Bug report #12795
Georeferencer generates incorrect GDAL script when input file is JPG
Status: | Closed | ||
---|---|---|---|
Priority: | Normal | ||
Assignee: | - | ||
Category: | C++ plugins/Georeferencer | ||
Affected QGIS version: | 2.8.5 | Regression?: | No |
Operating System: | Easy fix?: | No | |
Pull Request or Patch supplied: | No | Resolution: | end of life |
Crashes QGIS or corrupts data: | No | Copied to github as #: | 20891 |
Description
Problem:
When georeferencing a JPEG image QGIS return telling the transformation could not be made.
According to the GDAL script QGIS can generate, the process is split into two steps:
gdal_translate
gdalwarp
Script:
gdal_translate -of GTiff -gcp ... -gcp ... "original.jpg" "temp.jpg" gdalwarp -r near -tps -co COMPRESS=LZW -dstalpha "temp.jpg" "result.tif"
The input and output argument provided to gdal_translate
is both with JPG extension, while the -of
argument is GTiff
. gdalwarp
cannot handle a GeoTIFF image with JPG extension.
Solution:
So either should the first process set the -of
argument to JPEG (in this instance) or change the output extension to TIF.
History
#1
Updated by Nyall Dawson about 9 years ago
- Status changed from Open to Feedback
I can't reproduce - is this only when using the generated GDAL scripts? Does the georeferencing work OK from within QGIS itself?
#2
Updated by Casper Børgesen about 9 years ago
Nyall Dawson wrote:
I can't reproduce - is this only when using the generated GDAL scripts? Does the georeferencing work OK from within QGIS itself?
I reported this problem because my users couldn't use QGIS directly and I had to create a batch script to solve the problem. Thats why I discovered the JPEG/TIFF problem.
I have a rather large (30MB) JPEG image and when I use QGIS to georeference it, I get the error "Failed to compute GCP transform. Transform is not solvable.". When I correct the JPEG/TIFF problem in the correspondig GDAL script generated by QGIS, the same transform succeeds. Thats why I thought the problem indeed was the extension.
I have just tried though with a small JPEG image and QGIS was able to transform it. I have tried both in QGIS f4c3f3d (latest weekly for windows).
Could this be image size related somehow?
#3
Updated by Nyall Dawson about 9 years ago
So... to clarify, there's two issues. One is that the generated GDAL script is wrong, the second is that QGIS can't transform your file. Can you open a second issue for the failing to transform issue, and attach a link to the data and GCP points file?
#4
Updated by Nyall Dawson about 9 years ago
- Subject changed from Georeferencer sets wrong extension when inputting JPEG to Georeferencer generates incorrect GDAL script when input file is JPG
#5
Updated by Giovanni Manghi over 8 years ago
- Operating System deleted (
windows) - Affected QGIS version changed from 2.8.1 to 2.8.5
- Status changed from Feedback to Open
#6
Updated by Giovanni Manghi over 7 years ago
- Regression? set to No
- Easy fix? set to No
#7
Updated by Giovanni Manghi over 5 years ago
- Resolution set to end of life
- Status changed from Open to Closed
End of life notice: QGIS 2.18 LTR
Source:
http://blog.qgis.org/2019/03/09/end-of-life-notice-qgis-2-18-ltr/