Comparison of spectrograms of audio in an uncompressed format and several lossy formats. The lossy spectrograms show bandlimiting of higher frequencies, a common technique associated with lossy audio compression.
Block Diagram of HEVC
Solidyne 922: The world's first commercial audio bit compression sound card for PC, 1990
HEVC has 33 intra prediction modes
Processing stages of a typical video encoder

In comparison to AVC, HEVC offers from 25% to 50% better data compression at the same level of video quality, or substantially improved video quality at the same bit rate.

- High Efficiency Video Coding

It has since been applied in various other designs including H.263, H.264/MPEG-4 AVC and HEVC for video coding.

- Data compression
Comparison of spectrograms of audio in an uncompressed format and several lossy formats. The lossy spectrograms show bandlimiting of higher frequencies, a common technique associated with lossy audio compression.

10 related topics with Alpha

Overall

Advanced Video Coding

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Video compression standard based on block-oriented, motion-compensated coding.

Video compression standard based on block-oriented, motion-compensated coding.

Block diagram of H.264
A YouTube video statistics with AVC (H.264) video codec and Opus audio format

High Efficiency Video Coding (HEVC), a.k.a. H.265 and MPEG-H Part 2 is a successor to H.264/MPEG-4 AVC developed by the same organizations, while earlier standards are still in common use.

AVC-Intra is an intraframe-only compression format, developed by Panasonic.

Nasir Ahmed, the inventor of the discrete cosine transform (DCT), which he first proposed in 1972.

Discrete cosine transform

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A discrete cosine transform (DCT) expresses a finite sequence of data points in terms of a sum of cosine functions oscillating at different frequencies.

A discrete cosine transform (DCT) expresses a finite sequence of data points in terms of a sum of cosine functions oscillating at different frequencies.

Nasir Ahmed, the inventor of the discrete cosine transform (DCT), which he first proposed in 1972.
Illustration of the implicit even/odd extensions of DCT input data, for N=11 data points (red dots), for the four most common types of DCT (types I-IV).
336x336px
An example showing eight different filters applied to a test image (top left) by multiplying its DCT spectrum (top right) with each filter.
Original size, scaled 10x (nearest neighbor), scaled 10x (bilinear).
Basis functions of the discrete cosine transformation with corresponding coefficients (specific for our image).
 DCT of the image =
.
On the left is the final image. In the middle is the weighted function (multiplied by a coefficient) which is added to the final image. On the right is the current function and corresponding coefficient. Images are scaled (using bilinear interpolation) by factor 10×.

The DCT, first proposed by Nasir Ahmed in 1972, is a widely used transformation technique in signal processing and data compression.

The integer DCT is used in Advanced Video Coding (AVC), introduced in 2003, and High Efficiency Video Coding (HEVC), introduced in 2013.

Video coding format

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Content representation format for storage or transmission of digital video content (such as in a data file or bitstream).

Content representation format for storage or transmission of digital video content (such as in a data file or bitstream).

It typically uses a standardized video compression algorithm, most commonly based on discrete cosine transform (DCT) coding and motion compensation.

Examples of video coding formats include H.262 (MPEG-2 Part 2), MPEG-4 Part 2, H.264 (MPEG-4 Part 10), HEVC (H.265), Theora, RealVideo RV40, VP9, and AV1.

Lossy compression

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In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content.

High Efficiency Video Coding (HEVC / H.265)

MPEG logo

Moving Picture Experts Group

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MPEG logo
Some well known older (up to 2005) digital media formats and the MPEG standards they use

The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and file formats for various applications.

It was created in 2010 to develop High Efficiency Video Coding (HEVC, MPEG-H Part 2, ITU-T H.265), a video coding standard that further reduces by about 50% the data rate required for video coding, as compared to the then-current ITU-T H.264 / ISO/IEC 14496-10 standard.

MPEG-4 Part 2

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Video compression format developed by the Moving Picture Experts Group (MPEG).

Video compression format developed by the Moving Picture Experts Group (MPEG).

Most of the video compression schemes standardize the bitstream (and thus the decoder) leaving the encoder design to the individual implementations.

The quarter-pixel motion compensation feature of ASP was innovative, and was later also included (in somewhat different forms) in later designs such as MPEG-4 Part 10, HEVC, VC-1 and VVC.

