Recherche avancée

Sur d’autres sites (7400)

• ffmpeg how to determine the size of the image and stretch the video to fit it ?

  11 décembre 2020, par Артем

  I want to automatically detect the size of the image and stretch the video to fit it.
  
I have images of different sizes.
  
There is a video with a green background one size.
  
I remove the chromakey and overlay the image.
  
But I have a problem, my video is of a different size.
  
Me need to automatically expand or contract it to the size of the image.
  

  


  @echo off
setlocal EnableDelayedExpansion
color a
set a=Your_files\*.jpg
set aa=Your_files\*.mp4
set b="Result\%%~na.mp4"
set c=ffmpeg
set f=-filter_complex "[1:v]chromakey=0x00D700:0.1:0.3[ckout];[0:v][ckout]overlay=(W-w)/1:(H-h)/1[o]" -map [o] -map 1:a -c:a copy
for %%s in (%aa%) do !set aud="%%s"!
for %%a in (%a%) do (%c% -y -i "%%a" -i %aud% %f% %b%)
exit


  


  Help me please
  

  


  Bad idea.. Images can be of different formats. (there will be distortion)
  

  


  


  Me only one thing comes to my mind.
  
Separately resize the image.
  
Separately resize the video.
  
And then work with them...
  

  


  


• How to determine the proper HTML5 video codec attribute for an AV1 file based on the FFMpeg encoding command or output ?

  20 décembre 2020, par Slbox

  We have some files encoded in AV1, but we recently noticed that Chrome mobile fails to play the files - but it doesn't fall back to an encoding it can use - it just puts the unplayable AV1 file in there. I'm hoping that if we add a codec attribute we can remedy this - but I'm not sure how to determine the codec for these AV1 files.

  


  I've come across this documentation on MDN, but I'm not sure how I would determine the proper codec from that. It starts off simple enough, but some of the values further down, I have no idea what the right value would be.

  


  Opening the file in VLC player only shows this very limited information about the codec :

  


  

  


  The output of MediaInfo is :

  


  General
Complete name                            : demo-av1.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/mp41)
File size                                : 291 KiB
Duration                                 : 1 min 40 s
Overall bit rate                         : 23.7 kb/s
Writing application                      : Lavf58.43.100

Video
ID                                       : 1
Format                                   : AV1
Format/Info                              : AOMedia Video 1
Format profile                           : High@L3.0
Codec ID                                 : av01
Duration                                 : 1 min 40 s
Bit rate                                 : 22.9 kb/s
Width                                    : 984 pixels
Height                                   : 670 pixels
Display aspect ratio                     : 3:2
Frame rate mode                          : Constant / Constant
Frame rate                               : 24.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:4:4
Bit depth                                : 8 bits
Scan type                                : Progressive / Progressive
Bits/(Pixel*Frame)                       : 0.001
Stream size                              : 281 KiB (96%)
Color range                              : Limited
Codec configuration box                  : av1C / av1C


  


  The command to create the files and the output of FFMpeg is like so :

  


  
ffmpeg -y -i "D:\RAW VIDEO\Demos\demo.avi" -ss 00:00:00  -c:v libaom-av1 -pix_fmt yuv444p -minrate 500 -b:v 48k -maxrate 1000k -strict experimental -movflags +faststart -f mp4 NUL && ffmpeg -y -i "D:\RAW VIDEO\Demos\demo.avi" -ss 00:00:00  -c:v libaom-av1 -pix_fmt yuv444p -minrate 500 -b:v 48k -maxrate 1000k -strict experimental -movflags +faststart -pass 2 "D:\RAW VIDEO\Demos\converted\demo-av1.mp4"
ffmpeg version git-2020-05-22-38490cb Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.3.1 (GCC) 20200513

  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --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-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 46.100 / 56. 46.100
  libavcodec     58. 86.101 / 58. 86.101
  libavformat    58. 43.100 / 58. 43.100
  libavdevice    58.  9.103 / 58.  9.103
  libavfilter     7. 82.100 /  7. 82.100
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100

Input #0, avi, from 'D:\RAW VIDEO\Demos\demo.avi':
  Metadata:
    encoder         : Lavf58.29.100
  Duration:
00:00:23.43, start: 0.000000, bitrate: 19719 kb/s
    Stream #0:0: Video: huffyuv (HFYU / 0x55594648), bgr0, 420x240, 19739 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc

Stream mapping:
  Stream #0:0 -> #0:0 (huffyuv (native) -> av1 (libaom-av1))

Press [q] to stop, [?] for help

[libaom-av1 @ 00000000003fb3c0] v1.0.0

Output #0, mp4, to 'NUL':
  Metadata:
    encoder         : Lavf58.43.100

    Stream #0:0: Video: av1 (libaom-av1) (av01 / 0x31307661), yuv444p, 420x240, q=-1--1, 48 kb/s, 30 fps, 15360 tbn, 30 tbc
    Metadata:
      encoder         : Lavc58.86.101 libaom-av1
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A




  


• Determine if FFmpeg ran successfully [duplicate]

  31 janvier 2021, par Spedwards

  I have a script I've been using to transcode videos from h264 to h265 in order to preserve space. A lot of manual effort is required to go through and delete the larger files (not always the h264 version). If I was able to determine whether or not FFmpeg finished successfully, I'd be able to save myself a lot of time.

  


  I'll cut out a lot of stuff that's not relevant to the question but below you'll find my script.

  


  function transcode() {
    output=$(echo "$1" | sed -r 's/^(.+)(\.\w{3})$/\1.h265\2/g');
    ffmpeg # a lot of options (including -hide_banner and -loglevel panic)
    echo "$output";
}

RESET=$(tput sgr0);
YELLOW=$(tput setaf 3);
CYAN=$(tput setaf 6);

for f in *.mp4; do
    original=$(stat -c %s "$f");
    echo "${YELLOW}Transcoding file: ${CYAN}$f${RESET}";
    new_file_name=$(transcode "$f");
    new_file_size=$(stat -c %s "$new_file_name");
    if [[ "$new_file_size" -gt "$original" ]]; then
        rm "$new_file_name";
    fi
    echo "";
done;


  


  Ideally, I'd like to delete the original source file if the transcoded file is smaller and FFmpeg ran successfully. Unfortunately due to various reasons FFmpeg can fail while transcoding.

  


  I have seen a few questions asking similar stuff but implementing it is just going over my head. I can't really be creating text files with the output either (though I guess that can be cleaned up as it goes).

  


  Any help would be greatly appreciated.