Distributed Recording
Contents
Introduction
Distributed Recording is a feature of iPi Recorder with the aid of which one can record synchronized video from multiple devices part of which are connected to one computer and others are connected to different computer(s).
This feature allows to overcome the following restrictions and limitations:
- Only single MS Kinect 2 sensor is supported by drivers and libraries from MS (so called MS Kinect SDK 2.0)
- This why multiple computers are required to record from multiple MS Kinect 2 sensors. And Distributed Recording allows to obtain one synchronized video in this case.
- Each MS Kinect 1 / ASUS Xtion / PrimeSense depth sensor should be connected to separate USB controller
- That is to record from two such depth sensors at least two USB controllers are required. From three depth sensors — three USB controllers. Most of laptops and even desktop PC don't have three USB controllers. But using Distributed Recording one can plug part of sensors to one computer and other part to other computer or even computers.
- Not more than two Sony PS3 Eye cameras can be connected to one and the same USB controller
- As a result to record from six PS3 Eye cameras three USB controllers are required; to record from eight PS3 Eye cameras four USB controllers are required; etc. And now there is an option: add controllers to one PC or use several computers to record.
- To record from large amount of cameras fast CPU and HDD are required
- Even if one have enough USB controllers to record using one PC, all data from all cameras should be processed and stored on disk drive in real time. This why we recommend to use modern 4+ cores CPUs and fast disk drives like SSD or/and RAID 0. But Distributed Recording allows to record even on low-end laptops distributing overall load on multiple not power enough computes.
Preparations
- Prepare as many computers as you need to record from all desirable devices (cameras, sensors, controllers).
- Install iPi Recorder on each computer.
- All computers should be connected to one and the same local network (LAN). In most cases it's most convenient to use Wi-Fi router for it.
- Note: You can use modern smart phone to provide Wi-Fi access point.
- Note: Internet connection is not required for Distributed Recording.
- For each computer:
- Attach all needed devices to each computer.
- Run iPi Recorder
- Prepare for recording as usual including devices selection, devices setup, background evaluation
- Now you should be on tab RECORD on each computer
Recording
- One computer will control other(s). This computer is called Master. Other(s) — Slave(s).
- You can choose any computer as master. On other computer(s) click Enter Slave Mode button. After that these iPi Recorders are slaves and will be controlled from master iPi Recorder as soon as it will be connected to them.
- On master computer click Connect to Slaves button. In the dialog Select Slaves for Distributed Recording you should see all your slave computers. Choose all required items and click OK.
- At the bottom of iPi Recorder window you'll see bar with information about connected slaves.
- Now you can start and stop recording on master computer as usual. In this case recording will be synchronously started and stopped on all computers involved in Distributed Recording.
- During recording each computer records to its own iPiVideo file on its own disk drive to the folder specified in the field Path on RECORD tab. File names will be as follows:
- name-master.iPiVideo — on master computer
- name-slave0.iPiVideo — on the first slave computer
- name-slave1.iPiVideo — on the second slave computer
- etc.
Merging
All iPiVideo files produced during Distributed Recording should be collected on one computer and merged to one resulted iPiVideo file which will include data from all cameras, sensors, controllers. Exactly this resulted iPiVideo file should be processed in iPi Mocap Studio to obtain animation.
Master iPi Recorder automatically starts downloading of iPiVideo file from all slaves. And after successful downloading of all parts performs merging to one resulted file.
Also you can perform manual merging. This can be helpful in the following cases:
- Automatic downloading is too slow and you prefer to use external HDD or something like to collect all iPiVideo files in one place.
- Automatic downloading is crashed.
To perform manual merging just click Merge Videos button on home screen of iPi Recorder, select all iPiVideo files produced by one Distributed Recording session and click MERGE button.