A photo of a European wildcat with the compression rate decreasing and hence quality increasing, from left to right

JPEG

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Commonly used method of lossy compression for digital images, particularly for those images produced by digital photography.

Commonly used method of lossy compression for digital images, particularly for those images produced by digital photography.

A photo of a European wildcat with the compression rate decreasing and hence quality increasing, from left to right
The 8×8 sub-image shown in 8-bit grayscale
Zigzag ordering of JPEG image components
This image shows the pixels that are different between a non-compressed image and the same image JPEG compressed with a quality setting of 50. Darker means a larger difference. Note especially the changes occurring near sharp edges and having a block-like shape.
The original image
The compressed 8×8 squares are visible in the scaled-up picture, together with other visual artifacts of the lossy compression.
Visual impact of a jpeg compression on Photoshop on a picture of 4480x4480 pixels
An example of a stereoscopic .JPS file

In video compression MCUs are called macroblocks.

The standard is expected to exceed the still image compression performance shown by HEVC HM, Daala and WebP, and unlike previous efforts attempting to replace JPEG, to provide lossless more efficient recompression transport and storage option for traditional JPEG images.

Inter-frame prediction process. In this case, there has been an illumination change between the block at the reference frame and the block which is being encoded: this difference will be the prediction error to this block.

Inter frame

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Inter-frame prediction process. In this case, there has been an illumination change between the block at the reference frame and the block which is being encoded: this difference will be the prediction error to this block.
Illustration of dependencies of the group of pictures scheme IBBPBB... Time goes from left to right.
400px

An inter frame is a frame in a video compression stream which is expressed in terms of one or more neighboring frames.

However, in newer encoding methods (such as H.264/MPEG-4 AVC and HEVC), B-frames may be used as reference for better exploitation of temporal redundancy.

Reverse side of a Blu-ray. Unlike CD and DVD, the reflection has a blue hue. Different brands of disc can have different colors, such as silver, gold, or grey.

Blu-ray

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Digital optical disc storage format.

Digital optical disc storage format.

Reverse side of a Blu-ray. Unlike CD and DVD, the reflection has a blue hue. Different brands of disc can have different colors, such as silver, gold, or grey.
Reverse side of a Blu-ray. Unlike CD and DVD, the reflection has a blue hue. Different brands of disc can have different colors, such as silver, gold, or grey.
A blank rewritable Blu-ray Disc (BD-RE)
Kees Schouhamer Immink received a personal Emmy award for his pioneering contributions to the DVD and the Blu-ray Disc.
Blu-ray case (often blue-tinted)
Front of an experimental 200 GB rewritable Blu-ray Disc
Early 4K Blu-ray release at Best Buy. A 4K Blu-ray Disc player was also released.
Comparison of several forms of disc storage showing tracks (not to scale); green denotes start and red denotes end.
 Some CD-R(W) and DVD-R(W)/DVD+R(W) recorders operate in ZCLV, CAA or CAV modes.
Comparison of various optical storage media
100 GB BDXL triple-layer disc by Sharp
The AACS decryption process
A Panasonic Blu-ray player DMP-BD60 (late 2009) compatible with AVCHD
The Blu-ray 3D logo
Regions for the Blu-ray Disc standard: 
Region A/1
Region B/2
Region C/3

It was to offer MPEG-2, MPEG-4 AVC (H.264), HEVC (H.265), and VC-1 encoding, supporting a maximum storage capacity of 6TB.

Players may optionally implement Dolby Digital Plus and DTS-HD High Resolution Audio as well as lossless formats Dolby TrueHD and DTS-HD Master Audio.

Motion vectors that result from a movement into the z-plane of the image, combined with a lateral movement to the lower-right. This is a visualization of the motion estimation performed in order to compress an MPEG movie.

Motion estimation

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Process of determining motion vectors that describe the transformation from one 2D image to another; usually from adjacent frames in a video sequence.

Process of determining motion vectors that describe the transformation from one 2D image to another; usually from adjacent frames in a video sequence.

Motion vectors that result from a movement into the z-plane of the image, combined with a lateral movement to the lower-right. This is a visualization of the motion estimation performed in order to compress an MPEG movie.
Video frames with motion interpolation

As a way of exploiting temporal redundancy, motion estimation and compensation are key parts of video compression.

Almost all video coding standards use block-based motion estimation and compensation such as the MPEG series including the most recent HEVC.