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• Museum of Multimedia Software, Part 1

  14 août 2010, par Multimedia Mike — Software Museum

  Many years ago, I found a boneyard of old software, much of it related to the creation and processing of multimedia. I was permitted to liberate anything of my choosing from this cache. This is the same pile where I found this Apple QuickTime format spec as well as this perfect form factor floppy disc box. So I have been sitting on the stuff for awhile.

  I thought I might get the chance to study it a bit more closely one day. But now I’m interested in getting rid of it. Before I do, it’s more or less traditional for me to photograph it and post it on one blog or another. Also, if you know of any software collection groups who would be interested in taking this stuff off my hands, do let me know.

  As usual, click a picture for a much larger image.

  Paracomp FilmMaker
  This is easily the most distinctive piece in this collection and it’s easy to see why— the software is packaged in a film cannister. Still sealed, and I don’t have a good reason to open it now.

  
  
  

  "The Professional Animation/Presentation Program for the Macintosh." No copyright date on the packaging, though the front does mention a 1990 award. System requirements : Mac OS 6.0.5, 5 MB RAM, 32-bit QuickDraw, math coprocessor.

  Strata VideoShop
  Version 4.5 (and not for resale), still shrink-wrapped. "The Digital Video Editor for Creative Professionals."

  
  
  

  System requirements : PowerMac with 5 MB RAM (8 MB recommended), Mac OS 7.5.

  BeatWare e-Picture
  "The Professional’s Choice for Designing Animated Web Graphics." Claims a best of show award for 1999 MacWorld New York Expo.

  
  
  

  System requirements : PowerMac with Mac OS 8, 32MB RAM, 10 MB of HD space and a 256-color adapter.

  BeatWare eZ-Motion
  Another offering from BeatWare. "The fastest and easiest way to create animations and graphics for the Web."

  
  
  

  This one is for either Mac or Windows. 32 MB RAM and 25 MB HD space required. Works with Mac OS 8.5, 8.6, or 9.0, or Windows 98, NT, or 2000.

  Much more to come...

• FFMPEG Steam Stream stop after a few min

  24 novembre 2022, par Fabian Boulegue

  I try set a video stream to STREAM via FFMPEG so far everything works fine but after a few min it just seem to timeout (at last the stream stops but ffmpeg still send everything)

  



  Here is the ffmpeg string

  



  OUTRES="1920x1080"
GOP="60"
GOPMIN="15"
THREADS="4"
CBR="2500k"
QUALITY="ultrafast"
VIDEO="rescue.mp4"
STREAM_KEY="steam_62879128_f5xxxxxxxca5b1c"
SERVER="rtmp://ingest-01-fra1.broadcast.steamcontent.com/app/"

ffmpeg -stream_loop -1 -i $VIDEO -f flv \
-vcodec libx264 -g  $GOP -keyint_min $GOPMIN -b:v $CBR -minrate $CBR -maxrate $CBR -pix_fmt yuv420p \
-s $OUTRES -flvflags no_duration_filesize -preset $QUALITY -tune film -acodec aac -threads $THREADS -strict normal \
-bufsize $CBR "$SERVER$STREAM_KEY"


  



  this is the ffmpeg output

  



    ffmpeg version 3.4.6-0ubuntu0.18.04.1 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.3.0-16ubuntu3)
  configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/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-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 --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-libopencv --enable-libx264 --enable-shared
  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
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'rescue.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.83.100
  Duration: 00:44:48.08, start: 0.000000, bitrate: 2250 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 2114 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 127 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 0x55a3ddc7e520] using SAR=1/1
[libx264 @ 0x55a3ddc7e520] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x55a3ddc7e520] profile Constrained Baseline, level 4.0
[libx264 @ 0x55a3ddc7e520] 264 - core 152 r2854 e9a5903 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:-1:-1 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.15 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=4 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=60 keyint_min=15 scenecut=0 intra_refresh=0 rc_lookahead=0 rc=cbr mbtree=0 bitrate=2500 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=2500 vbv_bufsize=2500 nal_hrd=none filler=0 ip_ratio=1.40 aq=0
Output #0, flv, to 'rtmp://ingest-01-fra1.broadcast.steamcontent.com/app/steam_62879128_f5999013aeca5b1c':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.83.100
    Stream #0:0(und): Video: h264 (libx264) ([7][0][0][0] / 0x0007), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=-1--1, 2500 kb/s, 30 fps, 1k tbn, 30 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc57.107.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 2500000/0/2500000 buffer size: 2500000 vbv_delay: -1
    Stream #0:1(eng): Audio: aac (LC) ([10][0][0][0] / 0x000A), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      encoder         : Lavc57.107.100 aac
frame=  479 fps= 74 q=-1.0 Lsize=    4669kB time=00:00:16.13 bitrate=2370.2kbits/s speed=2.49x


