Extra frames sometimes appear at the end of split videos

[typoman]

First of all thank you for such a great tool! It seems that the precise flag (-p or --precise) has been changed to preset and does not work anymore although it's still written in the readme of the repo. I used the content detect option but still the cuts are not precise and there are some frames that overlap with the previous scene. Is there any way to cut the scenes more precisely?

[Breakthrough]

Hi @typoman;

The default behaviour of PySceneDetect now is what precise mode was before. Scenes should be split accurately and re-encoded by ffmpeg when using the split-video command. To disable this and go back to the old behaviour, supply the -c/--copy flag to the split-video command.

Are you seeing a different/unexpected result? How many frames are overlapping? Could you provide some more details, like the complete command/example output?

Thanks!

[Breakthrough]

Hi @typoman;

Were you able to validate that frame cuts were correct or not with the new version? I forgot to mention, you also need to have ffmpeg installed for precise cutting to work.

Thanks!

[typoman]

Hi @Breakthrough,

I had installed ffmpeg when I was doing the tests. I'm sorry for the delayed answer but since I was in a hurry I just used another solution to split the videos manually. My config is OS X 10.13.6 and I think I used default flags. In the split videos, I saw frames from the previous scene just for the first or two frames. The codec was h264 and the format was mp4. If you want I can perform a test on a video (or a link) you provide and send you back what I get then you can compare results?

[Breakthrough]

Hi @typoman;

You can try with the goldeneye.mp4 file from here:
https://github.com/Breakthrough/PySceneDetect/tree/resources/tests/goldeneye

It should match the expected output on the examples page on readthedocs.

Would you be able to share with me one of the files where you're experiencing this behaviour? Is the video fixed-framerate or variable framerate? (One thing PySceneDetect does not deal with is varaible framerate videos...)

Thank you!

[typoman]

I can't share my files but I encounter the same issue with your sample. The command I used:

scenedetect --input goldeneye.mp4 detect-content split-video

When I open the first scene in QuickTime it contains two frames of the the next scene at the end. Here is the result of all scenes:

Archive.zip

[Breakthrough]

@typoman can you also provide all other information as per this link (e.g. operating system, output log in debug mode)?

You can copy and paste the template into a comment here, or attach the relevant information to the first post.

Thank you.

[typoman]

Bug/Issue Description:
A clear and concise description of what the bug or issue is - in other words, what the unexpected behavior or output is.

Imprecise cutting (as mentioned above)

Required Information:
Provide the following information to assist with reporting the bug:

scenedetect -v debug -l BUG_REPORT.txt --input goldeneye.mp4 detect-content split-video

Output:

ffmpeg version 3.4.2 Copyright (c) 2000-2018 the FFmpeg developers
  built with Apple LLVM version 9.0.0 (clang-900.0.39.2)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/3.4.2 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --disable-jack --enable-gpl --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --enable-videotoolbox --disable-lzma
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/bahmaneslami/Downloads/goldeneye.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    creation_time   : 2016-02-03T04:12:42.000000Z
  Duration: 00:01:22.59, start: 0.000000, bitrate: 1533 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x544 [SAR 1:1 DAR 40:17], 1338 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 191 kb/s (default)
    Metadata:
      creation_time   : 2016-02-03T04:12:42.000000Z
      handler_name    : IsoMedia File Produced by Google, 5-11-2011
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[libx264 @ 0x7fe04c810a00] using SAR=1/1
[libx264 @ 0x7fe04c810a00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x7fe04c810a00] profile High, level 3.1
[libx264 @ 0x7fe04c810a00] 264 - core 152 r2854 e9a5903 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=12 lookahead_threads=4 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=1 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=10 rc=crf mbtree=1 crf=22.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'goldeneye-Scene-001.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    encoder         : Lavf57.83.100
    Stream #0:0(und): Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 1280x544 [SAR 1:1 DAR 40:17], q=-1--1, 23.98 fps, 24k tbn, 23.98 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc57.107.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 191 kb/s (default)
    Metadata:
      creation_time   : 2016-02-03T04:12:42.000000Z
      handler_name    : IsoMedia File Produced by Google, 5-11-2011
frame=   91 fps=0.0 q=-1.0 Lsize=     448kB time=00:00:03.73 bitrate= 982.6kbits/s speed=8.14x    
video:356kB audio:88kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.938643%
[libx264 @ 0x7fe04c810a00] frame I:1     Avg QP:19.18  size: 28013
[libx264 @ 0x7fe04c810a00] frame P:24    Avg QP:19.86  size:  8254
[libx264 @ 0x7fe04c810a00] frame B:66    Avg QP:21.60  size:  2085
[libx264 @ 0x7fe04c810a00] consecutive B-frames:  3.3%  0.0%  0.0% 96.7%
[libx264 @ 0x7fe04c810a00] mb I  I16..4: 19.5% 58.6% 21.9%
[libx264 @ 0x7fe04c810a00] mb P  I16..4: 12.5% 10.1%  0.5%  P16..4: 30.0% 11.2%  4.7%  0.0%  0.0%    skip:30.9%
[libx264 @ 0x7fe04c810a00] mb B  I16..4:  1.6%  1.3%  0.0%  B16..8: 14.2%  3.0%  0.1%  direct: 7.8%  skip:72.0%  L0:45.5% L1:45.1% BI: 9.4%
[libx264 @ 0x7fe04c810a00] 8x8 transform intra:45.7% inter:48.6%
[libx264 @ 0x7fe04c810a00] coded y,uvDC,uvAC intra: 31.0% 57.2% 8.9% inter: 3.4% 17.8% 0.1%
[libx264 @ 0x7fe04c810a00] i16 v,h,dc,p: 45% 40% 13%  3%
[libx264 @ 0x7fe04c810a00] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28% 29% 35%  1%  1%  1%  1%  1%  2%
[libx264 @ 0x7fe04c810a00] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 27% 39%  8%  4%  5%  5%  4%  5%  4%
[libx264 @ 0x7fe04c810a00] i8c dc,h,v,p: 41% 33% 23%  3%
[libx264 @ 0x7fe04c810a00] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x7fe04c810a00] kb/s:766.73
 bahmaneslami@B-M-E  ~/Downloads   master ?                                                                                                              ✔  1383  17:09:51

2. Add -v debug -l BUG_REPORT.txt to the beginning of the command, then re-run PySceneDetect and attach the generated BUG_REPORT.txt file.

Expected Behavior:
A clear and concise description of what you expected to happen.

Precise cutting!

Computing Environment:

• OSX: 10.13.6 BuildVersion: 17G6030
• Python Version: 3.7.3
• OpenCV Version: 4.0.0

BUG_REPORT.txt

[Breakthrough]

Hi @typoman;

I've submitted an updated version of PySceneDetect, v0.5.1, which includes various bugfixes. My apologies however, but I'm having trouble replicating the behavior you're seeing (I'm only able to test on Windows/Linux). Can you double-check if this issue is fixed in v0.5.1 on OSX?

Thank you!

Edit: Would you also be able to provide the output scene list, in .csv format, for goldeneye.mp4? I would like to compare the detected cut positions to those in the resources branch.