Understand if an AVCaptureDeviceFormat suits video recording

Question

In an app that I'm developing I'd like to let the user choose the the resolution of video recording. Due to specification, I can't use AVCaptureSessionPreset constants.
Getting format list there are resolutions above 3000px that of course can't work for video grabbing but only for photo shooting.

AVCaptureDeviceFormat: 0x17020c830 'vide'/'420f' 3264x2448, { 2- 30 fps}, HRSI:3264x2448, fov:58.040, max zoom:153.00 (upscales @1.00), AF System:2, ISO:29.0-1856.0, SS:0.000013-0.500000

I can't find a way to see if a specific format is suitable for video recording.
The problem is that with this kind of resolution if I try to grab a video the app generates an exception saying that there is no active or enabled connection.

-[AVCaptureMovieFileOutput startRecordingToOutputFileURL:recordingDelegate:] - no active/enabled connections.

I also don't want to hardcode limits for each kind of device.
I can't also try to cap the limit to AVCaptureSessionPresetHigh because as stated in an Apple note is not the actual maximum format.
Is there a way to understand if a AVCaptureDeviceFormat is suitable for grabbing video?

score 2 · Accepted Answer · answered May 06 '15 at 11:50

2

After setting all the connections with the selected -activeFormat check if the current AVCaptureConnection isActive or observe using KVO the property -active. If it is no the format is not available for video grabbing, if it is yes it can be used.

answered May 06 '15 at 11:50

Andrea

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Thank you for posting this solution! – AlexeyVMP Jun 17 '15 at 09:45
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Upvoted. Good idea for debugging and testing things, but not for production code, since it takes several seconds to go through all the formats on the iPhone 5s. The app appears to have hung. – Kartick Vaddadi Sep 17 '17 at 11:53

Understand if an AVCaptureDeviceFormat suits video recording

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