Modern containers govern the time component of presentation of video (and audio) frames using timestamps, rather than framerate. So, instead of recording a video as 25 fps, and thus implying that each frame should be drawn 0.04 seconds apart, they store a timestamp for each frame e.g.

     Frame      pts_time
       0          0.00
       1          0.04
       2          0.08
       3          0.12
       ...

 For the sake of precise resolution of these time values, a timebase is used i.e. a unit of time which represents one tick of a clock, as it were. So, a timebase of `1/75` represents 1/75th of a second. The **P**resentation **T**ime**S**tamps are then denominated in terms of this timebase. Timescale is simply the reciprocal of the timebase. FFmpeg shows the timescale as the `tbn` value in the readout of a stream.

    Timebase = 1/75; Timescale = 75
     Frame        pts           pts_time
       0          0          0 x 1/75 = 0.00
       1          3          3 x 1/75 = 0.04 
       2          6          6 x 1/75 = 0.08
       3          9          9 x 1/75 = 0.12
       ...

This method of regulating time allows variable frame-rate video.

I&#39;m using the Google Play services in my Android app so I have the dependency in my `build.gradle`.

    compile &#39;com.google.android.gms:play-services:10.2.1&#39;

But Android Studio shows a warning for it: `Avoid using bundled version of Google Play services SDK`.

[![Android warning][1]][1]

What does this warning mean? How should I avoid it? I&#39;ve googled a lot without finding much related info. 

  [1]: https://i.stack.imgur.com/aXdwq.png

How to suppress the &quot;Avoid using bundled version of Google Play services SDK&quot; warning?

I have a deprecation warning in Django 1.11:

    RemovedInDjango20Warning: Passing a 3-tuple to django.conf.urls.include() is deprecated. Pass a 2-tuple containing the list of patterns and app_name, and provide the namespace argument to include() instead.
      url(r&#39;^admin/&#39;, include(admin.site.urls))

In Django 2.0 this gives the error:

    django.core.exceptions.ImproperlyConfigured: Passing a 3-tuple to include() is not supported. 
    Pass a 2-tuple containing the list of patterns and app_name, and provide the namespace argument to include() instead.

How should I change `url(r&#39;^admin/&#39;, include(admin.site.urls))`? I tried to look at the documentation, but I have no clue ...

Here is my urls.py:

    from django.conf.urls import include, url
    from django.contrib import admin
    admin.autodiscover()
    
    urlpatterns = [
        url(r&#39;^admin/&#39;, include(admin.site.urls)),
        url(r&#39;^admin/django-ses/&#39;, include(&#39;django_ses.urls&#39;)),
        url(r&#39;^api/1.0/&#39;, include(&#39;feedcrunch_api_v1.urls&#39;)),
        url(r&#39;^oauth/&#39;, include(&#39;oauth.urls&#39;)),
        url(r&#39;^@(?P&lt;feedname&gt;\w+)/admin/&#39;, include(&#39;feedcrunch_rssadmin.urls&#39;)),
        url(r&#39;^@(?P&lt;feedname&gt;\w+)/&#39;, include(&#39;feedcrunch_rssviewer.urls&#39;)),
        url(r&#39;^api-auth/&#39;, include(&#39;rest_framework.urls&#39;, namespace=&#39;rest_framework&#39;)),
        url(r&#39;&#39;, include(&#39;feedcrunch_home.urls&#39;)),
    ]



Django Deprecation Warning or ImproperlyConfigured error - Passing a 3-tuple to django.conf.urls.include() is not supported

There does not seem to be any explanation online as to what these are. People talk about them a lot. I just want to know what they are and why they are significant. Using -video_track_timescale, how would I determine a number for it? Is it random? Should it be 0?

What is video timescale, timebase, or timestamp in ffmpeg?

