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• 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).

• ffmpeg how to add mkv to formats

  30 décembre 2015, par Mahmoud Saad

  hello after installing ffmpeg in my linux server with centos 6 after searching google i run ffmpeg -formats so i need to add mkv i know i will need to recompile ffmpeg but i do not know how to do it
  thank you

  File formats:
  
   D. = Demuxing supported
  
   .E = Muxing supported
  
   --
  
    E 3g2             3GP2 format
  
    E 3gp             3GP format
  
   D  4xm             4X Technologies format
  
   D  IFF             IFF format
  
   D  ISS             Funcom ISS format
  
   D  MTV             MTV format
  
   DE RoQ             raw id RoQ format
  
   D  aac             raw ADTS AAC
  
   DE ac3             raw AC-3
  
    E adts            ADTS AAC
  
   D  aea             MD STUDIO audio
  
   DE aiff            Audio IFF
  
   DE alaw            PCM A-law format
  
   DE alsa            ALSA audio output
  
   DE amr             3GPP AMR file format
  
   D  anm             Deluxe Paint Animation
  
   D  apc             CRYO APC format
  
   D  ape             Monkey's Audio
  
   DE asf             ASF format
  
    E asf_stream      ASF format
  
   DE ass             SSA/ASS format
  
   DE au              SUN AU format
  
   DE avi             AVI format
  
    E avm2            Flash 9 (AVM2) format
  
   D  avs             AVS format
  
   D  bethsoftvid     Bethesda Softworks VID format
  
   D  bfi             Brute Force & Ignorance
  
   D  bink            Bink
  
   D  c93             Interplay C93
  
   D  caf             Apple Core Audio Format
  
   D  cavsvideo       raw Chinese AVS video
  
   D  cdg             CD Graphics Format
  
    E crc             CRC testing format
  
   DE daud            D-Cinema audio format
  
   DE dirac           raw Dirac
  
   DE dnxhd           raw DNxHD (SMPTE VC-3)
  
   D  dsicin          Delphine Software International CIN format
  
   DE dts             raw DTS
  
   DE dv              DV video format
  
   D  dv1394          DV1394 A/V grab
  
    E dvd             MPEG-2 PS format (DVD VOB)
  
