Cadence analysis for a video signal having an interlaced format
AssigneeImagination Technologies Limited
InventorPaul Brasnett
Life of this patent
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Abstract
An interlaced video signal can include content of different types, such as interlaced content and progressive content. The progressive content may have different cadences according to the ratio between the frame rate of the progressive content and the field rate of the interlaced video signal. Cadence analysis is performed to identify the cadence of the video signal and/or to determine field pairings when progressive content is included. As described herein, motion information (e.g. motion vectors) for blocks of fields of a video signal can be used for the cadence analysis. The use of motion information provides a robust method of performing cadence analysis.
Claims23
A method of processing a video signal in a video processing unit, the video signal having an interlaced format and comprising a sequence of fields, the method comprising:
- obtaining motion indicators for blocks of a predetermined number of fields of the video signal;
- and
- using the obtained motion indicators to determine cadence signatures for the blocks of said predetermined number of fields, wherein the cadence signatures are indicative of one or more cadences of the video signal;
- creating a histogram of determined cadence signatures of said blocks;
- and
- determining the position of one or more peaks in the histogram to thereby determine one or more significant cadence signatures in the video signal;
- whereby the fields of the video signal are processed in accordance with the determined one or more significant cadence signatures to thereby determine frames of the video signal.
A video processing unit configured to process a video signal, the video signal having an interlaced format and comprising a sequence of fields, the video processing unit being configured to obtain motion indicators for blocks of a predetermined number of fields of the video signal, wherein the video processing unit comprises:
- a cadence analysis module configured to:
- use the obtained motion indicators to determine cadence signatures for blocks of said predetermined number of fields, wherein the cadence signatures are indicative of one or more cadences of the video signal;
- create a histogram of determined cadence signatures of said blocks;
- and
- determine the position of one or more peaks in the histogram to thereby determine one or more significant cadence signatures in the video signal;
- wherein the video processing unit is configured to process the fields of the video signal in accordance with the determined one or more significant cadence signatures to thereby determine frames of the video signal.
A method of processing a video signal in a video processing unit, the video signal having an interlaced format and comprising a sequence of fields, the method comprising:
- obtaining motion indicators for blocks of a predetermined number of fields of the video signal;
- using the obtained motion indicators to determine cadence signatures which are indicative of one or more cadences of the video signal;
- and
- using the determined cadence signatures to identify one or more cadences of the video signal by:
- (i) identifying one or more prevalent cadence signatures from the determined cadence signatures, and (ii) mapping each of the one or more prevalent cadence signatures to a known cadence from a set of known cadences which have known cadence signatures by determining which of the known cadence signatures of the known cadences has a smallest distance to the prevalent cadence signature;
- wherein the fields of the video signal are to be processed in accordance with the identified one or more cadences to thereby determine frames of the video signal.
A video processing unit configured to process a video signal, the video signal having an interlaced format and comprising a sequence of fields, the video processing unit being configured to obtain motion indicators for blocks of a predetermined number of fields of the video signal, wherein the video processing unit comprises:
- a cadence analysis module configured to use the obtained motion indicators to determine cadence signatures which are indicative of one or more cadences of the video signal, and to use the determined cadence signatures to identify one or more cadences of the video signal by:
- (i) identifying one or more prevalent cadence signatures from the determined cadence signatures, and (ii) mapping each of the one or more prevalent cadence signatures to a known cadence from a set of known cadences which have known cadence signatures by determining which of the known cadence signatures of the known cadences has a smallest distance to the prevalent cadence signature,
- wherein the video processing unit is configured to process the fields of the video signal in accordance with the identified one or more cadences to thereby determine frames of the video signal.
A non-transitory computer readable storage medium having stored thereon processor executable instructions that when executed cause at least one processor to process a video signal in a video processing unit, the video signal having an interlaced format and comprising a sequence of fields, the processing of the video signal comprising:
- obtaining motion indicators for blocks of a predetermined number of fields of the video signal;
- and
- using the obtained motion indicators to determine cadence signatures for the blocks, wherein the cadence signatures are indicative of one or more cadences of the video signal;
- creating a histogram of determined cadence signatures of blocks;
- and
- determining the position of one or more peaks in the histogram to thereby determine one or more significant cadence signatures in the video signal;
- wherein the fields of the video signal are to be processed in accordance with the determined one or more significant cadence signatures to thereby determine frames of the video signal.
A non-transitory computer readable storage medium having stored thereon processor executable instructions that when executed at a computer system for generating a representation of a digital circuit from definitions of circuit elements and data defining rules for combining those circuit elements, cause the computer system to generate a video processing unit configured to process a video signal, the video signal having an interlaced format and comprising a sequence of fields, the video processing unit being configured to obtain motion indicators for blocks of a predetermined number of fields of the video signal, wherein the video processing unit comprises:
- a cadence analysis module configured to:
- use the obtained motion indicators to determine cadence signatures for the blocks, wherein the cadence signatures are indicative of one or more cadences of the video signal;
- create a histogram of determined cadence signatures of the blocks;
- and
- determine the position of one or more peaks in the histogram to thereby determine one or more significant cadence signatures in the video signal;
- wherein the video processing unit is configured to process the fields of the video signal in accordance with the determined one or more significant cadence signatures to thereby determine frames of the video signal.
Dependencies are inferred from the claim text.