From 5461fc33baed9455a39b7ae1a4793a330251758c Mon Sep 17 00:00:00 2001 From: gabucino Date: Sat, 10 Aug 2002 20:26:43 +0000 Subject: continuing paragraph reformatting git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@6961 b3059339-0415-0410-9bf9-f77b7e298cf2 --- DOCS/formats.html | 166 ++++++++++++++++++++++++++++-------------------------- 1 file changed, 85 insertions(+), 81 deletions(-) (limited to 'DOCS/formats.html') diff --git a/DOCS/formats.html b/DOCS/formats.html index dc7cc96d67..d771c2655f 100644 --- a/DOCS/formats.html +++ b/DOCS/formats.html @@ -13,21 +13,22 @@

2.1 Supported formats

It is important to clarify a common mistake. When people see a file with a -.AVI extension, they immediately conclude that it is not an MPEG file. -That is not true. At least not entirely. Contrary to popular belief such a file -can contain MPEG1 video.

+ .AVI extension, they immediately conclude that it is not an MPEG file. + That is not true. At least not entirely. Contrary to popular belief such a + file can contain MPEG1 video.

You see, a codec is not the same as a file format.
-Examples of video codecs are: MPEG1, MPEG2, DivX, Indeo5, 3ivx.
-Examples of file formats are: MPG, AVI, ASF.
+ Examples of video codecs are: MPEG1, MPEG2, DivX, Indeo5, 3ivx.
+ Examples of file formats are: MPG, AVI, ASF.

-

In theory, you can put an OpenDivX video and MP3 audio -into an MPG format file. However, most players will not play it, since -they expect MPEG1 video and MP2 audio (unlike AVI, MPG does not have the -necessary fields to describe its video and audio streams). -Or you might put MPEG1 video into an AVI file. FFmpeg -and MEncoder can create these files.

+

In theory, you can put an OpenDivX video and MP3 audio into an MPG + format file. However, most players will not play it, since they expect MPEG1 + video and MP2 audio (unlike AVI, MPG does not have the + necessary fields to describe its video and audio streams). Or you might put + MPEG1 video into an AVI file. + FFmpeg and + MEncoder can create these files.

@@ -39,38 +40,39 @@ and MEncoder can create these files.

MPEG files come in different guises:

Series of frames form independent groups in MPEG files. This means that you -can cut/join an MPEG file with standard file tools (like dd, -cut), and it remains completely functional.

+ can cut/join an MPEG file with standard file tools (like dd, + cut), and it remains completely functional.

-

One important feature of MPGs is that they have a field to describe -the aspect ratio of the video stream within. For example SVCDs have -480x480 resolution video, and in the header that field is set to 4:3, so that -it is played at 640x480. AVI files do not have this field, so they have to be -rescaled during encoding or played with the -aspect option.

+

One important feature of MPGs is that they have a field to describe the + aspect ratio of the video stream within. For example SVCDs have 480x480 + resolution video, and in the header that field is set to 4:3, so that it is + played at 640x480. AVI files do not have this field, so they have to be + rescaled during encoding or played with the -aspect option.

2.1.1.2 AVI files

-

Designed by Microsoft, AVI (Audio Video Interleaved) is a -widespread multipurpose format currently used mostly for DivX and DivX4 -video. It has many known drawbacks and shortcomings (for example in streaming). -It supports one video stream and 0 to 99 audio streams. File size is limited to -2GB, but there exists an extension allowing bigger files called OpenDMS. -Microsoft currently strongly discourages its use and encourages ASF/WMV. Not that -anybody cares.
+

Designed by Microsoft, AVI (Audio Video Interleaved) is a widespread + multipurpose format currently used mostly for DivX and DivX4 video. It has + many known drawbacks and shortcomings (for example in streaming). It + supports one video stream and 0 to 99 audio streams. File size is limited to + 2GB, but there exists an extension allowing bigger files called + OpenDMS. Microsoft currently strongly discourages its use and + encourages ASF/WMV. Not that anybody cares.

There is a hack that allows AVI files to contain an Ogg Vorbis audio stream, but makes them incompatible with standard AVI. MPlayer @@ -80,9 +82,9 @@ anybody cares.
problem.

Note: DV cameras create raw DV streams that DV grabbing utilities -convert to two different types of AVI files. The AVI will then contain either -separate audio and video streams that MPlayer can play or the raw DV -stream for which support is under development.

+ convert to two different types of AVI files. The AVI will then contain either + separate audio and video streams that MPlayer can play or the raw DV + stream for which support is under development.

There are two kinds of AVI files:

Any audio and video codec is allowed, but note that VBR audio is not well -supported by most players. The file format makes it possible to use VBR -audio, but most players expect CBR audio, thus they fail with VBR. VBR is -uncommon and the Microsoft AVI specs only describe CBR audio. Most AVI -encoders/multiplexers create bad files when using VBR audio. There are only -two known exceptions: NanDub and MEncoder.

+ supported by most players. The file format makes it possible to use VBR + audio, but most players expect CBR audio, thus they fail with VBR. VBR is + uncommon and the Microsoft AVI specs only describe CBR audio. Most AVI + encoders/multiplexers create bad files when using VBR audio. There are only + two known exceptions: NanDub and MEncoder.

