Progressive video detection with aggregated block SADS
View Patent ↗A method for detecting progressive material in a video sequence is disclosed. The method generally includes the steps of (A) calculating a plurality of block statistics for each of a plurality of blocks in a current field of the video sequence, (B) calculating a plurality of field statistics by summing the block statistics over all of the blocks in the current field, (C) calculating a noise level for the current field based on a subset of the block statistics from each of the blocks and (D) generating a mode flag for the current field based on both (i) the field statistics and (ii) the noise level, wherein the mode flag identifies if the current field is part of a 2:2 pull-down pattern.
1. A method for detecting progressive material in a video sequence, comprising the steps of:
(A) calculating a plurality of block statistics for each of a plurality of blocks in a current field of said video sequence;
(B) calculating a plurality of field statistics by summing said block statistics over all of said blocks in said current field;
(C) calculating a noise level for said current field based on a subset of said block statistics from each of said blocks; and
(D) generating a mode flag for said current field based on both (i) said field statistics and (ii) said noise level, wherein said mode flag identifies if said current field is part of a 2:2 pull-down pattern.
2. The method according to claim 1 , further comprising the step of:
calculating a motion level for said current field based on said subset of said block statistic from each of said blocks, wherein generation of said mode flag is further based on said motion level.
3. The method according to claim 2 , further comprising the step of:
calculating a stationary level for said current field based on said field statistics, wherein (i) said stationary level identifies a stillness in said current field and (ii) generation of said mode flag is further based on said stationary level.
4. The method according to claim 2 , wherein (i) said noise for said current block comprises a minimum among a plurality of sums-of-absolute-differences between a plurality of co-located blocks in a previous field and a next field and (ii) said motion level is based on said sum-of-absolute-differences relative to a plurality of thresholds.
5. The method according to claim 1 , further comprising the step of:
generating a scene change flag for said current field based on a plurality of said field statistics, wherein (i) said scene change flag identifies if said current field is part of a scene change and (ii) generation of said mode flag is further based on said scene change flag.
6. The method according to claim 1 , further comprising the step of:
calculating a plurality of intermediate variables for said current field based on said field statistics.
7. The method according to claim 6 , further comprising the step of:
calculating a plurality of interlacing indicators for said current field based on both (i) said field statistics and (ii) said intermediate variables, wherein said interlacing indicators defining a probability that said current field is part of an interlacing sequence.
8. The method according to claim 6 , further comprising the step of:
calculating a plurality of progressive indicators for said current field based on both (i) said field statistics and (ii) said intermediate variables, wherein said progressive indicators defining a probability that said current field is part of a progressive sequence.
9. The method according to claim 1 , wherein said block statistics comprise a same-parity sum-of-absolute-difference between two co-located areas, one each in a previous field and a next field.
10. The method according to claim 1 , wherein said block statistics comprise two opposite-parity sum-of-absolute-differences between two co-located areas, one each in said current field and a next field.
11. A method for detecting progressive material in a video sequence, comprising the steps of:
(A) calculating a plurality of block statistics for each of a plurality of blocks in a current field of said video sequence;
(B) calculating a plurality of field statistics by summing said block statistics over all of said blocks in said current field;
(C) calculating a motion level for said current field based on a subset of said block statistics from each of said blocks; and
(D) generating a mode flag for said current field based on both (i) said field statistics and (ii) said motion level, wherein said mode flag identifies if said current field is part of a 2:2 pull-down pattern.
12. The method according to claim 11 , further comprising the step of:
calculating a noise level for said current field based on said subset of said block statistics from each of said blocks, wherein generation of said mode flag is further based on said noise level.
13. The method according to claim 11 , further comprising the step of:
calculating a stationary level for said current field based on said field statistics, wherein (i) said stationary level identifies a stillness in said current field and (ii) generation of said mode flag is further based on said stationary level.
14. The method according to claim 11 , further comprising the step of:
generating a scene change flag for said current field based on a plurality of said field statistics, wherein (i) said scene change flag identifies if said current field is part of a scene change and (ii) generation of said mode flag is further based on said scene change flag.
15. The method according to claim 11 , further comprising the step of:
calculating a plurality of intermediate variables for said current field based on said field statistics.
16. The method according to claim 15 , further comprising the step of:
calculating a plurality of interlacing indicators for said current field based on both (i) said field statistics and (ii) said intermediate variables, wherein said interlacing indicators define a probability that said current field is part of an interlacing sequence.
17. The method according to claim 15 , further comprising the step of:
calculating a plurality of progressive indicators for said current field based on both (i) said field statistics and (ii) said intermediate variables, wherein said progressive indicators define a probability that said current field is part of a progressive sequence.
18. The method according to claim 11 , wherein said block statistics comprise two measures of field vertical activity, one each in a previous field and a next field.
19. The method according to claim 11 , wherein said block statistics comprise two opposite-parity sum-of-absolute-differences between two co-located areas, one each in said current field and a previous field.
20. A system comprising:
a memory configured to store a portion of a video sequence; and
a media processor configured to (A) calculate a plurality of block statistics for each of a plurality of blocks in a current field of said video sequence, (B) calculate a plurality of field statistics by summing said block statistics over all of said blocks in said current field, (C) calculate a noise level for said current field based on a subset of said block statistics from each of said blocks, (D) calculate a motion level for said current field based on said subset of said block statistics from each of said blocks and (E) generate a mode flag for said current field based on (i) said field statistics, (ii) said noise level and (iii) said motion level, wherein said mode flag identifies if said current field is part of a 2:2 pull-down pattern.