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  • Audio and Video codec summary

    2009-08-14 14:23:19

    (All the content is digested from wikipedia)


    AAC: Advanced Audio Codec

    Ø  AAC is developed with the cooperation and contribution of companies including Fraunhofer IIS, AT&T Bell Lab, Dolby, Sony and Nokia, and is officially declared by Motion Picture Expert Group in 1997.

    Ø  AAC is specified both as Part 7 of MPEG-2 standard and Part 3 of MPEG-4 standard. It is designed to be the successor of MP3.

    Ø  Support: 8kHz – 96kHz, 48 Channels.

    Ø  No licenses or payments are required to be able to stream or distribute content in AAC format; however, a patent license is required for all manufacturers or developers of AAC codecs.

    Ø  Supported Portable Players: Apple iPod, Microsoft Zune, SanDisk Sansa, Sony PlayStation Portable, Nintendo DSi…

    Ø  Supported Mobile Phones: Nokia, Motorola, Samsung, Sony Ericsson, BenQ-Siemens, Philips.

    Ø  Almost all the current computer media players include AAC decoder.


    AC-3/Dolby Digital

    Ø  Dolby Digital (AC-3) is the marketing name for a series of lossy audio compression technologies developed by Dolby Lab.

    Ø  Dolby Digital includes similar technologies, which include Dolby Digital, Dolby Digital EX, Dolby Digital Live, Dolby Digital Surround EX, Dolby Digital Plus, Dolby Digital TrueHD.

    Ø  Dolby Digital codec has some aliases: DD, Dolby Surround AC-3 Digital, Dolby Stereo Digital, Dolby SR-Digital, SR-D, Audio Coding 3, AC-3, Audio Codec 3, Advanced Codec 3, ATSC A/52.


    ADPCM

    Ø  It is a variant of DPCM (differential pulse-code modulation) that varies the size of the quantization step, to allow further reduction of the required brandwidth for a given signal-to-noise ratio.

    It is developed in the early 1970s at Bell Labs.


    AMR: Adaptive multi-rate compression

    Ø  It is a patented audio data compression scheme optimized for speech coding.

    Ø  It is adopted as the standard speech codec by 3GPP.

    Ø  Support: 12.2, 10.2, 7.95, 7.40, 6.70, 5.90, 5.15 and 4.75 kbps.


    AMR-WB: Adaptive Multi Rate-WideBand:

    Ø  It is a patented speech coding standard developed after the AMR suing similar technology.


    AMR-WB+: Extended Adaptive Multi Rate-WideBand

    Ø  It is an audio codec that extends AMR-WB.

    Ø  It adds support for stereo signals and higher sampling rates.


     

    Cinepak

    Ø  It is a video codec designed to encode 320x240 resolution at 1x CD-ROM transfer rates.

    Ø  It was the primary video codec of early version of QuickTime and Microsoft Video for Windows, but later superseded by Sorenson Video, Intel Video and most MPEG-4.


    DivX

    Ø  DivX codec uses lossy MPEG-4 compression.

    Ø  Version:3.xx->4.0->5.0->6.0->7.0...


    DTS

    Ø  DTS: Digital Theater System is a multichannel digital surround sound format.

    Ø  Variants: DTS 70 mm, DTS-ES, DTS Neo:6, DTS 96/24, DTS-HD, DTS Connect…


    ffdshow

    Ø  ffdshow is a media decoder and encoder supporting MPEG-4, AVC and numerous other video and audio formats as well.

    Ø  It is free software released under the GPL license, running on Windows.


    FFV1

    Ø  It stands for “FF video codec 1”.

    Ø  It is a lossless intra-frame. video format.


    Grayscale

    Ø  Grayscale (or grayscale) digital image is an image in which the value of each pixel is a single sample.

    Ø  Grayscale images are with only two colors, black and white.


     

    H.263

    Ø  It is developed by ITU-T Video Coding Experts Group (VCEG) based on experience from H.261.

    It is designed as a low-bitrate compressed format for videoconferencing.


    H.264/MPEG-4 AVC

    Ø  H.264/MPEG-4 AVC is a standard for video compression which is developed by the ITU-T Video Coding Experts Group (VCEG) together with MPEG.

    Ø  H.264 standard is a “family of standards” which includes below profiles:

    Constrained Baseline Profile (CBP)

    Baseline Profile (BP)

    Main Profile (MP)

    Extended Profile (XP)

    High Profile (HiP)

    High 10 Profile (Hi10P)

    High 4:2:2 Profile (Hi422P)

    High 4:4:4 Predictive Profile (Hi444PP)

    High 10 Intra Profile

    High 4:2:2 Intra Profile

    High 4:4:4 Intra Profile

    CAVLC 4:4:4 Intra Profile

    Scalable Baseline Profile

    Scalable High Profile

    Scalable High Intra Profile 


    HE-AAC: High-Efficiency Advanced Audio Coding.

