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• Upper limit on FFMPEG/libx264 frame sizes ?

  22 mars 2014, par Chaotic

  I'm trying to use FFMPEG to transcode a video with very large frames (4096 x 4096). It's a short video - just under two minutes, but the source video file is 15.8GB. (The video is an animation designed to be projected onto planetarium domes.)

  The source file is a Quicktime MOV containing uncompressed Photo-JPEG images (with audio, too). When I tell FFMPEG to transcode my MOV file into an MP4 file, it simply says :

  Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height

  Not very helpful, but yes, I've verified that all of the parameters are correct and/or defaults. In fact, if I change the requested output size to 2048x2048, then everything works just fine. That's why I suspect that there's an upper bound in the encoder.

  I am kerflummoxed. Any suggestions that result in a successful transcode will be greatly appreciated. (At this point I am also willing to consider alternatives to FFMPEG.)

  The Facts

  I run FFMPEG from a script :

  set srcFile=%1
  
  set dstFile=%srcFile:.mov=.mp4%
  
  
  
  ffmpeg -i %srcFile% -movflags faststart -q:a 0 -q:v 0 -pix_fmt yuv420p -sws_flags gauss -s 4096x4096 %dstFile%

  The Output

      ffmpeg version N-50911-g9efcfbe Copyright (c) 2000-2013 the FFmpeg developers
  
      built on Mar 13 2013 21:26:48 with gcc 4.7.2 (GCC)
  
      configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetype --enable-libgsm --enable-libilbc --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --ena
  
  ble-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
  
    libavutil      52. 19.100 / 52. 19.100
  
    libavcodec     55.  0.100 / 55.  0.100
  
    libavformat    55.  0.100 / 55.  0.100
  
    libavdevice    54.  4.100 / 54.  4.100
  
    libavfilter     3. 45.103 /  3. 45.103
  
    libswscale      2.  2.100 /  2.  2.100
  
    libswresample   0. 17.102 /  0. 17.102
  
    libpostproc    52.  2.100 / 52.  2.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'also-sprach-zarathustra-4k.mov':
  
    Metadata:
  
      major_brand     : qt
  
      minor_version   : 537199360
  
      compatible_brands: qt
  
      creation_time   : 2013-01-11 23:41:30
  
    Duration: 00:01:40.57, start: 0.000000, bitrate: 1357694 kb/s
  
      Stream #0:0(eng): Audio: pcm_s16be (twos / 0x736F7774), 44100 Hz, stereo, s16, 1411 kb/s
  
      Metadata:
  
        creation_time   : 2013-01-11 23:41:30
  
        handler_name    : Apple Alias Data Handler
  
      Stream #0:1(eng): Video: mjpeg (jpeg / 0x6765706A), yuvj420p, 4096x4096 [SAR 1:1 DAR 1:1], 1356281 kb/s, 30 fps, 30
  
  tbr, 3k tbn, 3k tbc
  
      Metadata:
  
        creation_time   : 2013-01-11 23:41:30
  
        handler_name    : Apple Alias Data Handler
  
  File 'also-sprach-zarathustra-4k.mp4' already exists. Overwrite ? [y/N] y
  
  using SAR=1/1
  
  [libx264 @ 003b9c80] frame MB size (256x256) > level limit (36864)
  
  [libx264 @ 003b9c80] DPB size (4 frames, 262144 mbs) > level limit (2 frames, 184320 mbs)
  
  [libx264 @ 003b9c80] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX AVX2 FMA3 LZCNT BMI1 BMI2
  
  x264 [error]: malloc of size 17305600 failed
  
  Output #0, mp4, to 'also-sprach-zarathustra-4k.mp4':
  
    Metadata:
  
      major_brand     : qt
  
      minor_version   : 537199360
  
      compatible_brands: qt
  
      Stream #0:0(eng): Video: h264, yuv420p, 4096x4096 [SAR 1:1 DAR 1:1], q=-1--1, 90k tbn, 30 tbc
  
      Metadata:
  
        creation_time   : 2013-01-11 23:41:30
  
        handler_name    : Apple Alias Data Handler
  
      Stream #0:1(eng): Audio: none, 44100 Hz, stereo, s16, 128 kb/s
  
      Metadata:
  
        creation_time   : 2013-01-11 23:41:30
  
        handler_name    : Apple Alias Data Handler
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (mjpeg -> libx264)
  
    Stream #0:0 -> #0:1 (pcm_s16be -> libvo_aacenc)
  
  Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height

  PS : Yes, for those playing at home, it is the theme to 2001 - A Space Odyssey. You can see a 1K YouTube version here : 2001 - A Fulldome Space Odyssey And yes, in a planetarium with a good sound system, it is absolutely EPIC.

