What is the best way to record the mac screen with cocoa? I know there are many examples at the apple developer reference library. SonOfGrab explain how to capture the screen with quartz but also that it isn't enough fast to use it to grab many frames every second. OpenGLScreenSnapshot has same results but it isn't fast, too. OpenGLScreenCapture seems to be the best way to do it but XCode prompts me many errors because it's made for 10.4 and it requires old Quicktime commands I think they pushed into QTKit but I can't find a way to convert it. Could anyone send me to someone's site that converted the project or tell me if there are some other ways to do it. Thanks in advance.
OpenGL would be the way to go. You should still be able to use the OpenGLScreenCapture sample if your architecture is set to 32-bit. (QuickTime is not available in 64-bit.)
-Ken
Related
I've got a big ask here, but I am hoping someone might be able to help me. If there's another site you think this should be posted on, please let me know.
I'm the developer of the free app Amphetamine for macOS and I'm hoping to add a new feature to the app - keeping a Mac awake while in closed-display (clamshell) mode while not having a keyboard/mouse/power adapter/display connected to the Mac. I get requests to add this feature on an almost daily basis.
I've been working on a solution (and it's mostly ready) which uses a non-App Store helper app that must be download and installed separately. I could still go with that solution, but I want to explore one more option before pushing the separate app solution out to the world.
An Amphetamine user tipped me off that another app, AntiSleep can keep a Mac awake while in closed-display mode, while not meeting Apple's requirements. I've tested this claim, and it's true. After doing a bit of digging into how AntiSleep might be accomplishing this, I've come up with 2 possible theories so far (though there may be more to it):
In addition to the standard power assertion types, it looks like AntiSleep is using (a) private framework(s) to apply non-standard power assertions. The following non-standard power assertion types are active when AntiSleep is keeping a Mac awake: DenySystemSleep, UserIsActive, RequiresDisplayAudio, & InternalPreventDisplaySleep. I haven't been able to find much information on these power assertion types beyond what appears in IOPMLibPrivate.h. I'm not familiar at all with using private frameworks, but I assume I could theoretically add the IOPMLibPrivate header file to a project and then create these power assertion types. I understand that would likely result in an App Store review rejection for Amphetamine, of course. What about non-App Store apps? Would Apple notarize an app using this? Beyond that, could someone help me confirm that the only way to apply these non-standard power assertions is to use a private framework?
I suspect that AntiSleep may also be creating a virtual keyboard and mouse. Certainly, the idea of creating a virtual keyboard and mouse to get around Apple's requirement of having a keyboard and mouse connected to the Mac when using closed-display mode is an intriguing idea. After doing some searching, I found foohid. However, I ran into all kinds of errors trying to add and use the foohid files in a test project. Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app? I'm not asking for code help with that (yet). I'd just like some help determining whether it might be possible to do.
Thank you in advance for taking a look.
Would Apple notarize an app using this?
I haven't seen any issues with notarising code that uses private APIs. Currently, Apple only seems to use notarisation for scanning for inclusion of known malware.
Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app?
Taking a quick glance at the code of that project, it's clear it implements a kernel extension (kext). Those are not allowed on the App Store.
However, since macOS 10.15 Catalina, there's a new way to write HID drivers, using DriverKit. The idea is that the APIs are very similar to the kernel APIs, although I suspect it'll be a rewrite of the kext as a DriverKit driver, rather than a simple port.
DriverKit drivers are permitted to be included in App Store apps.
I don't know if a DriverKit based HID driver will solve your specific power management issue.
If you go with a DriverKit solution, this will only work on 10.15+.
I suspect that AntiSleep may also be creating a virtual keyboard and mouse.
I haven't looked at AntiSleep, but I do know that in addition to writing an outright HID driver, it's possible to generate HID events using user space APIs such as IOHIDPostEvent(). I don't know if those are allowed on the App Store, but as far as I'm aware, IOKitLib is generally fine.
It's possible you might be able to implement your virtual input device using those.
We're in process of developing a desktop application which needs to record user's screen once he clicks a button. I read a tutorial about Adobe AIR, which says it is easy to do with AIR: http://www.adobe.com/devnet/air/flex/articles/air_screenrecording.html
But our preference is Titanium as we've explored it a little bit. So I want to know is that even possible? If yes, how can we get started with?
There's also an interesting solution which uses Java applet for recording, as demonstrated here: http://www.screencast-o-matic.com/create?step=info&sid=default&itype=choose
But again, we're not sure about JAVA and would like to know how can it be done? or if its even possible to run a JAVA applet in Titanium?
When you say "record screen", I'm assuming you mean video. Correct?
