Overview AVCHD
file organization on panasonic , canon solid-state avchd camcorders
for video compression, avchd uses mpeg-4 avc/h.264 standard, supporting variety of standard, high definition, , stereoscopic (3d) video resolutions. audio compression, supports both dolby ac-3 (dolby digital) , uncompressed linear pcm audio. stereo , multichannel surround (5.1) both supported.
aside recorded audio , video, avchd includes many user-friendly features improve media presentation: menu navigation, simple slide shows , subtitles. menu navigation system similar dvd-video, allowing access individual videos common intro screen. slide shows prepared sequence of avc still frames, , can accompanied background audio track. subtitles used in camcorders timestamp recordings.
audio, video, subtitle, , ancillary streams multiplexed mpeg transport stream , stored on media binary files. usually, memory cards , hdds use fat file system, while optical discs employ udf or iso9660.
at file system level, structure of avchd derived blu-ray disc specification, not identical it. in particular, uses legacy 8.3 file naming convention, while blu-ray discs utilize long filenames (this may caused fact fat implementations utilizing long file names patented microsoft , licensed on per unit sold basis). difference location of bdmv directory, contains media files. on dvd-based camcorder bdmv directory placed @ root level, on blu-ray disc. on hdd-based canon hg10 camcorder bdmv directory located in avchd directory, placed @ root level. solid-state panasonic , canon camcorders nest avchd directory inside private directory. following standard agreed upon many still camera manufacturers, solid-state camcorders have root-level dcim directory still images.
avchd compatible blu-ray disc format , can authored without re-encoding on blu-ray discs or dvds, though not blu-ray disc players compatible avchd video authored on dvd media, format known avchd disc.
avchd recordings can transferred computer connecting camcorder via usb connection. removable media sdhc , memory stick cards or dvds can read on computer directly. copying files avchd camcorder or removable media can performed faster tape-based camcorder, because transfer speed not limited realtime playback.
just editing dvcpro hd , hdv video once demanded expensive high-end computer, avchd editing software requires powerful machines. compared hdv, avchd requires 2-4x processing power realtime playback, placing greater burden on computer s cpu , graphics card. improvements in multi-core computing , graphics processor acceleration bring avchd playback mainstream desktops , laptops.
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