• How to run a bat file when clicking a button in an electron + react application ?

  12 novembre 2020, par Артем

  I am using Windows 7
  
I want to write a windows app using electron + react.
  
The essence of the application is to run bat files.
  
Bat files will execute their script.
  
In this case, I have already written baht files, they work with the FFMPEG.
  
I like FFMPEG and I would like to make it easy to use on Windows with such an application.
  
At this stage, I have two folders Your_files and Result, next to these folders are ready-made baht files and ffmpeg.exe.
  

  


  

  1. In the folder Your_files I put the files to convert.
     

  


  2. I click on the desired baht file, it converts.
     

  


  3. I take the finished files from the Result folder.
     

  


  


  I would like to write a nice application now.
  
There will be one window with buttons in the CMD style - minimalism. On the buttons, the labels are similar (mp4 - mkv) and others.
  
I also plan to place two folders Your_files and Result next to the application.
  
The principle is the same, only here is a beautiful visual interface with buttons for the place of many baht files.
  
It will be easier to visually choose what you need.
  
The crux of the question : How to launch a baht file when you click on a button in the application ?
  Perhaps you have some ideas on how to implement this even better .. I welcome your suggestions with a detailed description.
  
------------------------
  
P.S. I originally planned the following... But I decided to abandon this implementation. ))
  
I recorded a cycle in a baht file.
  
The cycle was launched in the bat file mshta.exe with HTML layout (visual interface). lol
  
Received the value of a variable, which he entered in the visual interface of the mshta.exe window.
  
The variable returned to the loop and the baht file was executed.
  
But I don't think this is the best approach. Use a similar hybrid.
  
Take a look at this for fun.
  

  


  &#xA;&#xA;&#xA;&#xA;&#xA;&#xA;    &#xA;    &#xA;    &#xA;    &#xA;    <code class="echappe-js">&lt;script type=&quot;text/javascript&quot;&gt;&amp;#xA;        function myFunction() {&amp;#xA;            var copyText = document.getElementById(&quot;myInput&quot;);&amp;#xA;            copyText.select();&amp;#xA;            document.execCommand(&quot;copy&quot;);&amp;#xA;        }&amp;#xA;    &lt;/script&gt;&#xA;&#xA;&#xA;&#xA;    &lt;script language=&amp;#x27;javascript&amp;#x27;&gt;&amp;#xA;        window.resizeTo(800, 300);&amp;#xA;&amp;#xA;        function entperPressed(e) {&amp;#xA;            if (e.keyCode == 13) {&amp;#xA;                pipePass();&amp;#xA;            }&amp;#xA;        }&amp;#xA;&amp;#xA;        function pipePass() {&amp;#xA;            var pass = document.getElementById(&amp;#x27;pass&amp;#x27;).value;&amp;#xA;            var fso = new ActiveXObject(&amp;#x27;Scripting.FileSystemObject&amp;#x27;).GetStandardStream(1);&amp;#xA;            close(fso.Write(pass));&amp;#xA;&amp;#xA;        }&amp;#xA;    &lt;/script&gt;&#xA;    
  Enter time of frame. Введите время кадра
  &#xA;    
  
  hh:mm:ss.mss – 00:00:00.000
  &#xA;
  (colons can be omitted as well as milliseconds)
  &#xA;
  (двоеточия при вводе можно опустить как и миллисекунды)
  &#xA;
  &#xA;        &#xA;        Okey
  &#xA;
  
  &#xA;
  &#xA;        Copy
  &#xA;        &#xA;
  
  &#xA;&#xA;&#xA;&#xA;
  

  


  Photo

  


• CD-R Read Speed Experiments

  21 mai 2011, par Multimedia Mike — Science Projects, Sega Dreamcast

  I want to know how fast I can really read data from a CD-R. Pursuant to my previous musings on this subject, I was informed that it is inadequate to profile reading just any file from a CD-R since data might be read faster or slower depending on whether the data is closer to the inside or the outside of the disc.

