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AVC-Intra is a type of video coding developed by Panasonic, and then supported in products made by other companies. AVC-Intra is available in Panasonic's high definition broadcast products, such as, for example, their P2 card equipped broadcast cameras.〔(【引用サイトリンク】title=AJ-HPX2000 brochure )〕〔 ==Technical details== Panasonic announced AVC-Intra codec support in April 2007. The use of AVC-Intra provides production quality HD video at bit rates more normally associated with electronic news gathering applications, permitting full resolution, 10-bit field capture of high quality HD imagery in one piece camera-recorders. AVC-Intra is compliant with the H.264/MPEG-4 AVC standard and Panasonic claims to follow the SMPTE RP 2027–2007 recommended practice specification.〔(【引用サイトリンク】title=AVC-Intra (H.264 Intra) Compression, Technical Overview )〕 Analysis by the x264 project has shown that Panasonic does not comply with this specification〔(【引用サイトリンク】title=Git commit )〕 AVC-Intra was intended for video professionals who have to store HD digital video for editing and archiving. It defines 10-bit intra-frame only compression, which is easy for editing and preserves maximum video quality. The technology significantly outperforms the older HDV (MPEG2 based) and DVCPRO HD (DV based) formats, allowing the codec in certain conditions to maintain better quality in half the storage space of DVCPRO HD. AVC-Intra defines two classes: * AVC-Intra 50: * * nominally 50 Mbit/s, size of each frame is fixed * * CABAC entropy coding only. * * 1920 × 1080 formats are High 10 Intra Profile, Level 4 * * 1280 × 720 formats are High 10 Intra Profile, Level 3.2 * * 4:2:0 chrominance sampling * * frames are horizontally scaled by 3/4 (1920x1080 is scaled to 1440x1080. 1280 × 720 is scaled to 960x720) * AVC-Intra 100: * * nominally 100 Mbit/s, size of each frame is fixed * * CAVLC entropy coding only. * * All formats are High 4:2:2 Intra Profile, Level 4.1 * * 4:2:2 chrominance sampling * * frames are not scaled Common to both classes; * Frame rates: 1920 × 1080 (23.98p / 25p / 29.97p / 50i / 59.94i), 1280 × 720 (23.98p / 25p / 29.97p / 50p / 59.94p) * 10 bit luma and chroma Panasonic's implementation of AVC-Intra codec has following limitations: 8 × 8 transform only, 8 × 8 intra prediction only, 10 slices per picture, MBAFF for interlace material, custom quantization matrices for each class and each resolution.〔(【引用サイトリンク】title=AVC-Intra Technical Overview by Panasonic Broadcast )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「AVC-Intra」の詳細全文を読む スポンサード リンク
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