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Microsoft, AVI - WMV9 conversion becomes a very popular way nowadays.
WMV-HD is a kind of video compression format founded by Microsoft. It is a new member of
WMV series with its compression rate even higher than MPEG-2 standard. For the same 2-hour
High Definition video programs, they can be compressed to 30GB if with MPEG-2; while with
WMV-HD such kind of high compression coding algorithm, they can be compressed to about
15GB without any video quality losing. Although WMV-HD is an unique standard of Microsoft,
thanks to the wide propaganda by Microsoft, WMV format now has been a most frequently used
video format by HD videos. Moreover, WMV-HD format is perfectly supported by Windows
Media Player, which brings much convenience to our users.
VC-1 is the informal name of SMPTE standard 421M Codec draft (superset of WMV-9 and
WMV-HD). VC-1 originates from WMV9 technique of Microsoft. Microsoft submitted VC-1
technique to SMPTE (Society of Motion Picture and Television Engineers) for deliberation and
formally issued as a standard named as SMPTE-421M on April 3
rd
, 2006. From then on VC-1
coding technique is no longer exclusively owned by Microsoft, instead, it becomes a video format
that anyone can develop, support and use.
MPEG-2 TS
Different with DVD-adopted MPEG-2 format, HD video uses the MPEG-2 TS format. It is a
kind of video stream format, mainly used for the real-time programs transmission. HD video with
MPEG-2 TS format is very common on the broadcast network. It generally uses suffixes
of .mpg, .tp, .ts.. HD video files using MPEG-2 TS format for compression are usually very
large. Take a 90-minute movie for instance, its file size is usually above 8GB, some even larger
than 15GB. It also has difficulty in playing the HD video files with suffixes of .tp and .ts. The
reason is that the files contain AC’3 audio information and MPEG-2 video information so they
need a professional software to play.
MPEG-1
MPEG-1 standard was issued on August, 1993, which is a generic term of a group of audio &
video coding system authorized by MPEG (Moving Picture Experts Group). It was used for
transferring codes of motive pictures and its accompanying sound in digital media, with a digital
transmission rate of 1.5 Mbps. Later the date rate was raised to 4 Mbps in order to obtain higher
video quality. MPEG-1 now is mainly applied to digital medium like CD-ROM, Video-CD,
CD-1 etc.
MPEG-2
In 1994 MPEG organization issued MPEG-2 compression standard to realize the probability of
mutual operation application and video/audio services. MPEG-2 standard aims at SDTV and
HDTV compression proposal and detailed stipulation of system level in their various applications.
The bit rate varies from 3 Mbps to 100 Mbps. The standard norms are in ISO/IEC13818.
MPEG-2 is not a simple upgrade of MPEG-1, instead MPEG-2 developed more detailed standards
and further complete in its aspects of system and transmission. MPEG-2 especially adapts to
digital TV coding broadcasting and transmission, is recognized as the coding standard of SDTV