I-frame code rate control method based on residual frequency domain complexity

A rate control and complexity technology, applied in the field of I frame rate control based on residual frequency domain complexity, can solve I frame complexity measurement and rate model inaccuracy, and limited improvement of I frame rate control effect And other issues

Active Publication Date: 2014-07-30
NANJING UNIV OF POSTS & TELECOMM
View PDF3 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, the intra-frame complexity measurement based on spatial pixel gradient or pixel entropy information does not match the intra-frame coding characteristics of H.264, resulting in inaccurate I-frame complexity measurement and bit rate model, and limited improvement in the effect of I-frame bit rate control

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • I-frame code rate control method based on residual frequency domain complexity
  • I-frame code rate control method based on residual frequency domain complexity
  • I-frame code rate control method based on residual frequency domain complexity

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0044] The invention will be described in further detail below in conjunction with the accompanying drawings.

[0045] Such as figure 1 and figure 2 As shown, the present invention provides a method for controlling the code rate of an I frame based on residual frequency domain complexity, which is specifically a method for controlling the code rate of an H.264 I frame, comprising the steps of:

[0046] 1) Read in the I-frame image to be encoded in the video sequence. If it is the first frame of the sequence, set the initial buffer level to zero, that is, curr_buff_level=0; and set the parameters c and d in the I-frame bit rate model as empirical values.

[0047] 2) Calculate the target number of bits allocated to the current I frame according to the target bit rate, the predefined frame rate and the current buffer level. The formula is as follows:

[0048] R intra = bit _ ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses an I-frame code rate control method based on residual frequency domain complexity. The method includes the steps of reading in an I-frame image, setting the level of an initial buffer area to be zero if the image is the first frame of a sequence, and setting two parameters of an I-frame code rate quantitative model as experience values; calculating a target bit number of the current I-frame according to a target code rate, a frame rate and buffer area fullness; calculating the average absolute value of a frequency domain coefficient of a predicted residual in a brightness component frame to serve as encoding complexity; according to a suggested I-frame code rate-quantitative-complexity model, calculating a quantitative step size; carrying out rate-distortion optimized encoding on the current I-frame through the calculated quantitative step size, and determining the optimal encoding mode of each macro block; if the first frame of the sequence is encoded currently, not needing to update the parameters of the code rate model, using an actual encoding result of the frame encoded before if a second frame of the sequence is encoded, and updating the parameters by means of a linear regression mode; reading in a next I-frame for encoding until all frames of the sequence are encoded.

Description

technical field [0001] The invention relates to the technical field of computer video coding, in particular to an I-frame code rate control method based on residual frequency domain complexity. Background technique [0002] At present, the H.264 standard is widely used in various fields of video coding and transmission due to its high compression efficiency. Bit rate control, as the key technology, adjusts the quantization parameters to make the actual bit rate close to the target bit rate, and at the same time has better video quality, which is an indispensable part of the actual video coding application. However, most of the rate control technologies at present are aimed at P frames, and there are few researches on the rate control technologies of I frames. Existing I-frame bit rate control methods often encode by setting empirical quantization parameters without considering the complexity of I-frame encoding, resulting in poor I-frame bit rate control and sharp fluctuati...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H04N19/124H04N19/147
Inventor 崔子冠干宗良唐贵进刘峰朱秀昌
Owner NANJING UNIV OF POSTS & TELECOMM
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products