# processing with GCPs

**URL:** <https://community.pix4d.com/t/processing-with-gcps/6014>\
**Category:** PIX4Dmapper Questions/Troubleshooting\
**Created:** [February 22, 2018, 1:42am UTC](https://community.pix4d.com/t/processing-with-gcps/6014 "2018-02-22T01:42:14Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![James\_Smith](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@James\_Smith](https://community.pix4d.com/u/James_Smith)\
**Post date:** [February 22, 2018, 1:42am UTC](https://community.pix4d.com/t/processing-with-gcps/6014/1 "2018-02-22T01:42:14Z")

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&nbsp;I know how to include GCPs that I have chosen from the raycloud.&nbsp; I want to also include GCPs by just including their 3d coordinates.&nbsp; I can’t identify them specifically in the images.&nbsp; I ONLY have their coordinates.&nbsp; How can I do this?

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**Author:** ![Marili\_Giovani](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/marili_giovani/32/187_2.png) [@Marili\_Giovani](https://community.pix4d.com/u/Marili_Giovani)\
**Post date:** [February 22, 2018, 1:40pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/2 "2018-02-22T13:40:07Z")

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Hey James,&nbsp;

You can add GCPs from a file using the GCP/MTP manager.&nbsp;

Click **Import GCPs…** and add the file with their 3D coordinates. To take the GCPs into account, you should mark them on the images afterward and reoptimize.&nbsp;

You will find more info [here](https://support.pix4d.com/hc/en-us/articles/202560039-How-to-add-import-GCPs-in-the-GCP-MTP-Manager).&nbsp;

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<div class="post-metadata">

**Author:** ![James\_Smith](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@James\_Smith](https://community.pix4d.com/u/James_Smith)\
**Post date:** [February 22, 2018, 3:24pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/3 "2018-02-22T15:24:18Z")

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So, as I understand, I can not use GCPs unless I am able to locate them in my images?&nbsp;

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**Author:** ![Marili\_Giovani](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/marili_giovani/32/187_2.png) [@Marili\_Giovani](https://community.pix4d.com/u/Marili_Giovani)\
**Post date:** [February 22, 2018, 3:34pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/4 "2018-02-22T15:34:17Z")

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Exactly, you should mark your GCPs to be taken into account and georeference your project properly.&nbsp;

If you cannot mark the GCPs on the rayCloud, you can use the Basic Editor instead:[202560099](https://support.pix4d.com/hc/en-us/articles/202560099).&nbsp;

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<div class="post-metadata">

**Author:** ![James\_Smith](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@James\_Smith](https://community.pix4d.com/u/James_Smith)\
**Post date:** [February 22, 2018, 3:41pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/5 "2018-02-22T15:41:44Z")

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So, I can’t just mark 3 GCPs in the images and input the rest of the GCPs through the Basic Editor using their coordinates AND NOT have to mark them in the images?&nbsp; I don’t understand why the rest can’t be triangulated in place without marking them in the image.&nbsp; The other GCPs are in non-distinct places. I can’t recognize the placement in the images.

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<div class="post-metadata">

**Author:** ![James\_Smith](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@James\_Smith](https://community.pix4d.com/u/James_Smith)\
**Post date:** [February 22, 2018, 4:36pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/6 "2018-02-22T16:36:46Z")

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Alright Marili, I will assume that it is not possible.&nbsp; Thanks for your help.

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**Author:** ![Blaz](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/blaz/32/4344_2.png) [@Blaz](https://community.pix4d.com/u/Blaz)\
**Post date:** [February 23, 2018, 12:22pm UTC](https://community.pix4d.com/t/processing-with-gcps/6014/7 "2018-02-23T12:22:36Z")

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When importing the GCPs, marking some of them (minimum 3) and reoptimizing the project, the project&nbsp;is shifted&nbsp;to match the position&nbsp;of the marked GCPs. The&nbsp;GCPs that are not marked on the images will just appear in the project but will not be taken into account for georeferencing.

If you have issues to mark the GCPs in the rayCloud because of vertical shift, click&nbsp;[here](https://support.pix4d.com/hc/en-us/articles/206544136).&nbsp;

If you still encounter issues and you are referring to a specific project we recommend you to open a support ticket and we will have a look.

Best,

&nbsp;