We are having an issue with frame rate detection across multiple files, file types, devices, and operating systems. We are all running ELAN 6.3. It seems that ELAN is not correctly sensing the framerate and the default frame rate differs based on device. The framerate of the videos is NTSC 1/30 and those using macs are getting a default frame rate of PAL 1/25 and at least for some PCs, the default frame rate is PAL-50fps 1/50. These defaults are the same for multiple video files across both .mp4 and .mov file types. I’ve checked the frame rate in the metadata, and the metadata is correct.
A smaller point, when setting the frame length, the menu option set frame length initially appears grayed out and in order to get the frame length option to appear, I have to click into interlinearization mode and then back to annotation mode. This is also true across devices and OS. Also, after resetting the frame length to the correct frame length and saving the file, the file defaults back to whatever the previous default was, so the frame length must be set every time we reopen the file.
Hello, thanks for reporting this.
On both Mac and Windows ELAN supports several “media frameworks” for playback of audio and/or video. In principle media properties are, or should be, detected by the framework that is used for a specific file. Only if the frame rate has not been detected by the framework, the Set Frame Length option should be enabled. ELAN has no way to check if the reported frame duration or frame rate is correct, so it might be in some cases that the framework reports a detected frame rate, but that it is wrong. All media frameworks write some information about the media files they open in the log (View->View Log...).
On macOS the default framework is labeled JAVF Media Player in the log (AV Foundation Player in the Player Info window) and while checking the issue you raise, I noticed that in the log the frame duration and frame rate seem to be detected correctly initially, but in the end a frame duration of 0.0 sec. is reported. I still have to check the code, but it seems that that is a bug in the current implementation of that player. If so, we’ll have to fix that for the next release.
On Windows the default framework for .mp4 files is labeled JMMFMediaPlayer in the log (JMMF - Java with Microsoft Media Player in the Player Info window). Here detection of the frame duration seems to work correctly, at least with the files that I have. There’s no default framework for .mov files on Windows; these files might not play at all, or be played by the JMMFPlayer or the VLC based player. Frame rate detection may or may not work correctly.
Again in principle, the Set Frame Length should be disabled if the player framework claims to have detected the frame duration or frame rate. The fact that the menu item becomes enabled after switching to Interlinearization mode and back, is due to another bug that we’ll have to repair. Why this menu item isn’t enabled on macOS with the incorrect frame rate detection is also something that we have to check.
Apologies for the inconvenience this all causes!
-Han
