Maniphest T194395

Rectification failure after adding a map and giving it six control points
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	Shyamal
	May 10 2018, 1:51 PM

Description

I added a map and gave it six control points. The rectification fails.
https://warper.wmflabs.org/maps/2302#Rectify_tab

Event Timeline

Shyamal created this task.May 10 2018, 1:51 PM

Restricted Application added a subscriber: Aklapper. · View Herald TranscriptMay 10 2018, 1:51 PM

Aklapper renamed this task from Rectification failure to Rectification failure after adding a map and giving it six control points.May 10 2018, 8:29 PM

Susannaanas assigned this task to Chippyy.May 26 2018, 4:43 PM

Hi, many thanks for this bug report.

gdal_translate -a_srs '+init=epsg:4326' -of VRT /home/warperdata/src/Himalayan_river_catchments.jpg.tif /home/warperdata/dst/2302_temp.vrt  -gcp 249.0261904762, 1214.95119047615, 60.0, 24.0 -gcp 398.63452380954, 249.8952380952, 60.0, 45.0 -gcp 1801.0071428572, 253.1833333334, 100.0, 45.0 -gcp 1960.4797619045, 1218.2392857142, 100.0, 24.0 -gcp 931.30595238085, 1272.49285714273, 76.0, 24.0 -gcp 962.54285714276, 294.2845238094, 76.0, 45.0

gdalwarp    -rn    -dstalpha  -s_srs 'EPSG:4326' /home/warperdata/dst/2302_temp.vrt /home/warperdata/dst/2302.tif -co TILED=YES -co COMPRESS=LZW

This fails, "ERROR 1: Failed to compute GCP transform: Transform is not solvable"

gdalwarp    -rn    -order 1  -dstalpha  -s_srs 'EPSG:4326' /home/warperdata/dst/2302_temp.vrt /home/warperdata/dst/2302.tif -co TILED=YES -co COMPRESS=LZW

Works

Screenshot_2018-06-11_15-30-28.png (827×1 px, 663 KB)

The work around was to select 1st Polynomial in the Rectify Method (see attached screenshot), or to add more points to the image.

Ideally the system should check to see if there is that error and try the first polynomial. I'll make an issue on github.

tracking this here: https://github.com/timwaters/mapwarper/issues/156

• Vvjjkkii renamed this task from Rectification failure after adding a map and giving it six control points to g7caaaaaaa.Jul 1 2018, 1:11 AM

• Vvjjkkii reopened this task as Open.

• Vvjjkkii removed Chippyy as the assignee of this task.

• Vvjjkkii triaged this task as High priority.

• Vvjjkkii added projects: CheckUser, Connected-Open-Heritage-Batch-uploads (RAÄ-KMB_1_2017-02), Tamil-Sites, Gamepress, Hashtags, Jade, KartoEditor, Language-2018-Apr-June, New-Editor-Experiences, Mail, TCB-Team (now WMDE-TechWish).

• Vvjjkkii updated the task description. (Show Details)

• Vvjjkkii edited subscribers, added: Chippyy; removed: Aklapper.

CommunityTechBot renamed this task from g7caaaaaaa to Rectification failure after adding a map and giving it six control points.Jul 2 2018, 4:19 PM

CommunityTechBot closed this task as Resolved.

CommunityTechBot assigned this task to Chippyy.

CommunityTechBot raised the priority of this task from High to Needs Triage.

CommunityTechBot updated the task description. (Show Details)

CommunityTechBot removed projects: TCB-Team (now WMDE-TechWish), Mail, New-Editor-Experiences, Language-2018-Apr-June, KartoEditor, Jade, Hashtags, Gamepress, Tamil-Sites, Connected-Open-Heritage-Batch-uploads (RAÄ-KMB_1_2017-02), CheckUser.

CommunityTechBot edited subscribers, added: Aklapper; removed: Chippyy.

	F21824220: Screenshot_2018-06-11_15-30-28.png
	Jun 11 2018, 2:35 PM

Rectification failure after adding a map and giving it six control pointsClosed, ResolvedPublicActions

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Rectification failure after adding a map and giving it six control points
Closed, ResolvedPublic
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