   D  dxa             DXA
  
   D  ea              Electronic Arts Multimedia Format
  
   D  ea_cdata        Electronic Arts cdata
  
   DE eac3            raw E-AC-3
  
   DE f32be           PCM 32 bit floating-point big-endian format
  
   DE f32le           PCM 32 bit floating-point little-endian format
  
   DE f64be           PCM 64 bit floating-point big-endian format
  
   DE f64le           PCM 64 bit floating-point little-endian format
  
   DE ffm             FFM (FFserver live feed) format
  
   D  film_cpk        Sega FILM/CPK format
  
   DE filmstrip       Adobe Filmstrip
  
   DE flac            raw FLAC
  
   D  flic            FLI/FLC/FLX animation format
  
   DE flv             FLV format
  
    E framecrc        framecrc testing format
  
    E gif             GIF Animation
  
   D  gsm             raw GSM
  
   DE gxf             GXF format
  
   DE h261            raw H.261
  
   DE h263            raw H.263
  
   DE h264            raw H.264 video format
  
   D  idcin           id Cinematic format
  
   DE image2          image2 sequence
  
   DE image2pipe      piped image2 sequence
  
   D  ingenient       raw Ingenient MJPEG
  
   D  ipmovie         Interplay MVE format
  
    E ipod            iPod H.264 MP4 format
  
   D  iv8             A format generated by IndigoVision 8000 video server
  
   D  libdc1394       dc1394 v.2 A/V grab
  
   D  lmlm4           lmlm4 raw format
  
   DE m4v             raw MPEG-4 video format
  
   DE matroska        Matroska file format
  
   DE mjpeg           raw MJPEG video
  
   DE mlp             raw MLP
  
   D  mm              American Laser Games MM format
  
   DE mmf             Yamaha SMAF
  
    E mov             MOV format
  
   D  mov,mp4,m4a,3gp,3g2,mj2 QuickTime/MPEG-4/Motion JPEG 2000 format
  
    E mp2             MPEG audio layer 2
  
   DE mp3             MPEG audio layer 3
  
    E mp4             MP4 format
  
   D  mpc             Musepack
  
   D  mpc8            Musepack SV8
  
   DE mpeg            MPEG-1 System format
  
    E mpeg1video      raw MPEG-1 video
  
    E mpeg2video      raw MPEG-2 video
  
   DE mpegts          MPEG-2 transport stream format
  
   D  mpegtsraw       MPEG-2 raw transport stream format
  
   D  mpegvideo       raw MPEG video
  
    E mpjpeg          MIME multipart JPEG format
  
   D  msnwctcp        MSN TCP Webcam stream
  
   DE mulaw           PCM mu-law format
  
   D  mvi             Motion Pixels MVI format
  
   DE mxf             Material eXchange Format
  
    E mxf_d10         Material eXchange Format, D-10 Mapping
  
   D  nc              NC camera feed format
  
   D  nsv             Nullsoft Streaming Video
  
    E null            raw null video format
  
   DE nut             NUT format
  
   D  nuv             NuppelVideo format
  
   DE ogg             Ogg
  
   D  oma             Sony OpenMG audio
  
   DE oss             Open Sound System playback
  
    E psp             PSP MP4 format
  
   D  psxstr          Sony Playstation STR format
  
   D  pva             TechnoTrend PVA file and stream format
  
   D  qcp             QCP format
  
   D  r3d             REDCODE R3D format
  
   DE rawvideo        raw video format
  
    E rcv             VC-1 test bitstream
  
   D  rl2             RL2 format
  
   DE rm              RealMedia format
  
   D  rpl             RPL/ARMovie format
  
    E rtp             RTP output format
  
   DE rtsp            RTSP output format
  
   DE s16be           PCM signed 16 bit big-endian format
  
   DE s16le           PCM signed 16 bit little-endian format
  
   DE s24be           PCM signed 24 bit big-endian format
  
   DE s24le           PCM signed 24 bit little-endian format
  
   DE s32be           PCM signed 32 bit big-endian format
  
   DE s32le           PCM signed 32 bit little-endian format
  
   DE s8              PCM signed 8 bit format
  
   D  sdp             SDP
  
   D  shn             raw Shorten
  
   D  siff            Beam Software SIFF
  
   D  smk             Smacker video
  
   D  sol             Sierra SOL format
  
   DE sox             SoX native format
  
    E spdif           IEC958 - S/PDIF (IEC-61937)
  
    E svcd            MPEG-2 PS format (VOB)
  
   DE swf             Flash format
  
   D  thp             THP
  
   D  tiertexseq      Tiertex Limited SEQ format
  
   D  tmv             8088flex TMV
  
   DE truehd          raw TrueHD
  
   D  tta             True Audio
  
   D  txd             Renderware TeXture Dictionary
  
   DE u16be           PCM unsigned 16 bit big-endian format
  
   DE u16le           PCM unsigned 16 bit little-endian format
  
   DE u24be           PCM unsigned 24 bit big-endian format
  
   DE u24le           PCM unsigned 24 bit little-endian format
  
   DE u32be           PCM unsigned 32 bit big-endian format
  
   DE u32le           PCM unsigned 32 bit little-endian format
  
   DE u8              PCM unsigned 8 bit format
  
   D  vc1             raw VC-1
  
   D  vc1test         VC-1 test bitstream format
  
    E vcd             MPEG-1 System format (VCD)
  
   D  video4linux     Video4Linux device grab
  
   D  video4linux2    Video4Linux2 device grab
  
   D  vmd             Sierra VMD format
  
    E vob             MPEG-2 PS format (VOB)
  
   DE voc             Creative Voice file format
  
   D  vqf             Nippon Telegraph and Telephone Corporation (NTT) TwinVQ
  
   D  w64             Sony Wave64 format
  
   DE wav             WAV format
  
   D  wc3movie        Wing Commander III movie format
  
    E webm            WebM file format
  
   D  wsaud           Westwood Studios audio format
  
   D  wsvqa           Westwood Studios VQA format
  
   D  wv              WavPack
  
   D  x11grab         X11grab
  
   D  xa              Maxis XA File Format
  
   D  yop             Psygnosis YOP Format
  
   DE yuv4mpegpipe    YUV4MPEG pipe format

• Writing an MP4 file on the Mac with OpenCV ffmpeg

  13 janvier 2015, par Sameer Parekh

  I am using OpenCV with ffmpeg on a mac to write video. I’ve been able to successfully write .avi files using the codec/fourcc code, FMP4. I would like to write .mp4 files, however. When I try to write an .mp4 file using fourcc FMP4 I get this error :

  [mp4 @ 0x100b4ec00] Tag FMP4/0x34504d46 incompatible with output codec id '13' ( [0][0][0])

  When I use AVC1 I get the following error :

  [libx264 @ 0x104003000] broken ffmpeg default settings detected
  
  [libx264 @ 0x104003000] use an encoding preset (e.g. -vpre medium)
  
  [libx264 @ 0x104003000] preset usage: -vpre <speed> -vpre <profile>
  
  [libx264 @ 0x104003000] speed presets are listed in x264 --help
  
  [libx264 @ 0x104003000] profile is optional; x264 defaults to high
  
  Could not open codec 'libx264': Unspecified error
  
  </profile></speed>

  Does anyone here know the right codec to use with OpenCV and ffmpeg to write to an MP4 container on the Mac ?