  Conclusion / Executive Summary
  It is 100% true that reading data from the outside of a CD-R is faster than reading data from the inside. Read on if you care to know the details of how I arrived at this conclusion, and to find out just how much speed advantage there is to reading from the outside rather than the inside.

  Science Project Outline

  • Create some sample CD-Rs with various properties
  • Get a variety of optical drives
  • Write a custom program that profiles the read speed

  Creating The Test Media
  It’s my understanding that not all CD-Rs are created equal. Fortunately, I have 3 spindles of media handy : Some plain-looking Memorex discs, some rather flamboyant Maxell discs, and those 80mm TDK discs :

  
  
  

  My approach for burning is to create a single file to be burned into a standard ISO-9660 filesystem. The size of the file will be the advertised length of the CD-R minus 1 megabyte for overhead— so, 699 MB for the 120mm discs, 209 MB for the 80mm disc. The file will contain a repeating sequence of 0..0xFF bytes.

  Profiling
  I don’t want to leave this to the vagaries of any filesystem handling layer so I will conduct this experiment at the sector level. Profiling program outline :

  • Read the CD-ROM TOC and get the number of sectors that comprise the data track
  • Profile reading the first 20 MB of sectors
  • Profile reading 20 MB of sectors in the middle of the track
  • Profile reading the last 20 MB of sectors

  Unfortunately, I couldn’t figure out the raw sector reading on modern Linux incarnations (which is annoying since I remember it being pretty straightforward years ago). So I left it to the filesystem after all. New algorithm :

  • Open the single, large file on the CD-R and query the file length
  • Profile reading the first 20 MB of data, 512 kbytes at a time
  • Profile reading 20 MB of sectors in the middle of the track (starting from filesize / 2 - 10 MB), 512 kbytes at a time
  • Profile reading the last 20 MB of sectors (starting from filesize - 20MB), 512 kbytes at a time

  Empirical Data
  I tested the program in Linux using an LG Slim external multi-drive (seen at the top of the pile in this post) and one of my Sega Dreamcast units. I gathered the median value of 3 runs for each area (inner, middle, and outer). I also conducted a buffer flush in between Linux runs (as root : 'sync; echo 3 > /proc/sys/vm/drop_caches').

  LG Slim external multi-drive (reading from inner, middle, and outer areas in kbytes/sec) :

  • TDK-80mm : 721, 897, 1048
  • Memorex-120mm : 1601, 2805, 3623
  • Maxell-120mm : 1660, 2806, 3624

  So the 120mm discs can range from about 10.5X all the way up to a full 24X on this drive. For whatever reason, the 80mm disc fares a bit worse — even at the inner track — with a range of 4.8X - 7X.

  Sega Dreamcast (reading from inner, middle, and outer areas in kbytes/sec) :

  • TDK-80mm : 502, 632, 749
  • Memorex-120mm : 499, 889, 1143
  • Maxell-120mm : 500, 890, 1156

  It’s interesting that the 80mm disc performed comparably to the 120mm discs in the Dreamcast, in contrast to the LG Slim drive. Also, the results are consistent with my previous profiling experiments, which largely only touched the inner area. The read speeds range from 3.3X - 7.7X. The middle of a 120mm disc reads at about 6X.

  Implications
  A few thoughts regarding these results :

  • Since the very definition of 1X is the minimum speed necessary to stream data from an audio CD, then presumably, original 1X CD-ROM drives would have needed to be capable of reading 1X from the inner area. I wonder what the max read speed at the outer edges was ? It’s unlikely I would be able to get a 1X drive working easily in this day and age since the earliest CD-ROM drives required custom controllers.
  • I think 24X is the max rated read speed for CD-Rs, at least for this drive. This implies that the marketing literature only cites the best possible numbers. I guess this is no surprise, similar to how monitors and TVs have always been measured by their diagonal dimension.
  • Given this data, how do you engineer an ISO-9660 filesystem image so that the timing-sensitive multimedia files live on the outermost track ? In the Dreamcast case, if you can guarantee your FMV files will live somewhere between the middle and the end of the disc, you should be able to count on a bitrate of at least 900 kbytes/sec.

