How to convert a Voluson 4D ultrasound scan (.V00 file) to a video?

Solution 1:

.V00 files are the "Kretzfile" / "Kretz 3D Ultrasound Images" format [source]. The connection between GE Healthcare and Kretz is because "In 2001, GE Medical Systems acquired a major shareholding in Kretztechnik AG from Medison, and Kretztechnik AG became a wholly owned subsidiary of GE Medical Systems" [source].

You can use 4D View. This is the "official" PC software provided by GE Healthcare for their Voluson ultrasound imaging machines. Example process on how to export to a video with it:

1. Open the file in 4D View and choose "File → Export 4D Img. Cine Sequence…".
2. Tick the option "Compression" (except if you want postprocessing in step 4, don't use compression to prevent a bug). Leave "Reduction Ratio" at "1.00 : 1", as else it would downscale the video resolution.
3. Click "Save" to export the 4D volume to .avi format. What you get should look like a replay in 4D View, just without all the lettering.

4. To remove the huge black borders from the video, to connect multiple exported videos and to convert it all into a small MP4 format, you can run the following ffmpeg command in a Linux shell, while in a directory that contains your exported, uncompressed .avi files and nothing else:

   ffmpeg \
     -i concat:"$(ls -l *.avi | awk 'BEGIN {ORS="|"} { print $9 }')" \
     -filter:v "crop=400:380:332:175" \
     -r 25 \
     -crf 18 \
     output.mp4
   

   This is based on several other answers. If you have avconv instead, it works with the same parameters. It assumes 400×380 px content starting at x=332, y=175 (that is, about centered on a 1068×740 px video) – adapt the crop= parameter values to your case if needed by measuring on a stillframe. -crf 18 selects a higher quality than the default -crf 23, at the expense of bigger file size. I doubt if the quality improvement is visible though …

5. For archiving purposes, you might want to store the individual AVI videos (huge if uncompressed!) in a nice lossless or near-lossless format, without concatenating them, but again removing the useless black border:

   for file in *.avi; do
     ffmpeg \
       -i $file \
       -c:v libx264 \
       -preset veryslow \
       -crf 1 \
       -r 25 \
       -filter:v "crop=400:380:332:175" \
       ${file/.avi/.mp4};
   done
   

   This uses H.264 with quantizer value 1 (-crf 1), which is very near lossless [source] and 25 times smaller than the original uncompressed AVIs. You can also use -crf 0 or better -qp 0 instead, which will result in truly lossless H.264. It is about 20% larger, and not all players can read it [details]. But VLC and YouTube can, for example.

Some hints on obtaining and installing 4D View:

• 4D View is available as licenced software, a 60-day unrestricted demo version, and a non-expiring de-featured version [see]. All seem capable of exporting to .avi files, but I did only try with the 60-day demo.
• The newer versions of 4D View can only be downloaded by registered owners of Voluson machines (you need to sign up and give your machine's serial number; but maybe they will make an exception if you ask kindly). Earlier versions were publicly downloadable however, and are still available on the web.
• 4D View is made for Windows 7, but can also be installed in Windows XP etc..
• 4D View can not be used in a virtual machine, at least not in VirtualBox with Windows XP guest (and 3D acceleration enabled). When trying to start it, 4D View will complain "No sufficient graphic card found or driver not installed" and exit.

Some more details and contacts around converting V00 files can be found in this comp.protocols.dicom thread. For background info, there is also the Voluson S6 / S8 Service Manual. For tests, here is a hard-to-find 3D scan in Kretzfile format for download; just 3D though, so not allowing the 4D-to-.avi conversion with 4D View.

Not possible: 4DTheFetusView. This tool is the same as a 2005 version of 4D View and still available for free download. Except, it can only be used to open demo volumes shared via sonoworld.com. These 4D demo volumes had been attached to several of their cases (incl. this, this, this) but are no longer available for download.

Not possible: DICOMatic. This is a freely downloadable conversion tool that can convert a multitude of proprietary medical imaging formats to the new standard format DICOM. Just that an unregistered version watermarks exported images [source]. From DICOM, one could proceed with the freely available tools MicroDICOM or DICOM Cine Viewer to export a video file. However, for the GE KretzFile format, DICOMatic notes that "DICOM do[es] not support 3D volumes for ultrasound images" [source]. When trying to open a .V00 file in DICOMatic, I got the note that it does not support polar coordinates. Probably that's equivalent to saying that 3D volumes are not supported (?). So, it did not work (for me), but the manufacturer says that it should work [source].

Not possible: TomoVision and a screengrabber. TomoVision is a viewer for medical image formats, so if it could render .V00 sequences, one could convert it to a video with a screengrabber. However, since it uses the same library as DICOMatic [source], it will also be unable to read the 4D volume. Though again, the manufacturer claims it should be possible [source].

Solution 2:

I've implemented a GE/Kretz 3D ultrasound image reader in 3D Slicer. After you have loaded the image you can use all the awesome tools in 3D Slicer to visualize and process it (for example, to create a 3D-printable model). You can see a demo here:

https://youtu.be/UHq0uyDvhaA

It's not perfect yet (spherical to Cartesian conversion is not fully accurate), but it's completely free and open-source - fixes and improvements are welcome. For further details and questions please post to the 3D Slicer forum:

https://discourse.slicer.org/t/loading-of-ge-kretz-ultrasound-volumes-vol-file/808/14?u=lassoan