<p>There does not seem to be any explanation online as to what these are. People talk about them a lot. I just want to know what they are and why they are significant. Using -video_track_timescale, how would I determine a number for it? Is it random? Should it be 0?</p>


I have some kind of a strange problem. I try to create a website with a looped background video. The code looks like this one:

&lt;!-- begin snippet: js hide: false console: true babel: false --&gt;

&lt;!-- language: lang-html --&gt;

    &lt;video src=&quot;video/bg.mp4&quot; style=&quot;z-index: -1;object-fit: cover;&quot; poster=&quot;video/bg.jpg&quot; autobuffer autoplay loop muted&gt;&lt;/video&gt;

&lt;!-- end snippet --&gt;

This works perfectly fine on most browsers (IE struggles with this object-fit thing but I don&#39;t mind) but on iPhone the video won&#39;t autoplay but on iPad it does. I already read the [New &lt;video&gt; Policies for iOS][1] and I think I meet the requirements (otherwise iPad won&#39;t autoplay). I did some other testing:

 - Removing overlaying divs won&#39;t fix it 
 - Removing z-index won&#39;t fix it
 - Wifi or Cellular doesn&#39;t make a difference 
 - Video filesize doesn&#39;t make a difference, too

Am I doing it wrong or does iPhone simply won&#39;t autoplay videos and always requires interaction? I only care for iOS 10, I know that the requirements were different on iOS 9

  [1]: https://webkit.org/blog/6784/new-video-policies-for-ios/ &quot;New &amp;lt;video&amp;gt; Policies for iOS&quot;

HTML5 Video autoplay on iPhone

I want to use ffmpeg to accelerate video encode and decode with an NVIDIA GPU.
  
From [NVIDIA&#39;s website][1]: 
 
&gt; NVIDIA GPUs contain one or more hardware-based decoder and encoder(s) (separate from the CUDA cores) which provides fully-accelerated hardware-based video decoding and encoding for several popular codecs. With decoding/encoding offloaded, the graphics engine and the CPU are free for other operations.

My question is: can I use CUDA cores to encode and decode video, maybe faster?


  [1]: https://developer.nvidia.com/nvidia-video-codec-sdk

GPU-accelerated video processing with ffmpeg

I currently try to make a movie out of images, but i could not find anything helpful .

Here is my code so far:

    import time
    
    from PIL import  ImageGrab
    
    x =0
    
    while True:
        try:
            x+= 1
            ImageGrab().grab().save(&#39;img{}.png&#39;.format(str(x))
        except:
            movie = #Idontknow
            for _ in range(x):
                movie.save(&quot;img{}.png&quot;.format(str(_)))
    
    movie.save()



How to make a movie out of images in python

I&#39;m getting the error message..

&gt; Uncaught (in promise) DOMException: play() failed because the user didn&#39;t interact with the document first.

..when trying to play video on desktop using Chrome version 66.

I did find an ad that began playback automatically on a website however using the following HTML:

    &lt;video
        title=&quot;Advertisement&quot;
        webkit-playsinline=&quot;true&quot;
        playsinline=&quot;true&quot;
        style=&quot;background-color: rgb(0, 0, 0); position: absolute; width: 640px; height: 360px;&quot;
        src=&quot;http://ds.serving-sys.com/BurstingRes/Site-2500/Type-16/1ff26f6a-aa27-4b30-a264-df2173c79623.mp4&quot;
        autoplay=&quot;&quot;&gt;&lt;/video&gt;

So is by-passing Chrome v66&#39;s autoplay blocker really as easy as just adding the `webkit-playsinline=&quot;true&quot;`, `playsinline=&quot;true&quot;`, and `autoplay=&quot;&quot;` attributes to the `&lt;video&gt;` element? Are there any negative consequences to this?

How to handle &quot;Uncaught (in promise) DOMException: play() failed because the user didn&#39;t interact with the document first.&quot; on Desktop with Chrome 66?

Situation:
----------
I am trying to export video with some parameters like video bit rate, audio bit rate, frame rate, changing video resolution, etc. Note that I am letting the user set the video frame rate in fractions; like user can set the video frame rate say, 23.98.

