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• external-downloader option not working as expected in youtube-dl

  31 mars 2021, par Coder_H

  I was trying to download specific timestamps from youtube using youtube-dl as mentioned as mentioned here in the comments

  


  youtube-dl -v "https://www.youtube.com/watch?v=1I-3vJSC-Vo" -x -k --external-downloader ffmpeg --external-downloader-args "-ss 0:30 -to 0:35"


  


  I got the following error :

  


  [youtube] 1I-3vJSC-Vo: Downloading webpage
[download] Destination: ONE MINUTE OF PURE SATISFACTION _ Compilation 1-1I-3vJSC-Vo.f398.mp4
ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
  configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/incl
ude/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable
-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libf
reetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-lib
openmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-lib
soxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack
 --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal -
-enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-l
ibopencv --enable-libx264 --enable-shared
  WARNING: library configuration mismatch
  avcodec     configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incd
ir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-lad
spa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig -
-enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg
--enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy
--enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enabl
e-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --ena
ble-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0
r --enable-libopencv --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libopencore_amrnb
--enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
  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
Option to (record or transcode stop time) cannot be applied to input url https://r7---sn-gwpa-civk.googlevideo.com/videoplayback?exp
ire=1617150322&ei=Em1jYPnzG7qr3LUP6eGr2A0&ip=2409%3A4043%3A609%3A4b92%3Ad9f7%3Ad14%3A44f9%3A8525&id=o-AALoNXBA9D9WAuCZn-2a9-JjLoqCOC
_11Lo7_9LdU7g0&itag=398&aitags=133%2C134%2C135%2C136%2C160%2C242%2C243%2C244%2C247%2C278%2C394%2C395%2C396%2C397%2C398&source=youtub
e&requiressl=yes&mh=05&mm=31%2C29&mn=sn-gwpa-civk%2Csn-gwpa-cvhd&ms=au%2Crdu&mv=m&mvi=7&pcm2cms=yes&pl=38&initcwndbps=148750&vprv=1&
mime=video%2Fmp4&ns=_3yx5zxNR1CYgHJamv8F-s4F&gir=yes&clen=4733883&dur=59.920&lmt=1578997687942906&mt=1617128452&fvip=7&keepalive=yes
&fexp=24001373%2C24007246&beids=9466588&c=WEB&txp=5431432&n=HoSSxcQKm_nNAUWgVTbz2&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2C
requiressl%2Cvprv%2Cmime%2Cns%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIhAN-MjT3t_kpgwkOrBiw8f-0q5iDINPxu4bjfgZS66nNGAiBOLta-kt_AuaqGH
D-hJiElj9oNALl35IsBseYOR5AU4A%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpcm2cms%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRAIgIf334bMxslsq
Lxpnn2BATGGV6GWoWoJQQuMMgQL-NaMCICojD-uZ1VkyxIOQrfOwlLAEJ-gCe1skejtRBk-oHejU -- you are trying to apply an input option to an output
 file or vice versa. Move this option before the file it belongs to.
Error parsing options for input file https://r7---sn-gwpa-civk.googlevideo.com/videoplayback?expire=1617150322&ei=Em1jYPnzG7qr3LUP6e
Gr2A0&ip=2409%3A4043%3A609%3A4b92%3Ad9f7%3Ad14%3A44f9%3A8525&id=o-AALoNXBA9D9WAuCZn-2a9-JjLoqCOC_11Lo7_9LdU7g0&itag=398&aitags=133%2
C134%2C135%2C136%2C160%2C242%2C243%2C244%2C247%2C278%2C394%2C395%2C396%2C397%2C398&source=youtube&requiressl=yes&mh=05&mm=31%2C29&mn
=sn-gwpa-civk%2Csn-gwpa-cvhd&ms=au%2Crdu&mv=m&mvi=7&pcm2cms=yes&pl=38&initcwndbps=148750&vprv=1&mime=video%2Fmp4&ns=_3yx5zxNR1CYgHJa
mv8F-s4F&gir=yes&clen=4733883&dur=59.920&lmt=1578997687942906&mt=1617128452&fvip=7&keepalive=yes&fexp=24001373%2C24007246&beids=9466
588&c=WEB&txp=5431432&n=HoSSxcQKm_nNAUWgVTbz2&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cns%2Cgir%
2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIhAN-MjT3t_kpgwkOrBiw8f-0q5iDINPxu4bjfgZS66nNGAiBOLta-kt_AuaqGHD-hJiElj9oNALl35IsBseYOR5AU4A%3D%3D&
lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpcm2cms%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRAIgIf334bMxslsqLxpnn2BATGGV6GWoWoJQQuMMgQL-NaMCICoj
D-uZ1VkyxIOQrfOwlLAEJ-gCe1skejtRBk-oHejU.
Error opening input files: Invalid argument


ERROR: ffmpeg exited with code 1



  


  Why am I facing this error despite using the same format as mentioned in the link ?

  


• FFMpeg/video4linux2,v4l2 : The v4l2 frame is 46448 bytes, but 153600 bytes are expected (Webcam capture not fast enough ?)

