Record Videos with videoGrabber are too big

[Nana]

We record videos on Windows/Mac with this method:
http://revolution.byu.edu/video/videoGrabber.php

the videos are too big.

is there a way to record smaller videos?

[Martin Koob]

revVideoGrabber is likely capturing at the Camera's native quality.

When the user opens the revVideoGrabber dialog the can adjust the compression settings in the compression tab. Here they can pick the compression type. I would suggest picking .H264. They can also adjust the quality. I would suggest medium. They can also adjust the frame rate and limit the data rate. I don't touch these.

Unfortunately you can't script the video capture settings with revVideoGrabber you have to leave it up to the user to select them so you have to include documentation for the user on the optimal settings to use.

I use Monte's mergAV to capture video. http://www.mergext.com This captures in .H264 and allows you to set the video quality by script so the user does not have to do it.

Martin Koob

[Nana]

Martin Koob thank you for your answer.

mergAV isn't an iOS external ?? We record videos on Windows/Mac...

Nana

[Martin Koob]

MergAV also works with Mac OS X. I use it in my Mac application and it works well. revVideoGrabber does not work with the FaceTime HD camera in newer model macs so I had to switch.

Martin

[Nana]

Dear Martin
do you have a sample stack that works with mergAV external on mac?

my code works only on my iphone. What am i missing?

Code: Select all

on openCard
 
   try
      mergAVCamCreate
   catch e
      answer e
   end try
   try
      mergAVCamSet "rect",the rect of grc "cam"
   catch e
      answer e
   end try
   try
      mergAVCamSet "visible","true"
   catch e
      answer e
   end try
   try
      mergAVCamSet "quality",the label of btn "quality"
   catch e
      answer e
   end try
end openCard

thank you
nana

[Martin Koob]

Sorry Nana,

I was away a couple of days so could not get to this.

I have attached a simple demo of capturing with MergAV on Mac OSX.

When I ran your code I got an error related to the quality setting. It may be that you are using a preset that is supported on iOS that is not supported on MacOSX.

Here are the lists of presets supported on the two OS's as best I can determine. I have included the links where I found these.

iOS Capture session presets
https://developer.apple.com/library/pre ... ut_Presets
AVCaptureSessionPresetPhoto;
AVCaptureSessionPresetHigh;
AVCaptureSessionPresetMedium;
AVCaptureSessionPresetLow;
AVCaptureSessionPreset352x288;
AVCaptureSessionPreset640x480;
AVCaptureSessionPreset1280x720;
AVCaptureSessionPreset1920x1080;
AVCaptureSessionPresetiFrame960x540;
AVCaptureSessionPresetiFrame1280x720;

Mac OS X Capture session presets
https://developer.apple.com/library/mac ... pture.html
AVCaptureSessionPresetHigh
AVCaptureSessionPresetMedium
AVCaptureSessionPresetLow
AVCaptureSessionPreset640x480
AVCaptureSessionPreset1280x720

If you are worried about video file size I would use Medium. That is what I used in this stack.

Also it is better to set the camera settings before you call mergAVCamCreate.

So in this stack when you click the 'Open Cam' button it will go to card 2 and create the camera.

When you click record it records a movie called 'output.mov' to the Movie folder. When you click the 'Close Cam' button it goes back to card 1 and sets the file name of the player on the card to the newly created movie.

Hope this gets you started with mergAV on the Mac.

Martin Koob

[Nana]

Dear Martin,

thank you very much for your answer. I tried the stack you send but with no luck. I still have the same exceptions.

I am on a Mac OSX Yosemite 10.10.2 and tested it LiveCode Commercial 5.5.2 & LiveCode Community 8.0.0

Nana

[Klaus]

Hi Nana,

quick question:
Did you install the external correctly?
LC needs to be pointed to new externals!

See here:
http://lessons.runrev.com/m/4071/l/6347 ... ne-builder


Best

Klaus

[Martin Koob]

Hi

I haven't used LiveCode 8 with mergAV yet. I am working in LC 6.7.3 commercial right now and it works there. I just did a test to see what the minimum version of LC that the mergAVCam demo stack will work with and I found it is LC 6.7.1 and later.

I tested the stack on Yosemite 10.10.1 and LC 6.7.1 and later and it works. Earlier versions I have did not work. It works in LC 7.0.5 as well. (these are all commercial)

I just tried the stack on LC 8 Community DP 2 and the preview would work when I clicked the Open Cam button but when I clicked record LiveCode crashed. I will submit a bug report to bugzilla and let Monte know.

One other thing is make sure you have the latest version of mergAV. Monte added some features for me and fixed some bugs so if you don't have the latest version that may be the problem.

Martin Koob

[Martin Koob]

I posted a bug report for the crash when starting recording with LC 8 DP2.

http://quality.runrev.com/show_bug.cgi?id=15530

Martin