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QT is file extension of Apple QuickTime
media format. QT functions as a multimedia container file
that contains one or more tracks, each of which stores a
particular type of data: audio, video, effects, text, or
subtitles.
WMV file contains video and audio
streams respectively using Windows Media Video codec and
Windows Media Audio codec.
To convert QT to wmv file, please install the
QuickTime Player and
QuickTime Directshow filter.
Download
WMV Converter which can
convert qt to wmv file. Select a qt file, change some
parameters such as the video encoding bitrate, audio
encoding bitrate, resolution, frame rate etc if necessary.
If set the customized size to watch high
definition in 1280x720 (720p) or 1920x1080 (1080p)
resolutions, and increase bit rate, you may convert qt to
wmv HD.
H.261 is the first practical digital
video coding standard designed by ITU-T to develop
conference TV and video telephony on ISDN. It becomes the
design framework of later International Standard of Video
Coding including MPEG-1, MPEG-2/H.262 and H.263. H.261.
It only deals with CIF and QCIF image formats by dividing
every frame into images layer, Acer block group layer, Acer
block and block layer. H.261 output rate is constant, while
the image quality is unsteady.
H.263 is the standard draft of ITU-T
designed for low bit-stream communications. Actually the
standard could be used in broader bitstream scope but not
limit to low bit-stream. What痴 more, it痴 thought to be
used to replace H.261.The coding algorithm of H.263 is the
same with that of H.261.but there池e still some differences.
e.g. H.263 adopts semi-precision for motion compensation
while H.261 adopts all pixel accuracy and filtering cycle;
H.263 contains four consultable options to improve
performance.
After install H.261 or H.263 decoder,
wmv converter can convert h.261/h.263 to wmv file. |
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