Quantization table adjustment

• US 6,687,407 B2
• Filed: 04/22/2003
• Issued: 02/03/2004
• Est. Priority Date: 12/13/1991
• Status: Expired due to Fees

• Current Assignee: Avid Technology Incorporated
• Original Assignee: Avid Technology Incorporated
• Inventors: Peters, Eric C.
• Primary Examiner(s): Couso, Jose L.
• Application Number:
  US10/420,474
• Publication Number:
  US 20030194137A1
• Time in Patent Office: 287 Days
• Field of Search: 382/232, 382/233, 382/234, 382/238, 382/239, 382/248, 382/250, 382/251, 375/240-2-2, 375/240--24, 375/240-8-2, 375/240-2-2, 348/384.1, 348/394--39, 348/400--40, 348/107--41, 348/420--42, 348/425.2, 348/430--43
• US Class Current: 382/232
• CPC Class Codes: G06F 3/0219 Special purpose keyboards
• CPC Class Codes: G06F 3/0362 with detection of 1D translations or rotations of an operating part of the device, e.g. scroll wheels, sliders, knobs, rollers or belts
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/0489 using dedicated keyboard keys or combinations thereof
• CPC Class Codes: G06F 5/06 for changing the speed of data flow, i.e. speed regularising or timing, e.g. delay lines, FIFO buffers; over- or underrun control therefor G06F7/78 takes precedence
• CPC Class Codes: G06Q 10/10 Office automation; Time management
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/28 by using information signals recorded by the same method as the main recording G11B27/22 takes precedence
• CPC Class Codes: G11B 27/34 Indicating arrangements indicating means incorporated in magazine or cassette G11B23/046 and G11B23/0875; indicating measured values in general G01D
• CPC Class Codes: H04N 19/115 Selection of the code volume for a coding unit prior to coding
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/126 Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/149 by estimating the code amount by means of a model, e.g. mathematical model or statistical model
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/154 Measured or subjectively estimated visual quality after decoding, e.g. measurement of distortion use of rate-distortion criteria H04N19/147
• CPC Class Codes: H04N 19/162 User input
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/60 : using transform coding
• CPC Class Codes: H04N 5/85 : on discs or drums
• CPC Class Codes: H04N 5/907 : using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 5/9264 : using transform coding
• CPC Class Codes: H04N 7/24 : Systems for the transmission of television signals using pulse code modulation H04N21/00 takes precedence
• CPC Class Codes: H04N 9/8042 : involving data reduction

Abstract

The application discloses a media processing method that includes accessing a compressed image data set representing a time series of different compressed video images. These video images have been compressed to differing degrees based on sizes of the compressed video images with a plurality of different quantization tables. The compressed image data set can then be decompressed to retrieve the time series of different video images, and this step of decompressing can be operative independent of information indicating a difference between quantization tables used to compress the images.

Claims

1. A media processing method, comprising:

accessing a compressed image data set representing a time series of different compressed video images that have been compressed to differing degrees based on sizes of the compressed video images with a plurality of different quantization tables and including a first compressed video image compressed with a first quantization table and a second video image compressed with a second quantization table, and

decompressing the compressed image data set to retrieve the time series of different video images, wherein the step of decompressing the compressed image data set includes a step of decompressing the first compressed video image to obtain a first video image and a step of decompressing the second video image to obtain a second video image, and wherein the step of decompressing is operative independent of information indicating a difference between the first and second quantization tables.

2. The method of claim 1 further including the step of editing the time series of video images.

3. The method of claim 2 wherein the step of editing includes introducing transitions between portions of the time series of video images.

4. The method of claim 1 wherein step of decompressing the first compressed video image and the step of decompressing the second compressed video image are each based on a same quantization table.

5. The method of claim 1 wherein the step of accessing accesses a compressed image data set representing a time series of different compressed video images that are compressed to differing degrees by adjusting an extent of quantization.

6. The method of claim 1 wherein the step of accessing accesses a compressed image data set representing a time series of different compressed video images that are compressed to differing degrees by different quantization tables.

7. The method of claim 1 wherein the step of decompressing operates according to a JPEG decompression standard.

8. The method of claim 1 wherein the step of accessing accesses a compressed image data set representing a time series of different compressed digitized video images.

9. The method of claim 1 wherein the step of decompressing includes steps of decoding data from the compressed image data set to produce sets of coefficients and steps of performing inverse transforms on the sets of coefficients to generate the decompressed video images.

10. The method of claim 1 wherein the step of decompressing takes place at a video playback rate for the time series of different video images.

11. The method of claim 10 wherein the step of decompressing takes place at a rate of around 30 frames per second.