B (Bi-directional) frames
B frames are encoded using both previous and next frames as reference and are better compressed than P frames and I frames.
codec
A codec is technology (software or hardware) that compress and decompress data. By using codecs for compressing audio and video data into smaller packets that do not consume as much hard disk space or network bandwidth, multimedia applications can provide richer and fuller content.
I (Intraframe) frames
I frames are encoded without reference to another frame, providing support for random access. See also P frames and B frames.
interframe
Interframe compressors compress the differences between adjacent frames. Generally, the interframe algorithms provide higher compression ratios than intraframe algorithms. The trade-off to the higher compression ratios of interframe compressions is speed. Inter-frame compressors usually can not compress video in real time, while intraframe compression can do real time compression. LEAD offers the following interframe compressors: H.264, H.263 and MPEG/MPEG-2
intraframe
Each transmitted video image or sample is compressed independently. LEAD offers the following intraframe compressors: MCMP/MJPEG, MJPEG2000 and MCMW
lossless compression
Compression techniques can be categorized into two groups, lossless and lossy. When data has been compressed using a lossless compression technique, the result of the decompression will be bit for bit exactly the same as the original data before compression. Generally, lossless compression can not achieve anywhere near the compression ratios of that of lossy compression. The following LEAD codecs offer lossless data compression: MJPEG2000 and MCMW.
lossy compression
Compression techniques can be categorized into two groups, lossless and lossy. When data is compressed using a lossy compression technique, the result of the decompression will not exactly match the original. Most lossy compression techniques allow you to control how much loss (quality or q-factor). The following LEAD codecs offer lossy compression: H.264, H.263, MPEG/MPEG-2, MCMP/MJPEG, MJPEG2000 and MCMW
P (Predictive) frames
P frames are encoded using the previous frame as reference. P frames are more highly compressed than I frames.
SAD HADAMAR
SAD HADAMARD is a calculation of the sum of absolute difference indirectly by applying HADAMARD transform to the block before calculating SAD increasing the compression ratio. The following LEAD codecs make use of SAD HADAMAR: H264
temporal compression
Temporal compression is the process of only encoding the difference between successive frames, instead of the frames themselves. Any given frame is constructed from the prediction from a previous frame and may be used to predict the next frame. The following LEAD codecs make use of temporal compression: H264
wavelet
Wavelet transforms are mathematical formulas that represent complex structures in an image, thereby compressing an extremely large amount of image data into a relatively small amount of compressed data. This compression technique allows applications to save compressed imagesor videos with higher compression ratios and better quality as compared to any other intraframe compression technique. The following LEAD codecs make use of wavelet compression: H.264, H.263, MJPEG2000 and MCMW
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