I use **AVAssetWriter** and **AVAssetReader** for this operation. I use [AVAssetWriterInputPixelBufferAdaptor][1] for writing the sample buffers.

Everything else works just fine, except the **video frame rate**.


What I have tried:
------------------

 1. Setting the **AVAssetWriter.movieTimeScale** as suggested [here][2]. Which does change the video frame rate but also makes the video sluggish. ([gist here][3])

----------
 2. Setting **AVVideoExpectedSourceFrameRateKey**. Which does not help. ([gist here][4])

----------
 3. Setting **AVAssetWriterInput.mediaTimeScale**. Again, it changes the video frame rate but makes the video sluggish as *AVAssetWriter.movieTimeScale* does. The video shows different frames at some point and sometimes it sticks and resumes again. ([gist here][5])

----------
 4. Using **AVAssetReaderVideoCompositionOutput** and setting **AVMutableVideoComposition.frameDuration**; just like [SDAVAssetExportSession][6] does. Ironically with SDAVAssetExportSession code, the video is being exported just at the right frame rate that I want, but it just does not work in my code. [gist here][7]

I am not sure why it won&#39;t work with my code. The issue with this approach is it always returns nil from *AVAssetReaderVideoCompositionOutput.copyNextSampleBuffer()*.

----------
 5. Manually changing the timestamp of the frame with **CMSampleTimingInfo**, as suggested [here][8] Something like:

```
var sampleTimingInfo = CMSampleTimingInfo()
var sampleBufferToWrite: CMSampleBuffer?

CMSampleBufferGetSampleTimingInfo(vBuffer, at: 0, timingInfoOut: &amp;sampleTimingInfo)

sampleTimingInfo.duration = CMTimeMake(value: 100, timescale: Int32(videoConfig.videoFrameRate * 100))

sampleTimingInfo.presentationTimeStamp = CMTimeAdd(previousPresentationTimeStamp, sampleTimingInfo.duration)

previousPresentationTimeStamp = sampleTimingInfo.presentationTimeStamp

let status = CMSampleBufferCreateCopyWithNewTiming(allocator: kCFAllocatorDefault, sampleBuffer: vBuffer,sampleTimingEntryCount: 1, sampleTimingArray: &amp;sampleTimingInfo, sampleBufferOut: &amp;sampleBufferToWrite)
```
With this approach, I do get the frame rate set just right, but it increases the video duration (as mentioned in the comment of that question’s answer). I think at some point I may have to discard some frames (if the target frame rate is lower; I need to lower the frame rate in most of the cases). 

If I know that if I want 30fps, and my current frame rate is 60fps, it&#39;s simple to discard every second frame and setting the SampleBuffer time accordingly.

If I go with this approach(i.e. setting 23.98 fps), how do I decide which frame to discard and if the target frame rate is higher, which frame to duplicate? Reminder: the frame rate could be in fractions.

----------


  [1]: https://developer.apple.com/documentation/avfoundation/avassetwriterinputpixelbufferadaptor
  [2]: https://stackoverflow.com/a/16911799/1208191
  [3]: https://gist.github.com/chauhan130/31b8bf648f0071a949d1627c78315056#file-gistfile1-txt-L16
  [4]: https://gist.github.com/chauhan130/31b8bf648f0071a949d1627c78315056#file-gistfile1-txt-L38
  [5]: https://gist.github.com/chauhan130/31b8bf648f0071a949d1627c78315056#file-gistfile1-txt-L50
  [6]: https://github.com/rs/SDAVAssetExportSession
  [7]: https://gist.github.com/chauhan130/8d2f5bbe680353961fecacb80e254b92#file-gistfile1-txt-L77
  [8]: https://stackoverflow.com/a/49236475/1208191

Problem setting video frame rate using AVAssetWriter/AVAssetReader

I am trying to convert a video clip (MP4, yuv420p) from 30 fps to 24 fps. The number of frames is correct so my output should change from 20 minutes at 30fps to 25 minutes at 24fps. Everything else should remain the same.

