I'm using Tracker 5.0.1 (and have been using it since early 4.x) on Windows 10 with my Physics classes.
We have Casio Exilim High Speed cameras that record in .mov format. Mediainfo software says they are MPEG-4 Quicktime AVC format.
I can load them into Tracker fine. They play and step forward ok. But if I try to step back (one frame), the video freezes. The message log says this (multiple times):
'CONSOLE: 14:41:02.893 [AWT-EventQueue-0] ERROR org.ffmpeg - [h264 @ 0x179fa330] number of reference frames exceeds max (probably corrupt input), discarding one'
I noticed in Mediainfo that the frame rate of the MOV file says '29.970 (30000/1001) FPS'.
So I tried using a media converter to just change the frame rate to 30 fps (nothing else - still Quicktime MPEG4 AVC mov file).
And hey presto - the video is fine. I can step back without an issue, and nothing untoward in the message log.
The problem is that the Casio Exilim only saves as the 29.970 MOV file, so I would have to get my students to convert the file to 30fps every time they wanted to analyse anything. Can Tracker address this issue?
I don't know why Xuggle (which uses ffmpeg) can't handle your video format (it may be a newer codec than the ffmpeg version) but there is probably no solution except to convert. However, the problem is probably not the frame rate and if you convert to a different frame rate the time data will not be accurate (29.97 fps is indeed a standard). I suggest you convert but change some other property than the frame rate. One possibility is to convert to FLV, a format that Xuggle handles well.
Hope this helps. Doug
> > We have Casio > Exilim High Speed cameras that record in .mov format. > Mediainfo software says they are MPEG-4 Quicktime > AVC format. > > I can load them into Tracker fine. They > play and step forward ok. But if I try to step back > (one frame), the video freezes. The message log says > this (multiple times): > > 'CONSOLE: 14:41:02.893 [AWT-EventQueue-0] > ERROR org.ffmpeg - [h264 @ 0x179fa330] number of reference > frames exceeds max (probably corrupt input), discarding > one' > > I noticed in Mediainfo that the frame rate of > the MOV file says '29.970 (30000/1001) FPS'. > > So I > tried using a media converter to just change the frame > rate to 30 fps (nothing else - still Quicktime MPEG4 > AVC mov file). > > And hey presto - the video is fine. > I can step back without an issue, and nothing untoward > in the message log. > > The problem is that the Casio > Exilim only saves as the 29.970 MOV file, so I would > have to get my students to convert the file to 30fps > every time they wanted to analyse anything. Can Tracker > address this issue? > > Cheers, > Steve
OK. I tried converting to FLV instead without changing frame rate (or anything else). It works! Going back a frame is fine now.
Out of curiosity I opened the original 29.97fps MOV file with MediaInfo and compared to working 29.97fps FLV file. I have pasted both here in case you can shed any light on the cause. I noticed that the MOV file frame rate is reported as '29.970 (30000/1001) FPS', but the FLV is '29.970 FPS' without the bracketed part.
Cheers, Steve
MOV file (freezes) ---------
General Complete name : C:\Users\steve\Desktop\aaaa.MOV Format : MPEG-4 Format profile : QuickTime Codec ID : qt 2010.08 (qt /caqv) File size : 26.6 MiB Duration : 21 s 755 ms Overall bit rate mode : Variable Overall bit rate : 10.3 Mb/s Encoded date : UTC 2012-03-28 01:26:39 Tagged date : UTC 2012-03-28 01:26:39 Writing application : Casio Digital Camera
Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : Main@L3.1 Format settings, CABAC : Yes Format settings, RefFrames : 1 frame Format settings, GOP : N=1 Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 21 s 755 ms Bit rate mode : Variable Bit rate : 10.3 Mb/s Width : 640 pixels Height : 480 pixels Display aspect ratio : 4:3 Frame rate mode : Constant Frame rate : 29.970 (30000/1001) FPS Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 1.115 Stream size : 26.6 MiB (100%) Language : English Encoded date : UTC 2012-03-28 01:26:39 Tagged date : UTC 2012-03-28 01:26:39
---------------------
FLV file (works) ---------
General Complete name : C:\Users\steve\Desktop\aaaa.flv Format : Flash Video File size : 3.08 MiB Duration : 21 s 755 ms Overall bit rate : 1 188 kb/s Writing application : Lavf57.19.100
