Opened 11 years ago

Closed 9 years ago

#162 closed task (fixed)

GeoTiff to JPEG conversion

Reported by: mark1 Owned by: mark1
Priority: alpha 4 high Milestone: The Glorious Future
Component: Processing: general Keywords:
Cc: Other processors:

Description

Need a simple way to convert GeoTIFF images to JPEG

Change History (8)

comment:1 Changed 11 years ago by mark1

Written a simple python script to convert GeoTIFFS to JPEGS, simple linear contrast stretch doesn't work to well.

Trying a linear 95% stretch...still not great.

RGB->HSL, stretch L (linear 95%), HSL->RGB ...also not great!

comment:2 Changed 11 years ago by mark1

  • Owner set to mark1

Looking at gtviewer code suggests same stretch algorithm is being applied. Have tried "hard wiring" gtviewer scale parameters within python script and gives same image. This suggests that the histogram method in python script is not accurate enough, will implement a slow counting method.

comment:3 Changed 11 years ago by mark1

Now have a working version of script, tested for small files (tifs of around 50MB) but may fall down on large tifs (ATM). Working version is GTIFF2JPEG_3

comment:4 Changed 11 years ago by mark1

Has been tested on files upto 330MB and seems to work ok without crashing.

comment:5 Changed 11 years ago by mark1

Have now implemented a method to handle larger tif files, and has worked for images upto 825MB. Not tested larger files.

comment:6 Changed 11 years ago by mark1

Filename is gtiff2jpg_v4.py

comment:7 Changed 11 years ago by mark1

Have copied the script into the arsf usr/bin , called gtiff2jpg.py

comment:8 Changed 9 years ago by mark1

  • Resolution set to fixed
  • Status changed from new to closed
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