to have a resized version then show the resized version.

As opposed to

if a file called normal_picture exists then display it. - this does not happen.

[brother7]

OK, I just did my little experiment.  Here are the results...

• 'Create intermediate pictures = NO' does not create AND does NOT display intermediate pics. Nibbler, you are correct.
• CPG ORIGINAL, CPG INTERMEDIATE and CPG THUMB can all be uploaded together via FTP.  During 'Batch Add Files', only the main CPG ORIGINAL will appear in the listing.  And with all 3 files in place, 'Insert selected files' goes very fast. 

Thanks.  I think I've got it figured out now.  And a side note...Irfanview is GREAT!

Administrator, feel free to mark the thread 'Solved'.