Kolor Autopano Video Tutorial

The easiest way to stitch and create 360-degree immersive videos

Autopano Video is the new video-stitching software application for spherical videos developed by Kolor. It lets you assemble several videos into a single one covering up to 360 x 180 degrees. The user interface is designed to ease your workflow: drag and drop your source videos, choose a stitching template (including GoPro template) or launch a detection from scratch, use Autopano Pro or Giga to adjust your reference panoramas and click on Render.

Autopano Video Workflow and Tips

Note:

Autopano Video (AV) allows you to stitch the 6 videos from your Freedom360 rig into a fully spherical video. However, the software can be used to stitch fewer or more source videos. So AV is perfect for stitching 5 or 4 videos when you are using the Freedom360 with the 5X adapter.

Minimum requirement to achieve a good stitch:

• Use the same frame rate with all GoPro cameras.
• Use an audio signal (i.e. clap hands) at the beginning of the video.

Before opening Autopano Video:

• Shoot video: learn more about camera settings and how to connect and use the wifi remote in Tutorials.
• Prepare your videos for stitching:
  • Transfer files from the micro SD card to your hard drive.
  • Make sure there is one file per camera and name the videos i.e. cam1.mp4 , cam2.mp4. If there are several movie files please see Remark 1 below for more info.
  • Place all 6 (or 5) video files in the same folder.

   

The 360º video stitching workflow with Autopano Video (AV):

1. Open AV. Here is how the interface looks:
2. Load videos into AV using drag and drop.
3. Synchronization
   • Choose a point in time on the time axis (blue line in the center of the screen) for the automatic synchronization algorithm to start (i.e. beginning of the video where you used the audio signal)
   • Click on the “Synchronization” button under your source videos and the video synchronization tool pops up. 
   • Choose a search range i.e. 10s and start synchronization.
   • AV will indicate if the result is reliable or not. If it says the synchronization is precise move on to Step 3. If not (i.e. a difference of 15s) try to increase the sample size to up to 30s or choose a different point in time in the video.
   • Note 1: Take your time with this step! You really want to get this right!
   • Note 2: In certain cases, the algorithm may question the result even though the synchronization may be perfectly fine.
4. Create a reference panorama
   • Choose a point in the video on the timeline that represents the video as a whole. Avoid moments when objects are very close to the camera such as doorways.
   • Click on “Stitch as Gopro” button.
   • The reference panorama is created and appears on the bottom of the screen and, if selected,  in the preview window. If you are satisfied with the result go on to the next step. If not, create another reference panorama.
5. Edit the reference panorama
   • Select the reference panorama that you would like to use as template and click on the “Edit” button below the reference panorama or simply double-click the reference panorama of your choice. Autopano Pro/Giga (which ever you have purchased) will open with the reference panorama in the panoramas window on the right.
   • Click on “Edit” to open the Panorama Editor Interface.
   • Here is the toolbar of the Panorama Editor Interface with the most important tools that you will definitely or most definitely need. Description follows in the next steps.
   • Level the horizon: Click on the “Move Tool”. On the panel on the left side choose the pano move tool, click and hold on your panorama and pull up/down until the horizon is level. Save your progress.
   • Control Points Editor: Control points are automatically created. The GoPro cameras in the Freedom360 to have more than enough overlap. However, if there is not enough structure in the environment you might need to correct or add control points to optimize the stitch. For detailed explanation of the different functions please visit Kolor’s Autopano Giga documentation page.
   • Color corrections: Click on “Edit Color Anchors” and use the automatic color correction. For more control click on “Levels” and change the individual RGB channels and gammas. Don’t forget to click on the green check mark and save your progress.
   • Vertical lines: Click on “Verticals”. This tool lets you straighten a panorama by tracing vertical lines in the panorama’s editing area. Trace the lines from top to bottom (click and hold). Set at least 3 lines. Click on the green check mark and save your progress.
   • After you saved your changes, return to Autopano Video. The preview window is updated in real time.
6. Render the video
   • Click on the “Render” button below the preview window and the Render Settings video pops up.
   • Choose your encoding rules: i.e H.264 High will result in a 2k resolution, H.264 4k gives you the maximum resolution for Mp4 (limit of H.264).
   • Choose a name for your output file.
   • Click on “Panorama” and choose “Smooth” or “Sharp Mask” depending on the content of your video.
   • Click “OK” and the video starts to render.
   • Note 1: If you shot the videos with GoPro Hero black cameras your maximum achievable resolution with the six camera setup is ~5.6k. To get this resolution for your final output file choose to render as image sequence by selecting “Frames”. Then on “Panorama” choose the size (maximum is already set, no upscaling possible), choose the quality of the jpegs and click “OK”. This also requires to re-encode the frames with a different video editing program.
   • Note 2: You can render as both, Mp4 and Frames, at the same time but it will slow down the process.
   • Note 3: Always render your master file (i.e. image sequence) with the highest resolution possible and scale it to a particular publishing option later.
   • Note 4: The maximum resolution for iPad is 1920 x 960. This is smaller than 2k. 2k corresponds to 2048 x 1024.
   • Note 5: Rendering/stitching times vary. They depend on your GPU and CPU.

For additional support visit Kolor’s documentation pages: Autopano Video (Pro) tutorial, Autopano Pro tutorial and Autopano Giga tutorial

Remark 1: More than 1 file per camera for one continuous shoot.

In video mode, GoPro cameras have a file size limit of ~4GB. This means: If you are shooting with a GoPro Hero 3 black edition with a resolution of 1440p, a frame rate of 48fps and protunes ON the 4GB translate to about 15 minutes of footage. If you are shooting longer than that, the camera will start a new file until it reaches 4GB and start another file.
Before you start a stitch with AV, you should concatenate the video files, i.e create one continuous file, from each camera. You can find the instructions how to do it here: http://www.autopano.net/wiki-en/action/view/Autopano_Video_-_Concatenate_several_mp4

Remark 2: About synchronization

The quality of the video stitch depends heavily on the ability to synchronize the source videos up to the same frame. For that reason, Kolor introduced audio synchronization to optimize the process.

Even though, starting the GoPro cameras with the Wifi remote does not ensure that each camera starts  recording at the precise same moment. For example, if shooting at 24fps one camera to the next can have a frame offset (the time when the particular frame is recorded) of almost 40ms. If there is fast movement in the video this is very noticeable. Therefore, it is recommended to shoot at higher fps for a better synchronization. The faster the movement that you are shooting the higher the fps! Shooting at 48fps the frame offset is down to 20ms and shooting at 100fps (if possible) it is down to 10ms.