<div dir="ltr"><br><div class="gmail_extra"><br><br><div class="gmail_quote">On Mon, Jun 30, 2014 at 3:07 PM, Even Rouault <span dir="ltr"><<a href="mailto:even.rouault@mines-paris.org" target="_blank">even.rouault@mines-paris.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br><div class="">
<br>
</div>That might the problem. If you create the GCPs on the PDF and not on the PNG,<br>
and that the PDF has rotation, pdftoppm I think will apply the rotation, hence<br>
the axis swapping.<br></blockquote><div> </div><div>Remember, I'm using the PNG I've created for all gdal operations, gdal never interacts with the source PDF<br> <br></div><div>I'm probably fundamentally misunderstanding some aspect of the command lines I'm using in gdal*. My end goal is to get the necessary affine transformation information to display the PNG I create in step 3a properly in a separate Android moving-map application (eg. your current position displayed on the diagram as you move around the airport)<br>
<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Well I'm really confused by what you are trying to do.<br>
<br>
For a better understanding, you should perhaps provide the PDF and all exact<br>
command lines you are typing.<br></blockquote></div><br></div><div class="gmail_extra">Here's a step-by-step with links to relevant files for a landscape diagram (SFO) <br><br></div><div class="gmail_extra">1. Get source PDFs from the Federal Aviation Administrator (FAA)<br>
<a href="https://drive.google.com/file/d/0B4EbUsrclSoDeXdmM3gyV29WN0U/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDeXdmM3gyV29WN0U/edit?usp=sharing</a><br><br></div><div class="gmail_extra">2. Run my utility. <br>
<br>3a. It converts the PDF to a PNG,<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDMTlDZzQzeDJWU1U/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDMTlDZzQzeDJWU1U/edit?usp=sharing</a><br><br>
3b. create GCPs for GDAL based on the coordinates within the PNG (hard to see but green circles mark the GCPs chosen to correspond to the lat/lon shown on diagram)<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDWUtqNVgtWFUwa0k/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDWUtqNVgtWFUwa0k/edit?usp=sharing</a><br>
<br></div><div class="gmail_extra">3c. gdal_translate the PNG file based on the GCPs we found to an intermediate VRT<br>gdal_translate -q -of VRT -strict -a_srs EPSG:4326 -gcp 1017.14863049096 1800.51717680381 -122.4 37.6166666666667 -gcp 337.854728682168 1260.25 -122.383333333333 37.6333333333333 -gcp 1017.14863049095 1260.25 -122.383333333333 37.6166666666667 -gcp 1017.14863049096 720.166666666667 -122.366666666667 37.6166666666667 -gcp 337.854728682172 720.166666666667 -122.366666666667 37.6333333333333 -gcp 337.854728682172 1800.33895140302 -122.4 37.6333333333333 './dtpp/00375AD.png' './dtpp/CA-SFO-00375AD-PDF-AIRPORT-DIAGRAM.vrt'<br>
<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDX2hzTTBsY1c5dXM/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDX2hzTTBsY1c5dXM/edit?usp=sharing</a><br><br>3d. gdalwarp the intermediate VRT to the final VRT<br>
gdalwarp -q -of VRT -t_srs EPSG:4326 -order 1 -overwrite ''./dtpp/CA-SFO-00375AD-PDF-AIRPORT-DIAGRAM.vrt'' './dtpp/warpedCA-SFO-00375AD.PDF-AIRPORT DIAGRAM.vrt'<br><br></div><div class="gmail_extra">
<a href="https://drive.google.com/file/d/0B4EbUsrclSoDTmNDanFmbkVvVm8/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDTmNDanFmbkVvVm8/edit?usp=sharing</a><br><br></div><div class="gmail_extra">Here's the process for a portrait one<br>
<br><div class="gmail_extra">1. Get source PDFs from the Federal Aviation Administrator (FAA)<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDMjNPOVBPT01JS1U/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDMjNPOVBPT01JS1U/edit?usp=sharing</a><br>
</div><div class="gmail_extra"><br>2. Run my utility. <br><br>3a. It converts the PDF to a PNG,<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDTUZNY2RKaVVHMDQ/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDTUZNY2RKaVVHMDQ/edit?usp=sharing</a><br>
<br>3b.
create GCPs for GDAL based on the coordinates within the PNG (hard to
see but green circles mark the GCPs chosen to correspond to the lat/lon
shown on diagram)<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDbHNyTnhGczh3RDA/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDbHNyTnhGczh3RDA/edit?usp=sharing</a><br><br></div><div class="gmail_extra">
3c. gdal_translate the PNG file based on the GCPs we found to an intermediate VRT<br> gdal_translate -q -of VRT -strict -a_srs EPSG:4326 -gcp 310.408626924008 1496.72390271202 -77.3333333333333 37.5 -gcp 976.562655349203 660.697730425566 -77.3166666666667 37.5166666666667 -gcp 310.523817613394 660.744792369168 -77.3333333333333 37.5166666666667 -gcp 976.580225174465 1496.63921742496 -77.3166666666667 37.5 './dtpp/00347AD.png' './dtpp/VA-RIC-00347AD-PDF-AIRPORT-DIAGRAM.vrt'<br>
<br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDRzdVZDQzY2lZT1U/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDRzdVZDQzY2lZT1U/edit?usp=sharing</a><br><br>3d. gdalwarp the intermediate VRT to the final VRT <br>
gdalwarp -q -of VRT -t_srs EPSG:4326 -order 1 -overwrite ''./dtpp/VA-RIC-00347AD-PDF-AIRPORT-DIAGRAM.vrt'' './dtpp/warpedVA-RIC-00347AD.PDF-AIRPORT DIAGRAM.vrt'<br><br> <a href="https://drive.google.com/file/d/0B4EbUsrclSoDRGptZFhhaVdaT1E/edit?usp=sharing">https://drive.google.com/file/d/0B4EbUsrclSoDRGptZFhhaVdaT1E/edit?usp=sharing</a><br>
</div></div></div>