  30 août 2013, par user763410

  I am trying to capture webcam output in linux/ubuntu. I have a chicony webcam (lenovo laptop). I am running inside a VMWARE virtual machine. The capture is not proceeding beyond 10 seconds. can you please help.

  The command I used is :

  $ ffmpeg -y  -f video4linux2 -r 20 -s 160x120 -i /dev/video0 -acodec libfaac -ab 128k  /tmp/web.avi

  The most important message I am getting is :

  [video4linux2,v4l2 @ 0x9e43fa0] The v4l2 frame is 46448 bytes, but 153600 bytes are expected

  Complete message from ffmpeg :

  ffmpeg version N-55159-gf118b41 Copyright (c) 2000-2013 the FFmpeg developers
  
    built on Aug 18 2013 09:09:13 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
  
    configuration: --enable-libass --prefix=/opt/ffmpeg --enable-debug --enable-libfreetype
  
    libavutil      52. 40.100 / 52. 40.100
  
    libavcodec     55. 19.100 / 55. 19.100
  
    libavformat    55. 12.102 / 55. 12.102
  
    libavdevice    55.  3.100 / 55.  3.100
  
    libavfilter     3. 82.100 /  3. 82.100
  
    libswscale      2.  4.100 /  2.  4.100
  
    libswresample   0. 17.103 /  0. 17.103
  
  [video4linux2,v4l2 @ 0x9e43fa0] The V4L2 driver changed the video from 160x120 to 320x240
  
  [video4linux2,v4l2 @ 0x9e43fa0] The driver changed the time per frame from 1/20 to 1/15
  
  Input #0, video4linux2,v4l2, from '/dev/video0':
  
    Duration: N/A, start: 6424.338678, bitrate: 18432 kb/s
  
      Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 320x240, 18432 kb/s, 15 fps, 15 tbr, 1000k tbn, 1000k tbc
  
  Codec AVOption ab (set bitrate (in bits/s)) specified for output file #0 (/tmp/web.avi) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
  
  Output #0, avi, to '/tmp/web.avi':
  
    Metadata:
  
      ISFT            : Lavf55.12.102
  
      Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 320x240, q=2-31, 200 kb/s, 20 tbn, 20 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo -> mpeg4)
  
  Press [q] to stop, [?] for help
  
  [video4linux2,v4l2 @ 0x9e43fa0] The v4l2 frame is 46448 bytes, but 153600 bytes are expected
  
  /dev/video0: Invalid data found when processing input
  
  frame=   29 fps= 14 q=3.5 Lsize=      87kB time=00:00:01.45 bitrate= 490.0kbits/s    
  
  video:80kB audio:0kB subtitle:0 global headers:0kB muxing overhead 7.760075%
  
  [video4linux2,v4l2 @ 0x9e43fa0] Some buffers are still owned by the caller on close.

• Basic Video Palette Conversion

  20 août 2011, par Multimedia Mike — General, Python

  How do you take a 24-bit RGB image and convert it to an 8-bit paletted image for the purpose of compression using a codec that requires 8-bit input images ? Seems simple enough and that’s what I’m tackling in this post.

  Ask FFmpeg/Libav To Do It
  Ideally, FFmpeg / Libav should be able to handle this automatically. Indeed, FFmpeg used to be able to, at least at the time I wrote this post about ZMBV and was unhappy with FFmpeg’s default results. Somewhere along the line, FFmpeg and Libav lost the ability to do this. I suspect it got removed during some swscale refactoring.

  Still, there’s no telling if the old system would have computed palettes correctly for QuickTime files.

  Distance Approach
  When I started writing my SMC video encoder, I needed to convert RGB (from PNG files) to PAL8 colorspace. The path of least resistance was to match the pixels in the input image to the default 256-color palette that QuickTime assumes (and is hardcoded into FFmpeg/Libav).

  How to perform the matching ? Find the palette entry that is closest to a given input pixel, where "closest" is the minimum distance as computed by the usual distance formula (square root of the sum of the squares of the diffs of all the components).

  
  
  

  That means for each pixel in an image, check the pixel against 256 palette entries (early termination is possible if an acceptable threshold is met). As you might imagine, this can be a bit time-consuming. I wondered about a faster approach...

  Lookup Table
  I think this is the approach that FFmpeg used to use, but I went and derived it for myself after studying the default QuickTime palette table. There’s a pattern there— all of the RGB entries are comprised of combinations of 6 values — 0x00, 0x33, 0x66, 0x99, 0xCC, and 0xFF. If you mix and match these for red, green, and blue values, you come up with 6 * 6 * 6 = 216 different colors. This happens to be identical to the web-safe color palette.

  The first (0th) entry in the table is (FF, FF, FF), followed by (FF, FF, CC), (FF, FF, 99), and on down to (FF, FF, 00) when the green component gets knocked down and step and the next color is (FF, CC, FF). The first 36 palette entries in the table all have a red component of 0xFF. Thus, if an input RGB pixel has a red color closest to 0xFF, it must map to one of those first 36 entries.

