Index: en/encoding-guide.xml
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RCS file: /cvsroot/mplayer/main/DOCS/xml/en/encoding-guide.xml,v
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+
+Choosing the video codec
+
+
+ Choosing the video codec to use depends on several factors, some of
+ which widely depend on personal taste and technical constraints.
+
+
+
+ Compression efficiency:
+ It's quite easy to understand that newer generation of codecs are made
+ to yield better picture quality than previous generations.
+ Therefore, you cannot be wrong
+
+ Be careful though: decoding DVD-resolution MPEG-4 AVC videos
+ requires a fast machine (i.e. a Pentium 4 over 1.5Ghz or a Pentium M
+ over 1Ghz).
+
+ choosing MPEG-4 AVC codecs like
+ x264 instead of MPEG-4 ASP codecs
+ such as libavcodec MPEG-4 or
+ XviD.
+ (To get a better grasp of what are the fundamental differences between
+ MPEG-4 ASP and MPEG-4 AVC are, you should definitely read the entry
+ "15 reasons why MPEG4 sucks"
+ from Michael Niedermayer's blog.)
+ Likewise, you should get better quality using MPEG-4 ASP instead
+ of MPEG-2 codecs.
+
+
+ However, newer codecs which are in heavy development can suffer from
+ some bugs which have not been spotted at the time you used that codec,
+ ruining your encode.
+ That's unfortunately sometimes the price to pay for bleeding edge
+ technologies.
+
+
+ What's more, newer codecs means in general that you'd need some training
+ time to get used to their set of options so that you know what to tune
+ depending on what kind of picture quality you're after.
+
+
+
+ Hardware compatibility:
+ Standalone video players are usually quite behind what is going on
+ in video codecs world.
+ That means that most only support MPEG-2 and MPEG-4 ASP
+ (beware: usually, not all MPEG-4 ASP features are supported).
+ Please refer to the technical specs of your player for more informations.
+
+
+
+ Best quality per fps:
+ Codecs that have been around for some time (such as
+ libavcodec MPEG-4 and
+ XviD) are usually heavily
+ optimized using all kinds of smart algorithms and SIMD assembly code.
+ That's why they tend to yield the best quality per fps.
+ However, they may have some very advanced options that, if enabled,
+ will make the encode really slow for marginal gains.
+
+
+ If you are after blazing speed you should stick around the default
+ settings of the video codec (which doesn't mean you should not experiment
+ with some of the options which are mentioned in other sections
+ of this guide).
+
+
+ You may also consider choosing a codec that can do multi-threaded
+ processing.
+ libavcodec MPEG-4 does
+ allow that, at the price of lowering picture quality for small speed
+ gains.
+ XviD has some experimental
+ patches available to boost encoding speed by about 40-60% in typical
+ cases with low picture degradation.
+ x264 also allows multi-threaded
+ encoding, which currently speeds-up encoding by 15-30% while lowering
+ PSNR by about 0.05dB.
+
+
+
+ Personal taste:
+ This is were it gets almost irrational: For the same reason that some
+ hanged on to DivX3 for years when newer codecs were already doing wonders,
+ some folks will prefer XviD
+ over libavcodec MPEG-4 or
+ x264.
+
+
+ Make your own judgment, and don't always listen to what some people will
+ tell you to do or think: The best codec is the one you master the best,
+ and the one that looks best to your eyes on your display
+
+ The same encode may not look the same on someone else's monitor or
+ when played back by a different decoder so future-proof your encodes by
+ playing them back on different setups.!
+
+
+
+ Please refer to the section
+ selecting codecs and container formats
+ to get a list of supported codecs.
+
+
+
Audio