broadcast quality video - определение. Что такое broadcast quality video
Diclib.com
Словарь ChatGPT
Введите слово или словосочетание на любом языке 👆
Язык:

Перевод и анализ слов искусственным интеллектом ChatGPT

На этой странице Вы можете получить подробный анализ слова или словосочетания, произведенный с помощью лучшей на сегодняшний день технологии искусственного интеллекта:

  • как употребляется слово
  • частота употребления
  • используется оно чаще в устной или письменной речи
  • варианты перевода слова
  • примеры употребления (несколько фраз с переводом)
  • этимология

Что (кто) такое broadcast quality video - определение

Broadcast-quality

broadcast quality video      
<communications, multimedia> Roughly, video with more than 30 frames per second at a resolution of 800 x 640 pixels. The quality of moving pictures and sound is determined by the complete chain from camera to receiver. Relevant factors are the colour temperature of the lighting, the balance of the red, green and blue vision pick-up tubes to produce the correct display colour temperature (which will be different) and the gamma pre-correction to cancel the non-linear characteristic of cathode-ray tubes in television receivers. The resolution of the camera tube and video coding system will determine the maximum number of pixels in the picture. Different colour coding systems have different defects. The NTSC system (National Television Systems Committee) can produce hue errors. The PAL system (Phase Alternation by Line) can produce saturation errors. Television modulation systems are specified by ITU CCIR Report 624. Low-resolution systems have bandwidths of 4.2 MHz with 525 to 625 lines per frame as used in the Americas and Japan. Medium resolution of 5 to 6.5 MHz with 625 lines is used in Europe, Asia, Africa and Australasia. {High-Definition Television} (HDTV) will require 8 MHz or more of bandwidth. A medium resolution (5.5 MHz in UK) picture can be represented by 572 lines of 402 pixels. Note the ratio of pixels to lines is not the same as the aspect ratio. A VGA display (480n lines of 640 pixels) could thus display 84% of the height of one picture frame. Most compression techniques reduce quality as they assume a restricted range of detail and motion and discard details to which the human eye is not sensitive. Broadcast quality implies something better than amateur or domestic video and therefore can't be retained on a domestic video recorder. Broadcasts use quadriplex or U-matic recorders. The lowest frame rate used for commercial entertainment is the 24Hz of the 35mm cinema camera. When broadcast on a 50Hz television system, the pictures are screened at 25Hz reducing the running times by 4%. On a 60Hz system every five movie frames are screened as six TV frames, still at the 4% increased rate. The six frames are made by mixing adjacent frames, with some degradation of the picture. A computer system to meet international standard reproduction would at least VGA resolution, an interlaced frame rate of 24Hz and 8 bits to represent the luminance (Y) component. For a component display system using red, green and blue (RGB) electron guns and phosphor dots each will require 7 bits. Transmission and recording is different as various coding schemes need less bits if other representations are used instead of RGB. Broadcasts use YUV and compression can reduce this to about 3.5 bits per pixel without perceptible degradation. High-quality video and sound can be carried on a 34 Mbaud channel after being compressed with ADPCM and variable length coding, potentially in real time. (1997-07-04)
Broadcast quality         
Broadcast quality is a term stemming from quad videotape to denote the quality achieved by professional video cameras and time base correctors (TBC) used for broadcast television, usually in standard definition. As the standards for commercial television broadcasts have changed from analog television using analog video to digital television using digital video, the term has generally fallen out of use.
Video quality         
  • No-reference image and video quality assessment methods.
  • Classification of objective video quality models into Full-Reference, Reduced-Reference and No-Reference.
PERCEIVED VIDEO DEGRADATION
Quality video
Video quality is a characteristic of a video passed through a video transmission or processing system that describes perceived video degradation (typically, compared to the original video). Video processing systems may introduce some amount of distortion or artifacts in the video signal that negatively impacts the user's perception of a system.

Википедия

Broadcast quality

Broadcast quality is a term stemming from quad videotape to denote the quality achieved by professional video cameras and time base correctors (TBC) used for broadcast television, usually in standard definition. As the standards for commercial television broadcasts have changed from analog television using analog video to digital television using digital video, the term has generally fallen out of use.

Manufacturers have used it to describe both professional and "prosumer" or "semi-professional" devices. A camera with the minimum requirements typically being the inclusion of three CCDs and relatively low-compression analog recording or digital recording capability with little or no chroma subsampling, and the ability to be genlocked. The advantages of three CCDs include better color definition in shadows, better overall low-light sensitivity, and reduced noise when compared to single-CCD systems. With continuing improvements in image sensors, resolution, recording media, and codecs, by 2006 the term no longer carried much weight in the marketplace.

The term is also used in its literal sense in broadcasting jargon in judging the fitness of audio or video for broadcast.