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====== Resources for Online Teaching (for MAC users)====== Please feel free to add/edit by creating a wiki login (register<- link at the top right of this page). [[windows|Link to a similar Windows page]] [[Linux|Link to a similar Linux page]] ===== External camera as a Webcam for your computer/laptop===== Since the laptop camera is usually low resolution and inconveniently located, it might be convenient to use an external camera ==== DSLR ==== It is possible to use a DSLR as an external webcam though in many cases the length of the recording is limited by hardware. However point and shoot cameras usually do not support this function. Two methods: - Software capture using USB - automatic detection for some cameras supporting live view (not tested yet) - paid softwares (that I am aware of): [[https://sparkosoft.com/sparkocam|Sparkocam]], [[https://manycam.com|Manycam]], [[https://www.ecamm.com/mac/ecammlive/|Ecammlive]]: just attach the camera USB to the laptop and video recording or streaming should be possible. Works only for a list of cameras supported by these softwares (list maintained on the respective software websites) - Free software: none that I could find for Mac (in windows [[https://www.usa.canon.com/internet/portal/us/home/support/self-help-center/eos-webcam-utility/|Canon EOS webcam utility]] for Canon DSLRs. Does not work for other brands.) - Hardware capture through capture card(HDMI to USB): - [[https://www.elgato.com/en|Elgato Camlink]] (expensive) - Other cheaper cards..but not sure about usability ==== Smartphone ==== It is possible to use almost every smartphone as an external webcam either over wifi or over USB. A client app runs on the phone and a server version runs on the host computer. Though there are many apps available that enable this feature, the free versions leave an advertisement showing somewhere in the video. - [[https://iriun.com|Iriuncam]] (best one since the logo showing on the video is the smallest) - [[https://www.kinoni.com|Epoccam]] - [[https://www.dev47apps.com|Droidcam]] - Others ===== External Camera live view on PC/Laptop (but not as a webcam) ===== Several options available for tethering your DSLR to your computer. The video from the DSLR is visible live in an app on the computer screen. This can be shared with others through any screen sharing app e.g. Zoom/Webex etc or recorded through a screen recording app. A list of such softwares is maintained [[https://www.tethertools.com/tethering-software/|here]]. Some of them might also support live streaming to YouTube etc. ===== Audio to computer ===== * This is easy with any number of bluetooth/wifi/wired headsets with microphones. Reasonably priced ones are available with long (20ft wires). * If you have no microphone available, then it is possible to convert your smartphone into a wireless/USB/bluetooth microphone for your Mac with various apps: (e.g. [[https://wolicheng.com/womic/|WO mic]]) ===== Video Recording/Streaming ===== * Recording: Quicktime does a good job, with video from external webcams/phones and audio from external wifi/wired microphones. This might be useful if a live lecture on a whiteboard needs to be recorded. One might require VLC to compress/convert to other formats. * Streaming: OBS (see below) can be used, or audio/video can be directly fed into Zoom/Webex etc. (See trouble shooting below, if your phone webcam does not show up on zoom/webex options). ===== Screen Recording with Audio ===== * Quicktime can record screens efficiently with voice over. Composite videos can be directly created by having video from a webcam/tethered camera on half the screen and ppt/digital whiteboard on the other half, and then recording the full screen. * PPT with Audio (many options, possible with OBS (see below) also) * iPad screen recording (native option in iOS, also possible with OBS(see below). OBS advantages include switching online between teacher video and the iPad screen while streaming) ===== Video/Audio Mixing ===== This is required to, e.g., superimpose/switching between slides with video/audio of the lecturing teacher, superimposing/switching between teacher's video/audio with writing on the iPad, superimposing/switching between video/audio of writing on a board with slides, cleaning noise on audio etc. - The best free/open source resource is OBS Studio ([[https://obsproject.com|Open Broadcaster Software Studio]]): - This one can combine different video and audio sources and record the composite video. - It can also output to a streaming service like YouTube if live streaming of lectures are desired. - It can also output to a Virtual webcam through a [[https://github.com/johnboiles/obs-mac-virtualcam|OBS Virtual webcam plugin]], so that video conferencing software such as Zoom/Skype/Webex/Google meet can use this stream. - The other option is to use any screen recording+/sharing app (e.g. Quicktime or Zoom) for video mixing. Various apps can be displayed together on the screen and the composite screen can be recorded. E.g. the video from a tethered camera can be displayed on half the computer screen and a ppt can be displayed on the other half. Then zoom can be used to share and simultaneously record the entire screen with a VoiceOver. Caution: OBS can look a little intimidating, but we need only few of the features which can be learnt very quickly through many available YouTube tutorials. ===== Video Editing ===== For recorded lectures, video created and recorded through OBS may be edited/compressed using iMovie available in Mac. OBS does not support video editing, however during recording, a lot of tricks (e.g. fading, switching video feeds) are possible in OBS itself. ===== Video Compression ===== * The best option is [[https://handbrake.fr|Handbrake]]. It provides various codec options with adjustable quality and resulting file size. As a benchmark: A one hour iPad whiteboard video/audio lecture should be legible at a file size of 100-150MB. * VLC also can be used, though not as good as Handbrake. ===== Trouble Shooting ===== - Phones have good cameras, but the phone battery drains quickly using it as a webcam. USB connection to the computer resolves this issue but might require "enable developer options" enabled on android phones. - Some of the recent versions of Skype/Zoom/Meet etc might have disabled the option for the program to recognise virtual webcams e.g. the OBS virtual webcam. In that case when the video configuration options on any one of these programs(say Zoom) is opened, we see only the laptop webcam and not the virtual webcams.The fix is to run this line of instruction at the command prompt in terminal (for Zoom, similar line for other apps) : ''codesign --remove-signature /Applications/zoom.us.app/'' ===== Links to online material created by our faculty ===== - EE204: http://www.ee.iitb.ac.in/~zelerajesh/index.php/teaching-2-2-4-2-4-2-3-2/ - EE720: https://www.youtube.com/playlist?list=PLdSfOtW8hZbO4CupfBN7ghE5ourNwUlA7 - EE324: https://youtu.be/_wKIS5RoZeA and https://youtu.be/swwxjdQ9DGU - EE636: https://www.ee.iitb.ac.in/~debasattam/ee636.html

start.txt · Last modified: 2020/07/06 18:18 by Debraj Chakraborty