  I created a table which maps indices 0..215 to values from 5..0. Each of the R, G, and B components of an input pixel are used to index into this table and derive 3 indices ri, gi, and bi. Finally, the index into the palette table is given by :

    index = ri * 36 + gi * 6 + bi
  

  For example, the pixel (0xFE, 0xFE, 0x01) would yield ri, gi, and bi values of 0, 0, and 5. Therefore :

    index = 0 * 36 + 0 * 6 + 5
  

  The palette index is 5, which maps to color (0xFF, 0xFF, 0x00).

  Validation
  So I was pretty pleased with myself for coming up with that. Now, ideally, swapping out one algorithm for another in my SMC encoder should yield identical results. That wasn’t the case, initially.

  One problem is that the regulation QuickTime palette actually has 40 more entries above and beyond the typical 216-entry color cube (rounding out the grand total of 256 colors). Thus, using the distance approach with the full default table provides for a little more accuracy.

  However, there still seems to be a problem. Let’s check our old standby, the Big Buck Bunny logo image :

  
  
  Distance approach using the full 256-color QuickTime default palette
  
  
  Distance approach using the 216-color palette
  
  
  Table lookup approach using the 216-color palette
  

  I can’t quite account for that big red splotch there. That’s the most notable difference between images 1 and 2 and the only visible difference between images 2 and 3.

  To prove to myself that the distance approach is equivalent to the table approach, I wrote a Python script to iterate through all possible RGB combinations and verify the equivalence. If you’re not up on your base 2 math, that’s 2²⁴ or 16,777,216 colors to run through. I used Python’s multiprocessing module to great effect and really maximized a Core i7 CPU with 8 hardware threads.

  So I’m confident that the palette conversion techniques are sound. The red spot is probably attributable to a bug in my WIP SMC encoder.

  Source Code
  Update August 23, 2011 : Here’s the Python code I used for proving equivalence between the 2 approaches. In terms of leveraging multiple CPUs, it’s possibly the best program I have written to date.

  PLAIN TEXT

  PYTHON :

  1. # !/usr/bin/python
  2.  
  3. from multiprocessing import Pool
  4.  
  5. palette = []
  6. pal8_table = []
  7.  
  8. def process_r(r) :
  9.  counts = []
  10.  
  11.  for i in xrange(216) :
  12.   counts.append(0)
  13.  
  14.  print "r = %d" % (r)
  15.  for g in xrange(256) :
  16.   for b in xrange(256) :
  17.    min_dsqrd = 0xFFFFFFFF
  18.    best_index = 0
  19.    for i in xrange(len(palette)) :
  20.     dr = palette[i][0] - r
  21.     dg = palette[i][1] - g
  22.     db = palette[i][2] - b
  23.     dsqrd = dr * dr + dg * dg + db * db
  24.     if dsqrd <min_dsqrd :
  25.      min_dsqrd = dsqrd
  26.      best_index = i
  27.    counts[best_index] += 1
  28.  
  29.    # check if the distance approach deviates from the table-based approach
  30.    i = best_index
  31.    r = palette[i][0]
  32.    g = palette[i][1]
  33.    b = palette[i][2]
  34.    ri = pal8_table[r]
  35.    gi = pal8_table[g]
  36.    bi = pal8_table[b]
  37.    table_index = ri * 36 + gi * 6 + bi ;
  38.    if table_index != best_index :
  39.     print "(0x%02X 0x%02X 0x%02X) : distance index = %d, table index = %d" % (r, g, b, best_index, table_index)
  40.  
  41.  return counts
  42.  
  43. if __name__ == ’__main__’ :
  44.  counts = []
  45.  for i in xrange(216) :
  46.   counts.append(0)
  47.  
  48.  # initialize reference palette
  49.  color_steps = [ 0xFF, 0xCC, 0x99, 0x66, 0x33, 0x00 ]
  50.  for r in color_steps :
  51.   for g in color_steps :
  52.    for b in color_steps :
  53.     palette.append([r, g, b])
  54.  
  55.  # initialize palette conversion table
  56.  for i in range(0, 26) :
  57.   pal8_table.append(5)
  58.  for i in range(26, 77) :
  59.   pal8_table.append(4)
  60.  for i in range(77, 128) :
  61.   pal8_table.append(3)
  62.  for i in range(128, 179) :
  63.   pal8_table.append(2)
  64.  for i in range(179, 230) :
  65.   pal8_table.append(1)
  66.  for i in range(230, 256) :
  67.   pal8_table.append(0)
  68.  
  69.  # create a pool of worker threads and break up the overall job
  70.  pool = Pool()
  71.  it = pool.imap_unordered(process_r, range(256))
  72.  try :
  73.   while 1 :
  74.    partial_counts = it.next()
  75.    for i in xrange(216) :
  76.     counts[i] += partial_counts[i]
  77.  except StopIteration :
  78.   pass
  79.  
  80.  print "index, count, red, green, blue"
  81.  for i in xrange(len(counts)) :
  82.   print "%d, %d, %d, %d, %d" % (i, counts[i], palette[i][0], palette[i][1], palette[i][2])