  If AVC1 is the right codec, how do I install ffmpeg + OpenCV correctly ? I did

  brew install gpac
  
  brew install ffmpeg
  
  brew install opencv

  The call I am using to open the videowriter :

  fourcc = cv2.cv.CV_FOURCC('A', 'V', 'C', '1')   
  
  video_out = cv2.VideoWriter(
  
      filename=output_filename,
  
      fourcc=fourcc,
  
      fps=video_fps,
  
      frameSize=(video_width,video_height),
  
      isColor=1)

  When I run x264 --help I get

  % x264 --help
  
  x264 core:125
  
  Syntax: x264 [options] -o outfile infile
  
  
  
  Infile can be raw (in which case resolution is required),
  
    or YUV4MPEG (*.y4m),
  
    or Avisynth if compiled with support (no).
  
    or libav* formats if compiled with lavf support (no) or ffms support (no).
  
  Outfile type is selected by filename:
  
   .264 -> Raw bytestream
  
   .mkv -> Matroska
  
   .flv -> Flash Video
  
   .mp4 -> MP4 if compiled with GPAC support (no)
  
  Output bit depth: 8 (configured at compile time)
  
  
  
  Options:
  
  
  
    -h, --help                  List basic options
  
        --longhelp              List more options
  
        --fullhelp              List all options
  
  
  
  Example usage:
  
  
  
        Constant quality mode:
  
              x264 --crf 24 -o <output> <input />
  
  
  
        Two-pass with a bitrate of 1000kbps:
  
              x264 --pass 1 --bitrate 1000 -o <output> <input />
  
              x264 --pass 2 --bitrate 1000 -o <output> <input />
  
  
  
        Lossless:
  
              x264 --qp 0 -o <output> <input />
  
  
  
        Maximum PSNR at the cost of speed and visual quality:
  
              x264 --preset placebo --tune psnr -o <output> <input />
  
  
  
        Constant bitrate at 1000kbps with a 2 second-buffer:
  
              x264 --vbv-bufsize 2000 --bitrate 1000 -o <output> <input />
  
  
  
  Presets:
  
  
  
        --profile <string>      Force the limits of an H.264 profile
  
                                    Overrides all settings.
  
                                    - baseline,main,high,high10,high422,high444
  
        --preset <string>       Use a preset to select encoding settings [medium]
  
                                    Overridden by user settings.
  
                                    - ultrafast,superfast,veryfast,faster,fast
  
                                    - medium,slow,slower,veryslow,placebo
  
        --tune <string>         Tune the settings for a particular type of source
  
                                or situation
  
                                    Overridden by user settings.
  
                                    Multiple tunings are separated by commas.
  
                                    Only one psy tuning can be used at a time.
  
                                    - psy tunings: film,animation,grain,
  
                                                   stillimage,psnr,ssim
  
                                    - other tunings: fastdecode,zerolatency
  
  
  
  Frame-type options:
  
  
  
    -I, --keyint <integer or="or"> Maximum GOP size [250]
  
        --tff                   Enable interlaced mode (top field first)
  
        --bff                   Enable interlaced mode (bottom field first)
  
        --pulldown <string>     Use soft pulldown to change frame rate
  
                                    - none, 22, 32, 64, double, triple, euro (requires cfr input)
  
  
  
  Ratecontrol:
  
  
  
    -B, --bitrate <integer>     Set bitrate (kbit/s)
  
        --crf <float>           Quality-based VBR (0-51) [23.0]
  
        --vbv-maxrate <integer> Max local bitrate (kbit/s) [0]
  
        --vbv-bufsize <integer> Set size of the VBV buffer (kbit) [0]
  
    -p, --pass <integer>        Enable multipass ratecontrol
  
                                    - 1: First pass, creates stats file
  
                                    - 2: Last pass, does not overwrite stats file
  
  
  
  Input/Output:
  
  
  
    -o, --output <string>       Specify output file
  
        --sar width:height      Specify Sample Aspect Ratio
  
        --fps   Specify framerate
  
        --seek <integer>        First frame to encode
  
        --frames <integer>      Maximum number of frames to encode
  
        --level <string>        Specify level (as defined by Annex A)
  
        --quiet                 Quiet Mode
  
  
  
  Filtering:
  
  
  
        --vf, --video-filter <filter0>/<filter1>/... Apply video filtering to the input file
  
  
  
        Filter options may be specified in <filter>:<option>=<value> format.
  
  
  
        Available filters:
  
        crop:left,top,right,bottom
  
        select_every:step,offset1[,...]
  
  </value></option></filter></filter1></filter0></string></integer></integer></string></integer></integer></integer></float></integer></string></integer></string></string></string></output></output></output></output></output></output>

  Thanks,
   s