2.1.1.3 ASF/WMV files

ASF (active streaming format) comes from Microsoft. They developed two -variants of ASF, v1.0 and v2.0. v1.0 is used by their media tools (Windows -Media Player and Windows Media Encoder) and is very secret. v2.0 is published -and patented :). Of course they differ, there is no compatibility at all (it is -just another legal game). MPlayer supports only v1.0, as nobody has ever seen -v2.0 files :). Note that ASF files nowadays come with the extension .WMA or -.WMV.

+ variants of ASF, v1.0 and v2.0. v1.0 is used by their media tools (Windows + Media Player and Windows Media Encoder) and is very secret. v2.0 is published + and patented :). Of course they differ, there is no compatibility at all (it + is just another legal game). MPlayer supports only v1.0, as nobody has + ever seen v2.0 files :). Note that ASF files nowadays come with the extension + .WMA or .WMV.

2.1.1.4 QuickTime/MOV files

-

These formats were designed by Apple and can contain any codec, CBR or VBR. -They usually have a .QT or .MOV extension. Ever since the MPEG4 group chose -QuickTime as the recommended file format for MPEG4, their MOV files come with a -.MPG or .MP4 extension (Interestingly the video and audio streams in these -files are real MPG and AAC files. You can even extract them with the --dumpvideo and -dumpaudio options.).

+

These formats were designed by Apple and can contain any codec, CBR or VBR. + They usually have a .QT or .MOV extension. Ever since the MPEG4 group chose + QuickTime as the recommended file format for MPEG4, their MOV files come with + an + .MPG or .MP4 extension (Interestingly the video and audio streams in these + files are real MPG and AAC files. You can even extract them with the + -dumpvideo and -dumpaudio options.).

Note: Most new QuickTime files use Sorenson video and QDesign Music audio. See our Sorenson codec @@ -144,26 +147,26 @@ files are real MPG and AAC files. You can even extract them with the

2.1.1.5 VIVO files

-

MPlayer happily demuxes VIVO file formats. The biggest disadvantage of -the format is that it has no index block, nor a fixed packet size or sync bytes -and most files lack even keyframes, so forget seeking!

+

MPlayer happily demuxes VIVO file formats. The biggest disadvantage + of the format is that it has no index block, nor a fixed packet size or sync + bytes and most files lack even keyframes, so forget seeking!

The video codec of VIVO/1.0 files is standard h.263. The video codec -of VIVO/2.0 files is a modified, nonstandard h.263v2. The audio is the same, -it may be g.723 (standard), or Vivo Siren.

+ of VIVO/2.0 files is a modified, nonstandard h.263v2. The audio is the + same, it may be g.723 (standard), or Vivo Siren.

-

See the VIVO video codec -and VIVO audio codec sections for installation -instructions.

+

See the VIVO video codec and + VIVO audio codec sections for installation + instructions.

2.1.1.6 FLI files

-

FLI is a very old file format used by Autodesk Animator, but it is -a common file format for short animations on the net. MPlayer demuxes -and decodes FLI movies and is even able to seek within them (useful when -looping with the -loop option). FLI files do not have keyframes, so the picture -will be messy for a short time after seeking.

+

FLI is a very old file format used by Autodesk Animator, but it is a + common file format for short animations on the net. MPlayer demuxes + and decodes FLI movies and is even able to seek within them (useful when + looping with the -loop option). FLI files do not have keyframes, + so the picture will be messy for a short time after seeking.

2.1.1.7 RealMedia (RM) files

@@ -178,19 +181,20 @@ will be messy for a short time after seeking.

2.1.1.8 NuppelVideo files

NuppelVideo -is a TV grabber tool (AFAIK:). MPlayer can read its .NUV -files (only NuppelVideo 5.0). Those files can contain uncompressed YV12, -YV12+RTJpeg compressed, YV12 RTJpeg+lzo compressed, and YV12+lzo compressed -frames. MPlayer decodes them all (and also encodes them with -MEncoder to DivX/etc!). Seeking works.

+ is a TV grabber tool (AFAIK:). MPlayer can read its .NUV files (only + NuppelVideo 5.0). Those files can contain uncompressed YV12, YV12+RTJpeg + compressed, YV12 RTJpeg+lzo compressed, and YV12+lzo compressed frames. + MPlayer decodes them all (and also encodes them with + MEncoder to DivX/etc!). Seeking works.

2.1.1.9 yuv4mpeg files

-

yuv4mpeg / yuv4mpeg2 is -a file format used by the mjpegtools programs. -You can grab, produce, filter or encode video in this format using these tools. -The file format is really a sequence of uncompressed YUV 4:2:0 images. +

yuv4mpeg / yuv4mpeg2 is a file + format used by the mjpegtools programs. + You can grab, produce, filter or encode video in this format using these + tools. The file format is really a sequence of uncompressed YUV 4:2:0 + images.

@@ -224,10 +228,10 @@ The file format is really a sequence of uncompressed YUV 4:2:0 images.

2.1.2.1 MP3 files

You may have problems playing certain MP3 files that MPlayer will -misdetect as MPEGs and play incorrectly or not at all. This cannot be fixed -without dropping support for certain broken MPEG files and thus will remain -like this for the foreseeable future. The -demuxer flag described -in the manpage may help you in these cases.

+ misdetect as MPEGs and play incorrectly or not at all. This cannot be fixed + without dropping support for certain broken MPEG files and thus will remain + like this for the foreseeable future. The -demuxer flag + described in the manpage may help you in these cases.

2.1.2.2 WAV files

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