Allow multiple -scale switches in gdal_translate

[lpinner]

It would be useful if gdal_translate could accept multiple -scale switches to allow different scales to be applied to individual bands.

Suggested logic:

• if a single -scale switch is passed, apply to all bands (or only those specified by -b switch) - i.e. current logic
• if N -scale switches are passed and there are N bands, apply -scale switches in the order they were passed to bands in dataset order
• if N -scale and N -b switches are passed, apply -scale switches in the order they were passed to bands in the order they were passed in by -b switches
• if N -scale and a different number of -b switches are passed, raise an error

[warmerdam]

It really feels like this going to end up overcomplicating the gdal_translate commandline. You could process each band to a separate file, doing the -scale as you go, then remerge afterwards.

Note that VRTs can also be used to apply per band scaling if so desired.

[lpinner]

Fair enough. That's what I do now (separate vrts then merge). I was just hoping to be able to do it in one hit (aka being lazy), I'll go away and write a wrapper script instead.

Luke

[Kyle Shannon]

Luke, See r26097, seems like it may be what you are looking for. I don't know if EvenR knows about this ticket.

[Even Rouault]

Ah right. I did implement this without knowing about the ticket.