  


• More Cinepak Madness

  20 octobre 2011, par Multimedia Mike — Codec Technology

  Fellow digital archaeologist Clone2727 found a possible fifth variant of the Cinepak video codec. He asked me if I cared to investigate the sample. I assured him I wouldn’t be able to die a happy multimedia nerd unless I have cataloged all possible Cinepak variants known to exist in the wild. I’m sure there are chemistry nerds out there who are ecstatic when another element is added to the periodic table. Well, that’s me, except with weird multimedia formats.

  Background
  Cinepak is a video codec that saw widespread use in the early days of digital multimedia. To date, we have cataloged 4 variants of Cinepak in the wild. This distinction is useful when trying to write and maintain an all-in-one decoder. The variants are :

  1. The standard type : Most Cinepak data falls into this category. It decodes to a modified/simplified YUV 4:2:0 planar colorspace and is often seen in AVI and QuickTime/MOV files.
  2. 8-bit greyscale : Essentially the same as the standard type but with only a Y plane. This has only been identified in AVI files and is distinguished by the file header’s video bits/pixel field being set to 8 instead of 24.
  3. 8-bit paletted : Again, this is identified by the video header specifying 8 bits/pixel for a Cinepak stream. There is essentially only a Y plane in the data, however, each 8-bit value is a palette index. The palette is transported along with the video header. To date, only one known sample of this format has even been spotted in the wild, and it’s classified as NSFW. It is also a QuickTime/MOV file.
  4. Sega/FILM CPK data : Sega Saturn games often used CPK files which stored a variant of Cinepak that, while very close the standard Cinepak, couldn’t be decoded with standard decoder components.

  So, a flexible Cinepak decoder has to identify if the file’s video header specified 8 bits/pixel. How does it distinguish between greyscale and paletted ? If a file is paletted, a custom palette should have been included with the video header. Thus, if video bits/pixel is 8 and a palette is present, use paletted ; else, use greyscale. Beyond that, the Cinepak decoder has a heuristic to determine how to handle the standard type of data, which might deviate slightly if it comes from a Sega CPK file.

  The Fifth Variant ?
  Now, regarding this fifth variant– the reason this issue came up is because of that aforementioned heuristic. Basically, a Cinepak chunk is supposed to store the length of the entire chunk in its header. The data from a Sega CPK file plays fast and loose with this chunk size and the discrepancy makes it easy to determine if the data requires special handling. However, a handful of files discovered on a Macintosh game called “The Journeyman Project : Pegasus Prime” have chunk lengths which are sometimes in disagreement with the lengths reported in the containing QuickTime file’s stsz atom. This trips the heuristic and tries to apply the CPK rules against Cinepak data which, aside from the weird chunk length, is perfectly compliant.

  Here are the first few chunk sizes, as reported by the file header (stsz atom) and the chunk :

  size from stsz = 7880 (0x1EC8) ; from header = 3940 (0xF64)
  size from stsz = 3940 (0xF64) ; from header = 3940 (0xF64)
  size from stsz = 15792 (0x3DB0) ; from header = 3948 (0xF6C)
  size from stsz = 11844 (0x2E44) ; from header = 3948 (0xF6C)
  

  Hey, there’s a pattern here. If they don’t match, then the stsz size is an even multiple of the chunk size (2x, 3x, or 4x in my observation). I suppose I could revise the heuristic to state that if the stsz size is 2x, 3x, 4x, or equal to the chunk header, qualify it as compliant Cinepak data.

  Of course it feels impure, but software engineering is rarely about programmatic purity. A decade of special cases in the FFmpeg / Libav codebases are a testament to that.

  What’s A Variant ?
  Suddenly, I find myself contemplating what truly constitutes a variant. Maybe this was just a broken encoder program making these files ? And for that, I assign it the designation of distinct variation, like some sort of special, unique showflake ?

  Then again, I documented Magic Carpet FLIC as being a distinct variant of the broader FLIC format (which has an enormous number of variants as well).