frame rate in HD recordings

[humarf]

Hello,

I try to use avidemux2.6.3 on HD-recordings (720p) from my DVBS2 set top box (it's a dreambox recording in ts-format).
Avidemux is always detecting a frame rate of 100 fps - real rate is 50fps. Is there a way to fix this - could this be a bug? Using the frame rate filter does not work since I simply copy the video stream.

Thanks for ypur help

Regards
humarf

[bernd_b]

I can confirm this behaviour and uploaded a small example.
Mediainfo and ffprobe, e.g., confirm it to be 50fps. And the German TV stations claim to broadcast this way as well.

Loading the file into avidemux-2.6.x, the menu entry "File/Information" announce it to be 100 fps.

If you do a stream copy into ts-container, mediainfo and ffprobe will stick to report 50 fps for the copy.
If you do a stream copy into mkv-container, only mediainfo still claims the copy to be 50fps, ffprobe now shows 100 fps for the copy made by avidemux.

Here is the link to the sample:
http://www.datafilehost.com/d/1a588ecc

[mean]

Thanks for the sample

[mean]

The file seems to be 50 image/sec but 100 fields per sec

[bernd_b]

That is weird, at least mediainfo claims the file to be progressive:

Code Select Expand

mediainfo 50_or_100fps_org.ts
General
ID                                       : 32776 (0x8008)
Complete name                            : 50_or_100fps_org.ts
Format                                   : MPEG-TS
File size                                : 53.6 MiB
Duration                                 : 58s 530ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 7 679 Kbps

Video
ID                                       : 1601 (0x641)
Menu ID                                  : 132 (0x84)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L3.2
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 4 frames
Format settings, GOP                     : M=4, N=16
Codec ID                                 : 27
Duration                                 : 58s 500ms
Bit rate                                 : 6 653 Kbps
Width                                    : 1 280 pixels
Height                                   : 720 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 50.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.144
Stream size                              : 46.4 MiB (87%)



An why does stream copy change mediainfos mind?

[humarf]

Thanks for confirming the issue. I will test copying the stream to .ts. Maybe this fixes it as a work around.

On the other hand I can confirm that the recorded streams are all progressive videos. Nearly all free HD tv stations in Germany broadcast in 720p.

Best regards
Martin

[mean]

Let me recheck
Last time i looked, i saw one frame decoded every two, which usually happens for interlaced content
i.e.
field 1 => no image, field 2 => image, etc...

[humarf]

Last night I copied the file to a new ts-stream using ts-muxer capabilities of avidemux. But this not help. Resulting stream is at 100fps too, says avidemux. How did you do the streamcopy, please, that it is shown at 50fps?

Thanks for your help
humarf

[bernd_b]

Sorry for this misunderstanding:
My point was not that avidemux changes its mind, but the other way round:

If you do a stream copy into ts-container, mediainfo and ffprobe will stick to report 50 fps for the copy.

Which still means: Reloading the copy to avidemux leads again to a 100 fps identification there.

But I noticed another mentioning in the changelog:

Code Select Expand

Revision 8882 - Directory Listing
Modified Tue Aug 20 06:03:40 2013 UTC (26 hours, 14 minutes ago) by mean

[Editor] Check for doubled fps, take 2


I will try it hopefully soon.

[humarf]

Sounds promising 

[mean]

Looking into it, your sample definitively triggers a bug

[mean]

Should be ok starting from r8884

[bernd_b]

  works here as expected

[humarf]

  I have installed avidemux 2.6.5 now and it's working as expected. Thank you very much! 

Best regards
humarf