Optimize Imagery

This page describes the desktop procedure “Optimize Imagery” for Aerial, Mobile, and Oblique Mapping.

1. Open Mapping Run, see Manage Mapping Runs
2. Procedures > Aerial / Mobile / Oblique Mapping > Optimize Imagery

Concepts

The procedure “Optimize Imagery” makes it possible to :

  • Optimize all Original Images of the Opened Run into Processed Images.
  • Create for each group of Planar Images of the Opened Run a single Spherical Reference Image.

Processed Image

Normalized Image

Optimize Imagery uses the OrbitImageOrientation values to optimize supported Original Images into Normalized Orbit OMI Processed Images.
An Orbit OMI Image is Orbit's native multi-resolution image storage format, see Orbit Multiresolution Image.
A normalized image is north-oriented and doesn't use the OrbitImageOrienationPan photo position attribute values.

Open Image

When opening an image from a Mapping Resource, the processed image will be used if available. If no processed image is available, the original image will be opened.
If a Processed Image is available, the Original Image is no longer used.

Optional for 3DM Desktop, Mandatory for 3DM Viewer

Processed Images are optional for all Orbit 3DM Desktop products but required for Orbit 3DM Viewer. In Desktop use of Processed Images is still recommended when loading uncompressed Original Images.

Processed Images reduce CPU requirement for Publisher Server and enable an efficient multi-resolution image transfer between Publisher Server and 3DM Viewer.

Jpg quality and Compression

However jpg quality can be set to apply compression, Processed Images are not optimized to reduce file size. If the same jpg quality is used for both Original and Processed Images, then the file size will increase by ~30%.

As Jpg Quality for Processed Images, we advise

  • Jpg quality Processed images = or < Jpg quality Orignal Image.
    It's worthless to set a target Jpg quality of the processed images higher than the source original images.
  • Jpg quality Processed image < 90.
    Jpg quality higher than 90 will increase the file size significantly with marginal quality gain.

Requirements

Requirements to optimize Original Images into Processed Images:

  • An Orbit Mapping Run of Version 2 or newer, see Orbit Mapping Resources - Structure and Configs.
  • Local file access to Original Images. Online Original Images cannot be used. Use of link.ini image reference file is supported.
  • Powerful CPU and 100% memory availability.
    For larger files, in sense of the number of pixels (the physical size on the disk and used compression factor don't influence memory requirements) the available memory allocated to Orbit might need to be increased, see Orbit Desktop Startup Configurations.

Spherical Reference Image

Advantages

A Spherical Reference Image combines the ease of use of Spherical Images and the accuracy of Planar Images.
One can easily navigate from one Planar Image Group to another nearby recording position and open one of the available high resolution and accurate Planar Images.

Requirements

Create Spherical Reference Image requires :

  • An Original Run of Version 3 or newer, see Orbit Mapping Resources - Structure and Configs.
  • Local file access to Original Images.
  • Planar Image Group Identifier for each recording position, stored in photo position “OrbitPhotoGroupId” attribute.
  • Import Template addon “panorama_planargroups”.
    Provide an Orbit Mapping Run to Orbit Support to receive the required template addon.

Procedure

Optimize

Optimize all Original Images of the Opened Run into Processed Images.

Quality

Set jpg compression quality for the processed images.

Select one of the preset values or use “Custom” to set any quality value via the slider below.
Higher quality will increase the file size and the corresponding time to load the image.
There is no point to process the images with a higher quality than the original image files. For most use cases jpg quality 75 “Good” will be ok.
More information about the effect of jpg quality and compression : https://en.wikipedia.org/wiki/JPEG.

Resolution

Set image size in pixels.

the software automatically detects the size of the original images.It is advised to keep the original settings, only if you have huge images(over 10000×5000)it is reasonable to downsize them. The ratio should always be kept as it is.

Mask

Optionally a mask file can be applied on top of the original images to hide unwanted structures e.g. GPS antenna while processing the optimized images.

It is possible to use a default mask provided by Orbit or to add a customized one. A mask must be created in .png format with the same resolution as the original images. The area which corresponds with the unwanted structures must be covered by a polygon filled with a solid color and transparent background on the remaining part of the image.

To create a custom mask, the Mask Creator can be used or directly placed into the folder:
…\AppData\Local\Orbit GT\Orbit [Product]\mobile_mapping\masks.

The images must be located in the original folder. After the Optimize Imagery procedure, the new .omi images will be stored in the newly created processed folder.

If not all the images are optimized after the end of the procedure, it might be necessary to run the process a second time.

Once a mask is chosen and the procedure has started, all the processed .omi files will contain the mask.

Optimize Imagery does not overwrite previously processed images, therefore the previously processed images that were created must be deleted.

Blur & Erase

Set the option to apply blurred and erased registered areas.

Optionally activate blurring to be applied on top of the processed images.
Blur and erase areas can be registered using the Orbit extension Blur and Erase extension, see Blur and Erase.

Process

Delegate job to Task Manager or start processing now.

CPU and Memory requirements
Optimize image process is multi-threaded and uses all available CPU and Memory resources. This process reduces your computer performance and affects/is affected by other running processes.
We strongly recommend isolating this process, for example running overnight, to avoid any CPU or memory issues.

Stop and Restart Processing
All images of the currently opened run will be processed.
This process can be interrupted at all time. Already Processed Images are retained and this job can be restarted to process remaining Original Images at all time.
To re-process already Processed Images the appropriated Processed Images need to be removed from the Orbit Run :
<Orbit Run>/<camera>/processed

Processing Time
Some stats and facts of processing images

Example image processing 123,787 images/ 59 hours 27 minutes, 2082 images/hour, 34.7 images/minute

  • 64bit, Quad-core, 16GB memory, Intel core i7
  • read from external USB3 connected hard disk
  • write to internal SSD drive
  • original images : 8000×4000 pixels, jpg quality 80, average size of 4.25 MB/image,
  • processed images : same resolution and quality, average size of 5.31 MB/image

Create

Create for each group of Planar Images of the Opened Run a single Spherical Reference Image.

If the above-described requirements are fulfilled the second procedure step “Create” will be added automatically.

Delegate job to Task Manager or start processing now.
At the moment do not cancel or interrupt the process.

 
Last modified:: 2022/07/29 07:53