How to use MediaInfo to Troubleshoot Videos

How to provide SyncSketch Support with the information we need to correct problems without relinquishing protected content

There is a nearly limitless variety of ways to create a digital video clip. Occasionally, one format or another will cause problems when uploaded into SyncSketch. The best way to work with SyncSketch Support is to provide us a password-protected link to the review that demonstrates the trouble. We understand, however, that this is not always possible, and that arranging nondisclosure agreements etc. is a bit too cumbersome just to resolve a support issue.

However, we can try to reproduce the problem on our end if we have sufficient information about the troublesome movie file.  And if we can reproduce it, we can usually fix it.  What's more, there's an easy way to provide us the detailed metadata we need without revealing a single pixel of the actual movie data.

There is a utility called MediaInfo that will conveniently create a text file with the metadata we need that you can send to us.  You can use the online version, but it's a handy utility to have for examining differences between videos, so it's also useful to have as a Mac or Windows app.  It's free to download from the MediaArea web site, And can also be installed from the Mac App Store for US$1 (which adds useful integration features).

Using MediaInfo as an application

Simply drag the source movie file onto the application window or icon, then under the File menu, select Export:


The file this creates is a bit cryptic to those who are not video compression nerds, but it is a simple text file that will allow you to feel confident that you are not revealing any protected data. You can remove anything you see that you don't care to reveal, like the folder names up at the top. 

It will look something like this:

Complete name : /Users/customer/Movies/testmedia/bbb_sunflower_2160p_60fps_normal.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/avc1)
File size : 642 MiB
Duration : 10 min 34 s
Overall bit rate : 8 488 kb/s
Movie name : Big Buck Bunny, Sunflower version
Performer : Blender Foundation 2008, Janus Bager Kristensen 2013
Composer : Sacha Goedegebure
Genre : Animation
Encoded date : UTC 2013-12-17 16:40:26
Tagged date : UTC 2013-12-17 16:40:26
Comment : Creative Commons Attribution 3.0 -
com : Jan Morgenstern

ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L5.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 10 min 34 s
Bit rate : 8 000 kb/s
Maximum bit rate : 35.1 Mb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 60.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.016
Stream size : 605 MiB (94%)
Writing library : x264 core 120
Encoding settings : cabac=1 / ref=4 / deblock=1:1:1 / analyse=0x3:0x133 / me=tesa / subme=11 / psy=1 / psy_rd=0.40:0.00 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=12 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=16 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=2pass / mbtree=1 / bitrate=8000 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:0.60
Encoded date : UTC 2013-12-17 16:40:26
Tagged date : UTC 2013-12-17 16:40:29
Codec configuration box : avcC

Audio #1
ID : 2
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 3
Format settings : Joint stereo / MS Stereo
Codec ID : mp4a-6B
Duration : 10 min 34 s
Bit rate mode : Constant
Bit rate : 160 kb/s
Maximum bit rate : 165 kb/s
Channel(s) : 2 channels
Sampling rate : 48.0 kHz
Frame rate : 41.667 FPS (1152 SPF)
Compression mode : Lossy
Stream size : 12.1 MiB (2%)
Writing library : LAME3.99r
Encoding settings : -m j -V 4 -q 3 -lowpass 17.5 -b 160
Encoded date : UTC 2013-12-17 16:40:28
Tagged date : UTC 2013-12-17 16:40:29

Audio #2
ID : 3
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Codec ID : ac-3
Duration : 10 min 34 s
Bit rate mode : Constant
Bit rate : 320 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Stream size : 24.2 MiB (4%)
Service kind : Complete Main
Encoded date : UTC 2013-12-17 16:40:28
Tagged date : UTC 2013-12-17 16:40:29

With this information, SyncSketch Support can create a similar movie file that may exhibit the same behavior, allowing us to come up with a solution.

Other Things That Can Help

Having this metadata helps us make sure that the files we're testing with closely match the characteristics of your movie file.  But there's a little more information you can provide that would help us on the way to getting you solutions.

Good: What application did you use?

If you can tell us what tool generated the video file that's giving you trouble, it can really give us a head start on reproducing the problem.  This could be an application like Final Cut Pro, Blender or Adobe After Effects, or a dedicated transcoding application, or even a command-line utility.

Better: What settings did you use?

Most likely, the problem isn't with your movies, but rather how they are encoded.  With many of these tools there are dozens of settings that can be configured to render a movie file out.  Any of those settings you can share with us are incredibly helpful.  Some applications will allow those settings to be saved as a file and shared – such files would absolutely ideal. 

Best: Could you create "safe" content and share it with us?

We certainly understand that your projects are confidential.  But if you created some content that is not proprietary, using the same encoding process, that file would be perfect for us to troubleshoot your issue.  For example, if you are having trouble with movies generated from your team's favorite transcoding application, you could download a Creative Commons short like Big Buck Bunny, transcode that, and deliver the resulting file to us.  That might be all we need to start working on a fix or determining a workaround.