Opening Raw Images in ArenaView MP

Introduction

ArenaView MP (AVMP) lets you save images in common image formats such as PNG, JPG, and TIFF. You can also save images in raw image format; because raw images contain the pixel values for the image, AVMP will create an accompanying JSON file that contains details for the raw file. When you open a raw file in AVMP, it needs both the raw image file and the accompanying JSON file.

Setting the working directory

Before you can save an image, you will be prompted to set the working directory in ArenaView MP. Do the following:

From the menu bar, select Controls > AVMP.
In the pane that opens, click on the green folder symbol.
Choose a directory for the folder of saved images.

Images will then be saved in the folder in the working directory you have chosen.

Saving images

To save an image in a specific format, follow these steps:

Start streaming or press the snap button to get an image.
Do either of the following:
- From the menu bar, select File > Save As.
- In the window with the image/stream, right-click on the image and select Save As.
This opens the following file dialog. In the dropdown, pick the format to save the image as.

When saving a QOI capture as a raw image, it will save as its non-compressed equivalent. For example, if you save a QOI_Mono8 raw image, it will save a Mono8 raw image instead.

Additional options

There are several more settings and controls available under Controls > Save & Load > Save Image. For most of these settings, you need to stream from a camera or have a window open with an image from the camera.

File name pattern

You can adjust the file pattern used for savings images:

For more syntax help, click on the question mark character shown in the UI above.

File format settings

Additionally, for different image formats you can adjust settings related to compression, quality, and subsampling.

File Format: Available file formats are TIFF, PNG, JPEG, RAW, and BMP.
Format-specific settings that appear include JPEG subsampling and compression settings for TIFF and PNG.
Save Raw Data Only: This forces raw image into JPEG, PNG, BMP, and TIFF files, and can result in corruption.

The file format settings that are configured here are applied to all quick actions (i.e., when using ‘Save’ instead of ‘Save As’ or clicking the pink floppy symbol). There are several quick ways to save images by doing one of the following:

Clicking the pink floppy symbol .
From the menu bar, selecting File > Save.
In the window with the image/stream right-click on the image and click Save.

Opening images

To open an image, do the following:

From the top ribbon, select File > Open Raw.
Choose the desired image format.
Navigate to the file and double-click it.

If you are opening a raw image, it will open in ArenaView MP in a new window. Other images will be opened in your OS’s native image viewer.

Example

When you unzip open the example files below in AVMP, the raw data appears. You can control the pitch/yaw, the panning, and the distance from the focal point just like you would if you were streaming directly from the camera.

Example files for HTW003S-001

Example file opened in ArenaView MP. To obtain the view above, ensure that the settings Controls > Image Processing > Time-of-Flight Processing > Channel Selection is set to Intensity.

Raw images

The raw image file contains the image data as it was obtained from the camera. Not all of this information is preserved when the image is saved in a standard image format.

To open a raw image, you need the accompanying JSON file for it. AVMP creates the JSON file when you save the raw image. It has the same name as the raw image but with the .json extension appended to it. For example, if a raw image has the filename “TRI050S_image.raw” then the JSON file has the name “TRI050S_image.raw.json”. If ArenaView MP cannot find the JSON file, then an error will result.

Raw images that contain the following pixel formats cannot be opened:

All line scan CFA pixel formats
XYTPFrame
RawFrameEncoded

Attempting to open raw images with these pixel formats will fail and result in an error.

If you attempt to open a raw video in ArenaView MP, it will only show the first frame of the video. This is because raw videos are just raw images appended together. Playback of raw videos is not supported in ArenaView MP.

Recreating the JSON file

A raw image only contains the raw pixel data of the image, so the JSON file is needed to correctly view it. If you do not have the JSON file, then you can reconstruct it if you know the height, width, and pixel format used for the image.

For example, here is the JSON file for a raw image taken from a TRI050S:

{
    "height": 2048,
    "pixelformat": "Mono8",
    "width": 2448
}

This is the format used for all raw images. As mentioned in the previous section, the JSON file should have the exact same name as the raw image file, plus the .json file extension appended to it.

If you only know two of the specific values, then it may still be possible to reconstruct the JSON. For example, if you only know the values of the height and pixel format, you can perform some calculations to figure out the width:

File Size (bytes) = Width × Height × Pixel Format Size (bytes)

Understanding the pixel format makes things easier as many pixel formats take up the same size in bytes. The following articles describe the layout and size of different pixel formats: