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• AWS : Best way to generate a thumbnail for every frame of a s3 uploaded video

  4 janvier 2018, par danielfranca

  I need to process a video file, transcode it and generate a thumbnail for every frame.

  It should happen every time there’s a new video on a specific AWS bucket.

  I found out that AWS Lambda should be the best service for that

  However, it is not working as expected and I’ll explain why

  I’ve created a simple Python2.7 file using FFVideo
  It seems that this library doesn’t support Python3.

  It is a nice abstraction on top of ffmpeg

  To deploy the package I had run lld on the FFVideo shared object, and then copied everything to my project directory, as described in their documentation.
  Zipped it and upload to AWS Lambda

  Yet it doesn’t work, I keep getting errors as if the /usr/lib64/libstdc++ is missing, even after copied it to the projecct dir, also tried /usr/lib64 and /lib64

  Then as a second thought I wonder if just running ffmpeg wouldn’t be easier...
  So I just copied ffmpeg to the project dir and did a simple Python script to call it.

  Missing shared objects, ok, lld again and copied everything to the directory.

  Then AWS Lambda seems to be completely broken, I can’t save it anymore and it just says "Fix errors before saving"
  But no error message, nothing

  I even have attempted to write inline a simple code, but now AWS Lambda don’t even open the online editor.
  I also tried to remove all the shared objects I have added, returning to the original state, but still same generic error.
  Same thing if I just create a new lambda function with same old code.

  Doesn’t matter what I do it never even enable the Save button anymore.
  I thought it might be just some AWS unstability, but it been a while.

  I’ve looked to a similar project using Node
  and it doesn’t seem to include anything except ffmpeg

  My other idea is to use SQS to trigger a python script somewhere else to create the thumbnails

  Any idea how is the best approach for that ?

• FFMPEG H264 with custom overlay per frame

  4 octobre 2020, par La bla bla

  We have a stream that is stored in the cloud (Amazon S3) as individual H264 frames. The frames are stored as framexxxxxx.264, the numbering doesn't start from 0 but rather from some larger number, say 1000 (so, frame001000.264)

  


  The goal is to create a mp4 clip which is either timelapse or just faster for inspection and other checking (much faster, compressing around 3 hours of video down to < 20 minutes), this also requires we overlay the frame number (the filename) on the frame itself

  &#xA;

  At first I was creating a timelapse by pulling from S3 only the keyframes (i-frames ? still rather new to codecs & stuff) and overlaying the filename on them and saving as png (which probably isn't needed, but that's what I did) using (this command is used inside a python script)

  &#xA;

  ffmpeg -y -i {h264_name} -vf \"scale=1920:-1, 
drawtext=fontfile=/usr/share/fonts/truetype/ubuntu-font-family/Ubuntu-B.ttf:fontsize=34:text={txt}:fontcolor=white:x=50:y=50:bordercolor=black:borderw=2\" 
-c:a copy -pix_fmt yuv420p {basename}.png


  &#xA;

  after this I combined all the frames by using python to convert the lowest numbered frame to 0.png and incrementing (so it would be continuous, because I only used keyframes the numbers originally weren't sequential) and running

  &#xA;

  ffmpeg -y -f image2 -i %d.png -r {self.params.fps} -vcodec libx264 -crf {self.params.crf} -pix_fmt yuv420p {out_file}


  &#xA;

  and this worked great, but the difference between keyframes was too long to allow for proper inspection

  &#xA;

  so now for the question(s)

  &#xA;

  since I know frames that are not keyframes (p-frames ?) can't be used alone by ffmpeg, the method of overlaying the file name and converting it to png (or keep as h264, same thing) won't work, or at least, I couldn't find a way for it to work, maybe there's a way to specify a frame's keyframe ?, how can one overlay the filename (and not the frame number as shown here for example)

  &#xA;

  Also, is it possible to skip some p-frames between the keyframes ? (so if a keyframe is every 30 frames, we would take a keyframe, a frame 15 frames later, and next another keyframe)

  &#xA;

  I thought about using ffmpeg's pipe option to feed it with the files as they're being downloaded, but I'm not sure if I can specify drawtext this way

  &#xA;

  Also, if there's another alternative that can achieve that (at first I was converting to png, using python and OpenCV to add the filename and then merging the pngs to mp4, but then I found drawtext can do that in a single command so I used it)

  &#xA;

• Concatenate / Join MP4 files using ffmpeg and windows command line batch NOT LINUX

  10 septembre 2022, par julesverne

  I've written a batch script that attempts to take a generic introductory title video (MP4) that runs for 12 seconds and attaches it to the beginning of 4 other MP4 videos (same video but each has a different language audio track)

  &#xA;&#xA;

  According to ffmpeg syntax here : http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20concatenate%20%28join,%20merge%29%20media%20files the concat demuxer needs to be run from a text file that looks like this :

  &#xA;&#xA;

  # this is a comment
file '/path/to/file1'
file '/path/to/file2'
file '/path/to/file3'


  &#xA;&#xA;

  I believe everything in my script up until the point of joining the files appears to be working correctly. But I get this error :

  &#xA;&#xA;

  [concat @ 04177d00] Line 2: unknown keyword ''C:\Users\Joe\1May\session3\readyforfinalconversion\frenchfile.mp4'
filelistFrench.txt: Invalid data found when processing input
[concat @ 03b70a80] Line 2: unknown keyword ''C:\Users\Joe\1May\session3\readyforfinalconversion\spanishfile.mp4'
filelistSpanish.txt: Invalid data found when processing input
[concat @ 0211b960] Line 2: unknown keyword ''C:\Users\Joe\1May\session3\readyforfinalconversion\basquefile.mp4'
filelistBasque.txt: Invalid data found when processing input
[concat @ 03a20a80] Line 2: unknown keyword ''C:\Users\Joe\1May\session3\readyforfinalconversion\Englishfile.mp4'
filelistEnglish.txt: Invalid data found when processing input


  &#xA;&#xA;

  I believe the issue lies in the text file I'm creating. Please excuse my n00b ignorance, but sometimes new script makers like myself get confused about developer jargon and may take things literally.

  &#xA;&#xA;

  So when I look at that example text file they gave, am I correct in thinking THIS is what my text file should look like ?

  &#xA;&#xA;

  # this is a comment
Titlefile.mp4 'C:\Users\Joe\1May\session3\readyforfinalconversion\Titlefile.mp4'
Englishfile.mp4 'C:\Users\Joe\1May\session3\readyforfinalconversion\Englishfile.mp4'


  &#xA;&#xA;

  Again, am I being too literal ? are the quotations correct ? Are the slashes correct ? In the example they provide the slashes in the path are / instead of normal windows \ . I'll provide the entire script in case it helps.

  &#xA;&#xA;

  @echo off

setlocal EnableDelayedExpansion

rem Create an array of languages
set i=0
for %%a in (French Spanish Basque English) do (
   set /A i+=1
   set term[!i!]=%%a
)

rem Get the title video file name from user

set /p titlevideofilename=What is the title video file 

name?

rem create a path variable for the title video file

set pathtotitlevideo=%~dp0%titlevideofilename%

rem Get the names of the different language video files to append to the title video
rem create a path variable for each different language video files

for /L %%i in (1,1,4) do (
   set /p language[%%i]=what is the name of the !term

[%%i]! file you want to append after the title video?
   set pathtofile[%%i]=%~dp0!language[%%i]!
)

rem create data file for ffmpeg based on variable data

for /L %%i in (1,1,4) do (
    echo # this is a comment>>filelist!term[%

%i]!.txt
    echo file '%pathtotitlevideo%'>>filelist!term[%

%i]!.txt
    echo file '!pathtofile[%%i]!'>>filelist!term[%

%i]!.txt
)

cls

rem join files using ffmpeg concat option

for /L %%i in (1,1,4) do (
   c:\ffmpeg\ffmpeg\bin\ffmpeg.exe -loglevel error -f 

concat -i filelist!term[%%i]!.txt -c copy !language[%

%i]!.!term[%%i]!.withtitle.mp4
)

endlocal

:eof
exit


  &#xA;&#xA;

  EDIT
  &#xA;Thanks to @foxidrive making me look at the simplicity of it... it occurred to me that Apparently I wasn't being literal enough. I made these 3 changes and script works perfectly now&#xA;1 : "file" in there example literally meant the word "file" &#xA;2 : needed the use of single quotes not double quotes as it shows in there example. &#xA;3 : Used "\" instead of "/" as they have in there example.

  &#xA;&#xA;

  So NOW my code to create the text files looks like this :

  &#xA;&#xA;

  rem create data file for ffmpeg based on variable data

for /L %%i in (1,1,4) do (
    echo # this is a comment>>filelist!term[%

%i]!.txt
    echo file '%pathtotitlevideo%'>>filelist!term[%

%i]!.txt
    echo file '!pathtofile[%%i]!'>>filelist!term[%

%i]!.txt
)


  &#xA;&#xA;

  So NOW my text file looks like this :

  &#xA;&#xA;

  # this is a comment    
file 'C:\Users\Joe\1May\session3\readyforfinalconversion\Titlefile.mp4'
file 'C:\Users\Joe\1May\session3\readyforfinalconversion\Englishfile.mp4'


  &#xA;