Try as I might everything I try with ffmpeg converts the frame rate but changes the number of frames to keep the same duration or changes the duration without altering the framerate.

So I have been typically trying things like;

    ffmpeg -y -r 30 -i seeing_noaudio.mp4 -r 24 seeing.mp4

(I&#39;m doing this on windows but normally would be on linux). That converts the framerate but drops frames so the total duration is unaltered.

Or I have tried 

    ffmpeg -y -i seeing_noaudio.mp4 -filter:v &quot;setpts=1.25*PTS&quot; seeing.mp4

Which changes the duration but not the framerate.

Surely I should be able to do this with a single ffmpeg command without having to reencode or even as some people suggested going back to the original raw frames.

Help please


Using ffmpeg to change framerate

I have dockerized an app which has ffmpeg installed in it via libav-tools. The app launches without problem, yet the problem occured when fluent-ffmpeg npm module tried to execute ffmpeg command, which was not found. When I wanted to check the version of the ffmpeg and the linux distro set up in the image, I used `sudo docker exec -it c44f29d30753 &quot;lsb_release -a&quot;` command, but it gave the following error: `OCI runtime exec failed: exec failed: container_linux.go:296: starting container process caused &quot;exec: \&quot;lsb_release -a\&quot;: executable file not found in $PATH&quot;: unknown`

Then I realized that it gives me the same error with all the commands that I try to run inside the image or the container.

    OCI runtime exec failed: exec failed: container_linux.go:296: starting container process caused &quot;exec: \&quot;ffmpeg -a\&quot;: executable file not found in $PATH&quot;: unknown

This is my Dockerfile:

    FROM ubuntu:xenial
    FROM node
    RUN apt-get -y update
    RUN apt-get --yes install libav-tools
    RUN mkdir -p /usr/src/app
    WORKDIR /usr/src/app
    COPY package.json /usr/src/app
    RUN npm install
    COPY . /usr/src/app
    RUN npm run build
    ENV NODE_ENV production
    EXPOSE 8000
    CMD [&quot;npm&quot;, &quot;run&quot;, &quot;start:prod&quot;]

I would kindly ask for your help. Thank you very much!

OCI runtime exec failed: exec failed: (...) executable file not found in $PATH&quot;: unknown

I want to add a logo to a video using FFMPEG. I encountered this error: &quot;Too many packets buffered for output stream 0:1.&quot;, &quot;Conversion Failed.&quot;. I tried with diffent pictures and videos, always got the same error. Google didn&#39;t help much either. I found a thread 