The only way to do this in Titanium Desktop right now is to take a bunch of screenshots and string them together (encoding would probably need to be done server-side).
Depending on how long your videos need to be, this probably won't work for you. I'm also not confident in how quickly you could capture screenshots, and if it would have a high enough frame rate to be usable.
Past that, a module could be developed for Desktop to support some native APIs to record video. That's not something I see on the horizon, though.
I hope this helps, albiet a rather dismal answer. -Dawson
I am working on one application where i need to display notification for the devices in the bluetooth range. I surfed a lot also searched in the stack overflow,but got most of the questions unanswered or the solution to use pacifist,which is quite impossible for me,as i cant download old version of xcode,its not allowed in my organization.
So can anybody help me out with some sort of example code or something that i can use in my application and proceed further?
Thanking you.
-Sarah.
Is this for the Mac or for iOS? If it's the latter, I'm sorry to report that after having researched the heck out of it, there's no App-Store-safe way to access the Bluetooth stack. That leaves no way to detect nearby devices except through Gamekit, which is very limited.
[Edit: note that this is old information, and that much more is available now.]
Try Bonjour for zero-configuration networking/detection between devices. It silently switches between Bluetooth and WiFi but it may still suit your needs.
As part of test automation framework building, I need to record the activities done by the user in a video.
Since i could not find a way to record a video directly in vb, i opted to capture a sequence of screen shots (print screens) and then convert it to a streaming video.
Please suggest a way to do the same.
thanks,
pkrg
maybe you can just run another program behind your application.
there are several programs like that.
it is not a professional way but easy way to do this... because probably these programs have already optimized their algorithms...
making avi with jpegs:
there are such a programs that do this too...
again you can search for it..
You can automate Windows Media Encoder there are some samples for C# and VB.NET in the SDK
I would recommend you to use CamStudio to record user activities of your program. It is also open-source.
if you want to roll your own, then
http://support.microsoft.com/?kbid=161299
Shows several ways to call windows api, to caputure the screen or parts of. Still I think you will have problems with the mouse cursor though. After capturing the screen you will have to draw the cursor in the correct position.
Is it possible to access the iSight camera on a macbook programmatically? By this I mean I would like to be able to just grab still frames from the iSight camera on command and then do something with them. If so, is it only accessible using objective c, or could other languages be used as well?
You should check out the QTKit Capture documentation.
On Leopard, you can get at all of it over the RubyCocoa bridge:
require 'osx/cocoa'
OSX.require_framework("/System/Library/Frameworks/QTKit.framework")
OSX::QTCaptureDevice.inputDevices.each do |device|
puts device.localizedDisplayName
end
I don't have a Mac here, but there is some Documentation up here:
http://developer.apple.com/documentation/Hardware/Conceptual/iSightProgGuide/01introduction/chapter_1_section_1.html
It looks like you have to go through the QuickTime API. There is supposed to be a Sample Project called "MungGrab" which could be worth a look according to this thread.
If you poke around Apple's mailing lists you can find some code to do it in Java as well. Here's a simple example suitable for capturing individual frames, and here's a more complicated one that's fast enough to display live video.
There's a command line utility called isightcapture that does more or less what you want to do. You could probably get the code from the developer (his e-mail address is in the readme you get when you download the utility).
One thing that hasn't been mentioned so far is the IKPictureTaker, which is part of Image Kit. This will come up with the standard OS provided panel to take pictures though, with all the possible filter functionality etc. included. I'm not sure if that's what you want.
I suppose you can use it from other languages as well, considering there are things like cocoa bridges but I have no experience with them.
Googling also came up with another question on stackoverflow that seems to address this issue.
Aside from ObjC, you can use the PyObjC or RubyCocoa bindings to access it also. If you're not picky about which language, I'd say use Ruby, as PyObjC is horribly badly documented (even the official Apple page on it refers to the old version, not the one that came with OS X Leopard)
Quartz Composer is probably the easiest way to access it, and .quartz files can be embed in applications pretty easily (and the data piped out to ObjC or such)
Also, I suppose there should be an example or two of this in the /Developer/Examples/
From a related question which specifically asked the solution to be pythonic, you should give a try to motmot's camiface library from Andrew Straw. It also works with firewire cameras, but it works also with the isight, which is what you are looking for.
From the tutorial:
import motmot.cam_iface.cam_iface_ctypes as cam_iface
import numpy as np
mode_num = 0
device_num = 0
num_buffers = 32
cam = cam_iface.Camera(device_num,num_buffers,mode_num)
cam.start_camera()
frame = np.asarray(cam.grab_next_frame_blocking())
print 'grabbed frame with shape %s'%(frame.shape,)