 2008/05/09
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Last update 2002/02/28
The Labs - Design & Functionality For The NetOpen-Source Video Resources for UNIX
- Introduction
- Resources
- AVI
- MPEG & MJPEG
- Web Video (Streaming)
- DVD
- Other Platforms
More and more video approaches for UNIX (Linux, FreeBSD)
become available, and also more codecs become available.
In the long run something like AdobePremiere-like GNU based Video-editing system which
uses GIMP-plugins to render fadings or effects (see film.gimp.org).
It has to be admitted that SGI provides since years
for high-end top-level video-capture and video-editing
systems, unfortunatly few can afford to buy.
Note: The movie "Titanic" was rendered on Alpha-based machines running Linux, but
models were created on NT and SGI-machines.
Codecs | |
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Streamers / Encoders | | | GStreamerOpen-source streaming media framework (mp3, MPEG-1 and -2, AC3, Ogg Vorbis, JPEG, RTJPEG, WAV, AU, V4L etc) |
FFMpeg - Multi codec streamingMPEG, ASF, AVI, WAV, SWF, Realmedia/Realaudio, PGM, PPM, JPEG, AC3, Raw MJPEG, MPEG video |
Fame: MPEG EncoderProvides MPEG "software-only" encoder with MMX, and network capability (no sound) |
| The MJPEG/Linux SquareMPEG 1/2, MJPEG and editting / basic DVCR functionality |
MJPEG: Marvel & Rainbow RunnerWorking |
QuickTime for LinuxLibrary to read/write QT movies |
| IomageBuz & Linuxiomage-buz no longer produced |
|
Misc. Applications | |
|
Viewers | | | XineVideo player: mpeg, avi, and other formats |
XMMSActually a mp3 player but with a plugin also displaying MPEG and AVI videos (FreeBSD-users: check /usr/ports/graphics/xmms-*) |
XANIMGood video-view for X11, supports many formats |
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Right now (March 2002) there
are only semi-professional video-recording or
video-editing software available for UNIX
(Linux, FreeBSD). Especially Brooktree (Bt848/878) based cards are unstable
and unreliable (independent of OS and mainboards).
Motion JPEG (Zoran) based video-capture cards seem more stable.
Theory | |
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How To Video Record | |
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AVI support under UNIX is quite rare, but here some references:
| Linux AVI FileLibraryAVI Library for Linux, supported formats: IndeoV3.2,4.1, MPEG-4v1,2, DivX, Cinepak Video, ATI VCR-2, I263, MJPEG, MS-ADPCM, PCM, AC3, IMA ADPCM, MPEG Layer-1,2,3, MSN Audio, GSM 6.1 Audio |
JPEG to AVIWorks with XANIM, but not on WIN95 |
PPM to AVINo sound support, but works on WIN95 |
| AVI FAQVery good resource, keep checking it |
FourCC (AVI)Overview of all the codecs |
OpenDML AVI FormatPDF: MJPEG extension defined for AVI |
FreeBSD | | Install /usr/ports/graphics/avifile which makes also aviplay which plays
the famous DiVX;-) files too.
|
MPEG (Moving Picture Experts Group) and MJPEG (Motion JPEG) are not the same, even the sound alike.
MPEG is a standard of
how to store frames, with predictive frames and vectors from which later
frames can be calculated, and the whole things gets quite complicate, you find
the detailed infos at MPEG.Org. In general
there are following standards:
| MPEG-1 | 1.5Mbit/s |
| MPEG-2 | 1.5Mbit/s - 200Mbit/s |
| MPEG-4 | 10Kbit/s - 100Kbit/s |
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It has to be noted, that the actual frame data compression can be in different format, MPEG just
defines the way the data is stored. Often also the YUV data compression is
displayed by three numbers
- 4:4:4 (4Y,4U,4V) for each pixels Y,U,V is stored
- 4:2:2 (4Y,2U,2V) for each pixels Y, but U V only for each second pixel
- 4:2:0 (4Y,U,V) for each pixel Y, but U or V (alternate) for each second pixel
- 4:1:1 (4Y,U,V) for each pixel Y, for each 4th pixel U & V
MJPEG compresses each frame using JPEG compression with a certain quality,
the advantage is that MJPEG allows frame exact cutting, whereas MPEG cutting require
overhead to cut frame exact.
MPEG & MJPEG Resources for UNIX:
| FXTV (FreeBSD X TV)Bt848 with MPEG streaming (IYUV & PPM) |
Linux Motion VideoExperimental MJPEG package |
MPEG.OrgThe best resource center with players |
| FFMpeg - Multi codec streamingMPEG, ASF, AVI, WAV, SWF, Realmedia/Realaudio, PGM, PPM, JPEG, AC3, Raw MJPEG, MPEG video |
One thing has to be noted, if you record MJPEG you lose data as it's not true RGB 24Bit colors,
but JPEG compression used for every frame.
Mark Podlipec (XAnim) different MJPEG implementations:
Quicktime's MJPEG-A(MJPA) and MJPEG-B(MJPB) formats are different than
AVI's "MJPG" format. Although MJPA and MJPG are similiar. Possibly
different field orders in some instances. Quicktime and AVI's JPEG
codec are interchangable(essentially just JFIF).
| Video Lab5. Web Video (Streaming)
|
Some people believe MJPEG for the web, it has some advantages,
but unless there is more software & tools I doubt its success for the web-use.
Always keep an eye on Progressive Networks (Real.Com)
has done and still does a good job with highly compressed audio & video for
8kb/s upto 1Mb/s rate.
The final video you may like to share on the web, then several approaches
are possible (ordered by our own experience):
- RealVideo: Real.Com: best compression from
8kb/s upto 1Mb/s, one file several transfer rates supported (5.0 or later).
Video conversion-tool support on UNIX (Linux, IRIX) available by February 1999 finally.
- Shockwave: Flash: Flash Plugin (Linux), authoring tools only for
Win/MAC (not Linux yet).
- MPEG: MPEG.Org: good codec, but not very known,
good support of creation tools for UNIX-based systems, also MPEG players available.
- Animated GIF: GIFMerge: animated GIFs, rather cheap approach,
but for blinking light it's sufficient, good for complex script-based animations.
- Animated GIF: GIMP: supports animated GIFs using layers,
best approach for complex but hand-made animations.
- Java Applet: Java: using a java-applet to animate pictures
or show a video, in short: instable, immense memory overhead, slow.
As soon there are hardware & software we at The Labs will provide a
video toolbox called Raw Video Studio, like Raw Sound Studio has
been for audio.
| FFMpeg - Multi codec streamingMPEG, ASF, AVI, WAV, SWF, Realmedia/Realaudio, PGM, PPM, JPEG, AC3, Raw MJPEG, MPEG video |
Xiphophorusmultimedia open-source effort |
StreamingServer.OrgOpen-source streaming server |
| Linux QuickTime PlayerVery promising |
DVD are encrypted and so far no sources are available to crack them.
It has to be mentioned that on Win95/98 are tools available to
read out DVD's and write them back as MPEG-4.
| Video Lab7. Other Platforms
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Last update 2002/02/28 
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