Recherche avancée

Sur d’autres sites (6391)

• Converting ffmpeg loudnorm first pass dcf summary report output to data.frame R

  23 décembre 2022, par Chris

  Following from operations on a video with ffmpeg, a loudnorm first pass report for purely audio files is produced

  


  names(aud_proc_df)
[1] "in_files" "proc_out" "filter"

cmds_loudness_report <- with(aud_proc_df, sprintf("ffmpeg -hide_banner -i %s -af loudnorm=I=-23:TP=-2:LRA=7:print_format=summary -f null /dev/null 2>&1 | tail -n 12 >> loudness_rpt_all.txt", in_files)) # linux specific notation
lapply(cmds_loudness_report, system)


  


  reading this as a .csv rather than .dcf

  


  loudness_df_csv <- read.csv('loudness_rpt_all.txt', header = FALSE, sep =':')
head(loudness_df_csv)
                 V1                  V2
1  Input Integrated          -24.7 LUFS
2   Input True Peak           -1.6 dBTP
3         Input LRA             17.9 LU
4   Input Threshold          -37.8 LUFS
5 Output Integrated          -23.4 LUFS
6  Output True Peak           -2.0 dBTP
#data
structure(list(V1 = c("Input Integrated", "Input True Peak", 
"Input LRA", "Input Threshold", "Output Integrated", "Output True Peak", 
"Output LRA", "Output Threshold", "Normalization Type", "Target Offset", 
"Input Integrated", "Input True Peak", "Input LRA", "Input Threshold", 
"Output Integrated", "Output True Peak", "Output LRA", "Output Threshold", 
"Normalization Type", "Target Offset"), V2 = c("    -24.7 LUFS", 
"      -1.6 dBTP", "            17.9 LU", "     -37.8 LUFS", 
"   -23.4 LUFS", "     -2.0 dBTP", "           14.8 LU", "    -36.2 LUFS", 
"   Dynamic", "        +0.4 LU", "    -23.9 LUFS", "      +0.2 dBTP", 
"            22.0 LU", "     -37.6 LUFS", "   -23.6 LUFS", "     -2.0 dBTP", 
"           21.9 LU", "    -37.0 LUFS", "   Dynamic", "        +0.6 LU"
)), row.names = c(NA, 20L), class = "data.frame")


  


  then, for column notation portability between win and linux systems

  


  df_names <- unique(loudness_df_csv$V1)
df_names2 <- gsub(' ', '_', df_names)


  


  and then make a data.frame

  


  loudnorm_rpt <- data.frame(loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[1])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[2])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[3])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[4])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[5])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[6])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[7])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[8])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[9])], loudness_df_csv$V2[which(loudness_df_csv$V1 == df_names[10])])
names(loudnorm_rpt) <- df_names2
rownames(loudnorm_rpt) <- c('A', 'B')


  


  Should I just wrap this in a function or is there a dcf to data.frame function that I've missed ?

  


• pyav / ffmpeg / libav select number of P-frames and B-frames

  27 mai 2021, par user1315621

  I am streaming from an rtsp source. It looks like half of the frames received are key frames. Is there a way to reduce this percentage and have an higher number of P-frames and B-frames ? If possible, I would like to increase the number of P-frames (not the one of B-frames).
I am using pyav which is a Python wrapper for libav (ffmpeg)

  


  Code :

  


  container = av.open(
    url, 'r',
    options={
        'rtsp_transport': 'tcp',
        'stimeout': '5000000',
        'max_delay': '5000000',
    }
)
stream = container.streams.video[0]
codec_context = stream.codec_context
codec_context.export_mvs = True
codec_context.gop_size = 25  

for packet in self.container.demux(video=0):
    for video_frame in packet.decode():
        print(video_frame.is_key_frame)


  


  Output :

  


  True
False
True
False
...


  


  Note 1 : I can't edit the source. I can just edit the code used to stream the video.

  


  Note 2 : same solution should apply to pyav, libavi and ffmpeg.

  


  Edit : it seems that B-frames are disabled : codec_context.has_b_frames is False

  


• ffmpeg OSError : [WinError 6] The handle is invalid when converted to exe

  13 septembre 2021, par thewayman

  I am trying to merge a video file with an audio file, using FFmpeg. It work fine when I am testing it but when I make an exe file via pyinstaller and including the FFmpeg.exe inside there is a peculiar error I am getting.

  


  


  OSError : [WinError 6] The handle is invalid

  


  


  This only happens when I set the FFmpeg run(quiet=True) but when I set the quiet=False everything works fine. The only problem is it shows the output window of FFmpeg.

  


  if getattr(sys, 'frozen', False):
   application_path = sys._MEIPASS
elif __file__:
   application_path = os.path.dirname(__file__)
ffmpegName = 'ffmpeg.exe'
ffmpegPath = os.path.join(application_path, ffmpegName)
video_stream = ffmpeg.input(file[0])
audio_stream = ffmpeg.input(file[1])
ffmpeg.output(audio_stream, video_stream, path).run(overwrite_output=True,
              cmd=ffmpegPath, quiet=True) #setting quiet=false everything works fine.


  


  Can anyone explain what's happening here ?
(Note the code is running in a different thread.)