    Ø  It is a lossy data compression scheme for digital audio.

    Ø  It is an extension of Low Complexity AAC (AAC-LC).

    Ø  HE-AAC v1, HE-AAC v2.


    Huffman

    Ø  Huffman coding is an entropy encoding algorithm used for lossless data compression.


    Indeo

    Ø  Indeo Video is a video codec developed by Intel then sold to Ligos Corporation in 2000.

    Ø  Versions: Indeo 2 and 3 have decoders in FFmpeg

                Indeo 4 and 5 are not supported by any open source decoders

                Indeo 5 decoders exist for Windows, Mac…

                Indeo 5.11 is a used on all versions of Windows except Vista and Win7

                Indeo 5.2 is created for Vista.


    LPCM: Liner pulse code modulation

    Ø  It is a particular method of pulse code modulation.

    Ø  PCM and LPCM are referred to the format used in WAV files.

    Ø  LPCM data also may be commonly stored in other formats such as AIFF.


    Motion JPEG

    Ø  It is an informal name for a class of video formats where each video frame. or interlaced field of a digital video sequence is separately compressed as a JPEG image.

    Ø  It is now used by many portable devices with video-capture capability.


    MPEG-1 Audio

    Ø  Lossy data compression.

    Ø  It is based on the existing MUSICAM and ASPEC audio formats.

    Ø  It including the three audio “layers” now known as MP1, MP2, MP3, is finalized by December 1991.

     

    MPEG-1 Audio Layer I: mp1

    Ø  Support: 32kHz, 44.1kHz, 48kHz, 32kbps, 64kbps, 96kbps, 128kbps, 160kbps, 192kbps, 224kbps, 256kbps, 288kbps, 320kbps, 352kbps, 384kbps, 416kbps, 448kbps

     

    MPEG-1 Audio Layer II: mp2

    Ø  MP2 is a dominant standard for audio broadcasting.

    Ø  Support: 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 192, 224, 256, 320, 384kbps; 16, 22.05, 24, 32, 44.1, 48kHz

    Ø  Support up to 5 full range audio channels and LFE-channel

    Ø  Support mono, stereo, joint stereo, dual channel (uncorrelated) formats.

     

    MPEG-1 Audio Layer III: mp3

    Ø  It is a patented digital audio encoding format for consumer audio storage and for the transfer and playback of music on digital audio players.

    Ø  Support: 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 192, 224, 256 and 320 kbps; 32, 44.1 and 48 kHz

    Ø  The proprietary (unofficial) MPEG-2.5 supports additional 8, 11.025 and 12 kHz.

    Ø  MP3 LAME encoder supports bit rate up to 640kbps.


    MPEG-2

    Ø  It is a standard which describes a combination of lossy video compression and lossy audio data compression methods that permit storage and transmission of movies using currently available storage media and transmission bandwidth.

    Ø  MPEG-2 audio multichannel encoding with up to 5.1 channels.


    MPEG-4

    Ø  It is a patented collection of methods defining compression of audio and video digital data.

    Ø  Key parts of MPEG-4 are MPEG-4 Part 2 and MPEG-4 Part 10 (AVC/H.264).


    PCM: Pulse-code modulation

    Ø  a digital representation of an analog signal where the magnitude of the signal is sampled regularly at uniform. intervals, then quantized to a series of symbols in a numeric (usually binary) code.

    Ø  Compression techniques: DPCM, ADPCM, Delta modulation


    RealVideo

    Ø  RealVideo is a proprietary video format developed by RealNetworks.

    Ø  It is supported on Windows, Mac, Linux, Solaris, and several mobile phones.


    RGB

    Ø  The RGB color model is an additive color model in which red, green and blue light are added together in various ways to reproduce a broad array of colors.

    Ø  Typical RGB input devices are color TV and video cameras, image canners and digital cameras.

    Ø  Typical RGB output devices are TV sets of various technologies (CRT, LCD, plasma. Etc), computer and mobile phone displays, video projectors, etc.


    Sorenson

    Ø  Sorenson codec is a proprietary digital video codec devised by Sorenson Media Inc.

    Ø  It is used in Apple’s QuickTime and Adobe Flash.

    Ø  There are two different proprietary codecs known as: Sorenson video” and “Sorenson Spark” (Sorenson H.263).


    Theora/VP3

    Ø  It is a vbr video compression scheme.

    Ø  It is the successor of On2 VP3.

    Ø  VP3 was originally a proprietary and patented video codec developed by On2 Technologies. On2 then donated VP3 to the Xiph.org Foundation which is the developer of Theora.


     

    VC-1

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