# Capturing Photos

When surveying, you might want to take a photo from your camera or attach an existing photo from the device gallery to your survey feature.

Here, you will find the overview of the basic functionality related to capturing photos, such as:

TIP

Do you need to attach multiple pictures to one feature? How to attach multiple photos to features will guide you through the setup.

WARNING

Keep in mind that synchronising photos during the field survey can use up a lot of mobile data - depending on the amount of pictures taken and their size.

To reduce the data usage, you may consider using selective synchronisation, resizing pictures automatically or following the offline field survey workflow.

# Attachment widget in QGIS

TIP

Clone Mergin Maps Project documentation/form_setup documentation/form_setup (opens new window) to follow this example!

To set up a photo widget:

  1. Right-click on a layer, select Properties and go to the Attributes form tab.
  2. In the list of Available Widgets select the text field you want to work with.
  3. In the Widget Display tab:
    • From the drop-down menu, select Attachment
    • Default path defines where images will be saved. If it is not defined, the project home folder will be used.
    • Store the path as Relative to project path or Relative to default path depending on how you want to store the paths.
  4. Apply the changes. Don't forget to save and sync your project!
    QGIS photo attachment widget form

Here is an overview of paths that will be stored in various settings of the attachment widget. path/to/project represents the project home folder, where the project file is located.

Default path Store path as Value
- Absolute Path <path/to/project>/image.jpg
- Relative to project path image.jpg
- Relative to default path image.jpg
@project_folder Absolute Path <path/to/project>/image.jpg
@project_folder Relative to project path image.jpg
@project_folder Relative to default path image.jpg
@project_home + '/photos' Absolute Path <path/to/project>/photos/image.jpg
@project_home + '/photos' Relative to project path /photos/image.jpg
@project_home + '/photos' Relative to default path image.jpg

# How to set up a custom folder for storing photos

It can be useful to set up a custom folder for photos, e.g. if you want to use selective synchronisation or if you simply want to have your data organised.

To set up a custom folder:

  1. Create a subfolder in the project folder (here: photos)

  2. Open your project in QGIS

  3. Open the Properties of the survey layer and navigate to the Attributes form tab.
    Select the field, where photos are stored (here: photo) and make sure that the widget type is set to Attachment:
    QGIS photo attachment widget form

  4. Now we need to change the Default path to the folder we have created. Click on the Data defined override icon and choose Edit...
    QGIS edit default path expression

  5. In Expression String Builder enter the expression @project_folder + '/photos' (replace photos by the name of your folder). Click OK.
    QGIS enter default path expression

  6. The Default path now refers to the custom folder.
    QGIS default path to custom folder

  7. Apply the changes. Don't forget to save and sync your project!

# Resizing pictures automatically

Photos that are captured during the field survey or uploaded using Mergin Maps mobile app can be automatically resized, e.g. to save up storage space. The quality of the photos can be set up in the Mergin Maps project properties using Mergin Maps QGIS plugin.

# Customising photo name format with expressions

Photos taken in the field using Mergin Maps mobile app can be automatically renamed. This can be useful when browsing pictures in your Mergin Maps project and keeping them organised.

TIP

How to Set Photo Names Format will guide you through the setup and provide examples of expressions that can be used to name your photos.

# Photos in Mergin Maps mobile app

Using the photo widget in Mergin Maps mobile app, you will have two options:

  • Take a photo to use your camera app for taking a photos
  • Add from gallery to attach an existing photo from your device.

Mergin Maps mobile app photo widget

# Displaying photos in QGIS

Photos taken using Mergin Maps mobile app during the survey can be displayed in the feature's form in QGIS.

  1. In QGIS, double click on a survey layer to open Layer Properties

  2. In the Attributes Form tab, select the field that contains the path to the photo.

    Scroll to the Integrated Document Viewer in the panel on the right. Set the Type to Image.
    QGIS Integrated Document Viewer

  3. Apply the changes and click OK.

Now when you click on a feature that contains a photo, it will be displayed in the form.

Mergin Maps mobile app photo displayed in form