    C:\Users\Anwender\OneDrive - IT-Center Engels\_Programmierung &amp; Scripting\delphi\_ITCE\Tempater\Win32\Debug\ffmpeg\bin&gt;ffmpeg ^
    Mehr? -i C:\Users\Anwender\Videos\CutErgebnis.mp4 ^
    Mehr? -i C:\Users\Anwender\Pictures\pic.png ^
    Mehr? -filter_complex &quot;overlay=0:0&quot; ^
    Mehr? C:\Users\Anwender\Videos\Logo.mp4
    ffmpeg version N-90054-g474194a8d0 Copyright (c) 2000-2018 the FFmpeg developers
      built with gcc 7.2.0 (GCC)
      configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libmfx --enable-amf --enable-cuda --enable-cuvid --enable-d3d11va --enable-nvenc --enable-dxva2 --enable-avisynth
      libavutil      56.  7.101 / 56.  7.101
      libavcodec     58. 11.101 / 58. 11.101
      libavformat    58.  9.100 / 58.  9.100
      libavdevice    58.  1.100 / 58.  1.100
      libavfilter     7. 12.100 /  7. 12.100
      libswscale      5.  0.101 /  5.  0.101
      libswresample   3.  0.101 /  3.  0.101
      libpostproc    55.  0.100 / 55.  0.100
    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from &#39;C:\Users\Anwender\Videos\CutErgebnis.mp4&#39;:
      Metadata:
        major_brand     : isom
        minor_version   : 512
        compatible_brands: isomiso2avc1mp41
        encoder         : Lavf58.9.100
        comment         : Captured with Snagit 13.1.3.7993
                        : Microphone - Mikrofon (Steam Streaming Microphone)
                        :
      Duration: 00:01:51.99, start: 0.015011, bitrate: 148 kb/s
        Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1918x718 [SAR 1:1 DAR 959:359], 149 kb/s, 14.79 fps, 15 tbr, 15k tbn, 30 tbc (default)
        Metadata:
          handler_name    : VideoHandler
        Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 1 kb/s (default)
        Metadata:
          handler_name    : SoundHandler
    Input #1, png_pipe, from &#39;C:\Users\Anwender\Pictures\pic.png&#39;:
      Duration: N/A, bitrate: N/A
        Stream #1:0: Video: png, pal8(pc), 400x400, 25 tbr, 25 tbn, 25 tbc
    File &#39;C:\Users\Anwender\Videos\Logo.mp4&#39; already exists. Overwrite ? [y/N] y
    Stream mapping:
      Stream #0:0 (h264) -&gt; overlay:main (graph 0)
      Stream #1:0 (png) -&gt; overlay:overlay (graph 0)
      overlay (graph 0) -&gt; Stream #0:0 (libx264)
      Stream #0:1 -&gt; #0:1 (aac (native) -&gt; aac (native))
    Press [q] to stop, [?] for help
    Too many packets buffered for output stream 0:1.
    [aac @ 000001f4c5257a40] Qavg: 65305.387
    [aac @ 000001f4c5257a40] 2 frames left in the queue on closing
    Conversion failed!

My FFMPEG Version:
ffmpeg-20180322-ed0e0fe-win64-static

Details about the Video:

        C:\Users\Anwender\OneDrive - IT-Center Engels\_Programmierung &amp; Scripting\delphi\_ITCE\Tempater\Win32\Debug\ffmpeg-20180322-ed0e0fe-win64-static\bin&gt;ffprobe.exe C:\Users\Anwender\Videos\CutErgebnis.mp4
    ffprobe version N-90399-ged0e0fe102 Copyright (c) 2007-2018 the FFmpeg developers
      built with gcc 7.3.0 (GCC)
      configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
      libavutil      56. 11.100 / 56. 11.100
      libavcodec     58. 15.100 / 58. 15.100
      libavformat    58. 10.100 / 58. 10.100
      libavdevice    58.  2.100 / 58.  2.100
      libavfilter     7. 13.100 /  7. 13.100
      libswscale      5.  0.102 /  5.  0.102
      libswresample   3.  0.101 /  3.  0.101
      libpostproc    55.  0.100 / 55.  0.100
    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from &#39;C:\Users\Anwender\Videos\CutErgebnis.mp4&#39;:
      Metadata:
        major_brand     : isom
        minor_version   : 512
        compatible_brands: isomiso2avc1mp41
        encoder         : Lavf58.9.100
        comment         : Captured with Snagit 13.1.3.7993
                        : Microphone - Mikrofon (Steam Streaming Microphone)
                        :
      Duration: 00:01:51.99, start: 0.015011, bitrate: 148 kb/s
        Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1918x718 [SAR 1:1 DAR 959:359], 149 kb/s, 14.79 fps, 15 tbr, 15k tbn, 30 tbc (default)
        Metadata:
          handler_name    : VideoHandler
        Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 1 kb/s (default)
        Metadata:
          handler_name    : SoundHandler



Content Type	Original Author	Original Content on Stackoverflow
Question	Please Help	View Question on Stackoverflow
Solution 1 - Video	Gyan	View Answer on Stackoverflow

What is video timescale, timebase, or timestamp in ffmpeg?

Video Problem Overview

Video Solutions

Solution 1 - Video

Django Deprecation Warning or ImproperlyConfigured error - Passing a 3-tuple to django.conf.urls.include() is not supported

How to suppress the "Avoid using bundled version of Google Play services SDK" warning?

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