Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Reduction of errors during computation of inverse discrete cosine transform

A technique for transforming coefficients and arithmetic, used in computer graphics and multimedia

Inactive Publication Date: 2011-04-06
QUALCOMM INC
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Furthermore, errors resulting from mismatches between the encoder's implementation of the IDCT and the decoder's implementation of the IDCT can accumulate during the encoding and decoding of the predicted frame sequence

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
  • Reduction of errors during computation of inverse discrete cosine transform
  • Reduction of errors during computation of inverse discrete cosine transform
  • Reduction of errors during computation of inverse discrete cosine transform

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0047] 1 is a block diagram illustrating an exemplary device 2 for encoding and decoding media files. Apparatus 2 may include a personal computer, mobile radiotelephone, server, network equipment, computer integrated into a vehicle, video game platform, portable video game device, computer workstation, computer kiosk, digital digital signage, mainframe computer, television set-top box, VoIP, personal digital assistant, video game platform, mobile media player, home media player, digital video projector, personal media player (e.g., iPod), or another A type of electronic device.

[0048] Device 2 may include a media source 4 to generate media data. Media source 4 may include a digital video or still photo camera to capture image data. The media source 4 may be built into the device 2, or may be attached to the device 2 as a peripheral device. Media source 4 may also include a microphone to record audio data. Media source 4 may provide media data to processor 6 . Processor ...

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

Techniques are described to reduce rounding errors during computation of discrete cosine transform using fixed-point calculations. According to these techniques, a discrete cosine transform a matrix of scaled coefficients is calculated by multiplying coefficients in a matrix of coefficients by scale factors. Next, a midpoint bias value and a supplemental bias value are added to a DC coefficient of the matrix of scaled coefficients. Next, an inverse discrete cosine transform is applied to the resulting matrix of scaled coefficients. Values in the resulting matrix are then right-shifted in order to derive a matrix of pixel component values. As described herein, the addition of the supplemental bias value to the DC coefficient reduces rounding errors attributable to this right-shifting. As a result, a final version of a digital media file decompressed using these techniques may more closely resemble an original version of a digital media file.

Description

[0001] This application asserts U.S. Provisional Application Nos. 60 / 816,697, filed June 26, 2006, U.S. Provisional Application Nos. 60 / 841,362, filed August 30, 2006, 60 / 847,194, U.S. Provisional Application No. 60 / 829,669, filed October 16, 2006, and U.S. Provisional Application No. 60 / 869,530, filed December 11, 2006, the above provisional applications The entire content of is incorporated herein by reference. technical field [0002] This invention relates to computer graphics and multimedia, and more particularly to the compression of graphics, image and video information. Background technique [0003] Many existing image and video encoding standards use compression techniques in order to allow high resolution images and video to be stored or transmitted as relatively compact files or data streams. Such encoding standards include Joint Photographic Experts Group (JPEG), Moving Pictures Experts Group (MPEG)-1, MPEG-2, MPEG-4 Part 2, H.261, H.263 and Other image or vid...

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
IPC IPC(8): G06F17/14H04N7/30
CPCH04N7/50G06F17/147H04N19/00775H04N19/00781H04N7/2634H04N7/30H04N19/00539H04N19/61H04N19/60H04N19/45H04N19/42H04N19/625
Inventor 哈里纳特·加吕达德里尤里·列兹尼克
Owner QUALCOMM INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products