Method for adaptively encoding motion image based on temporal and spatial complexity and apparatus therefor

• US 7,280,708 B2
• Filed: 02/04/2003
• Issued: 10/09/2007
• Est. Priority Date: 03/09/2002
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Chun, Kang-wook, Song, Byung-cheol
• Primary Examiner(s): Alavi; Amir
• Application Number:
  US10/357,370
• Publication Number:
  US 20030169933A1
• Time in Patent Office: 1,708 Days
• Field of Search: 382/172, 382/218, 382/232, 382/233, 382/236, 382/238, 382/239, 382/250, 382/251, 382/272, 382/299, 382/260, 382/305, 345600-603, 348/400.1, 348/401.1, 348/404.1, 375/240.03, 375/240.08, 375/240.09, 375/240.25
• US Class Current: 382/299
• CPC Class Codes: H04N 19/115 Selection of the code volume for a coding unit prior to coding
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/139 Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability
• CPC Class Codes: H04N 19/14 Coding unit complexity, e.g. amount of activity or edge presence estimation H04N19/146 takes precedence
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/587 involving temporal sub-sampling or interpolation, e.g. decimation or subsequent interpolation of pictures in a video sequence
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A method and an apparatus adaptively encode a motion image based on temporal and/or spatial complexity. In the method, encoding is performed with different temporal and spatial resolutions at frame rates based on the temporal and/or spatial complexity of an input image so that image data is stored with high efficiency. The method includes calculating a spatial complexity of input image data, determining a resolution by comparing the calculated spatial complexity with a predetermined threshold, and converting the resolution of the input image data based on the resolution.

Claims

1. An adaptive image encoding method based on spatial complexity comprising:

calculating a spatial complexity of input image data;

determining a resolution by comparing the spatial complexity with a predetermined threshold; and

determining an outputted resolution of the input image data based on the resolution,

wherein a lower spatial complexity corresponds to a lower resolution.

2. The method of claim 1, wherein the spatial complexity is calculated based on an average dispersion value for each block of the input image data.

3. The method of claim 1, wherein the calculating the spatial complexity and determining the resolution are performed in units of groups of pictures (GOPs) of the input image data.

4. The method of claim 1, wherein the calculating the spatial complexity and determining the resolution are performed in units of sequences of the input image data.

5. The method of claim 1, wherein if the input image data is encoded image data, the spatial complexity is calculated based on decoded data of the input image data.

6. The method of claim 1, wherein if the input image data is encoded image data, the spatial complexity is calculated based on dispersion values obtained from inverse discrete cosine transform (IDCT)-transformed data and motion compensated data.

7. A computer-readable medium having stored thereon computer-executable instructions for performing the method of claim 1.

8. An adaptive image encoding apparatus based on spatial complexity, comprising:

a spatial complexity calculation unit which calculates a spatial complexity of input image data;

a resolution determining unit which determines a resolution by comparing the spatial complexity with a predetermined threshold; and

a resolution converting unit which determines an outputted resolution of input image data based on the resolution,

wherein a lower spatial complexity corresponds to a lower resolution.

9. The apparatus of claim 8, wherein the spatial complexity is calculated based on an average dispersion value for each block of the input image data.

10. The apparatus of claim 8, wherein the calculation of the spatial complexity in the spatial complexity calculation unit and the determination of the resolution in the resolution determining unit are performed in units of groups of pictures (GOPs) of the input image data.

11. The apparatus of claim 8, wherein the calculation of the spatial complexity in the spatial complexity calculation unit and the determination of the resolution in the resolution determining unit are performed in units of sequences of the input image data.

12. The apparatus of claim 8, wherein, if the input image data is encoded image data, the spatial complexity is calculated based on decoded data of the input image data.

13. The apparatus of claim 8, wherein, if the input image data is encoded image data, the spatial complexity is calculated based on dispersion values obtained from IDCT-transformed data and motion compensated data.