  Source Code
  Here is the program I wrote for profiling. Note that the filename is hardcoded (#define FILENAME). Compiling for Linux is a simple 'gcc -Wall profile-cdr.c -o profile-cdr'. Compiling for Dreamcast is performed in the standard KallistiOS manner (people skilled in the art already know what they need to know) ; the only variation is to compile with the '-D_arch_dreamcast' flag, which the default KOS environment adds anyway.

  PLAIN TEXT

  C :

  1. #ifdef _arch_dreamcast
  2.   #include <kos .h>
  3.  
  4.   /* map I/O functions to their KOS equivalents */
  5.   #define open fs_open
  6.   #define lseek fs_seek
  7.   #define read fs_read
  8.   #define close fs_close
  9.  
  10.   #define FILENAME "/cd/bigfile"
  11. #else
  12.   #include <stdio .h>
  13.   #include <sys /types.h>
  14.   #include </sys><sys /stat.h>
  15.   #include </sys><sys /time.h>
  16.   #include <fcntl .h>
  17.   #include <unistd .h>
  18.  
  19.   #define FILENAME "/media/Full disc/bigfile"
  20. #endif
  21.  
  22. /* Get a current absolute millisecond count ; it doesn’t have to be in
  23. * reference to anything special. */
  24. unsigned int get_current_milliseconds()
  25. {
  26. #ifdef _arch_dreamcast
  27.   return timer_ms_gettime64() ;
  28. #else
  29.   struct timeval tv ;
  30.   gettimeofday(&tv, NULL) ;
  31.   return tv.tv_sec * 1000 + tv.tv_usec / 1000 ;
  32. #endif
  33. }
  34.  
  35. #define READ_SIZE (20 * 1024 * 1024)
  36. #define READ_BUFFER_SIZE (512 * 1024)
  37.  
  38. int main()
  39. {
  40.   int i, j ;
  41.   int fd ;
  42.   char read_buffer[READ_BUFFER_SIZE] ;
  43.   off_t filesize ;
  44.   unsigned int start_time, end_time ;
  45.  
  46.   fd = open(FILENAME, O_RDONLY) ;
  47.   if (fd == -1)
  48.   {
  49.     printf("could not open %s\n", FILENAME) ;
  50.     return 1 ;
  51.   }
  52.   filesize = lseek(fd, 0, SEEK_END) ;
  53.  
  54.   for (i = 0 ; i <3 ; i++)
  55.   {
  56.     if (i == 0)
  57.     {
  58.       printf("reading inner 20 MB...\n") ;
  59.       lseek(fd, 0, SEEK_SET) ;
  60.     }
  61.     else if (i == 1)
  62.     {
  63.       printf("reading middle 20 MB...\n") ;
  64.       lseek(fd, (filesize / 2) - (READ_SIZE / 2), SEEK_SET) ;
  65.     }
  66.     else
  67.     {
  68.       printf("reading outer 20 MB...\n") ;
  69.       lseek(fd, filesize - READ_SIZE, SEEK_SET) ;
  70.     }
  71.     /* read 20 MB ; 40 chunks of 1/2 MB */
  72.     start_time = get_current_milliseconds() ;
  73.     for (j = 0 ; j <(READ_SIZE / READ_BUFFER_SIZE) ; j++)
  74.       if (read(fd, read_buffer, READ_BUFFER_SIZE) != READ_BUFFER_SIZE)
  75.       {
  76.         printf("read error\n") ;
  77.         break ;
  78.       }
  79.     end_time = get_current_milliseconds() ;
  80.     printf("%d - %d = %d ms => %d kbytes/sec\n",
  81.       end_time, start_time, end_time - start_time,
  82.       READ_SIZE / (end_time - start_time)) ;
  83.   }
  84.  
  85.   close(fd) ;
  86.  
  87.   return 0 ;
  88. }