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  • H04N19/50—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
  • H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
  • H04N19/51—Motion estimation or motion compensation
  • H04N19/577—Motion compensation with bidirectional frame interpolation, i.e. using B-pictures
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  • H04N19/189—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding
  • H04N19/19—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding using optimisation based on Lagrange multipliers
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  • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
  • H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
  • H04N19/103—Selection of coding mode or of prediction mode
  • H04N19/105—Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
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  • H04N19/142—Detection of scene cut or scene change
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  • H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
  • H04N19/146—Data rate or code amount at the encoder output
  • H04N19/147—Data rate or code amount at the encoder output according to rate distortion criteria
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  • H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
  • H04N19/157—Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter
  • H04N19/159—Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
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  • H04N19/169—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
  • H04N19/17—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object
  • H04N19/176—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
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  • H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
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  • H04N19/52—Processing of motion vectors by encoding by predictive encoding
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  • H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
  • H04N19/51—Motion estimation or motion compensation
  • H04N19/573—Motion compensation with multiple frame prediction using two or more reference frames in a given prediction direction
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  • H04N19/60—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding
  • H04N19/61—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding

Definitions

• the present principles relate generally to video encoding and, more particularly, to a method and apparatus for adaptive weight selection for motion compensated prediction.
• Video compression encoders and/or decoders gain much of their compression efficiency by forming a reference picture prediction of a picture to be encoded, and only encoding the difference between the current picture and the prediction. The more closely correlated the prediction is to the current picture, the fewer the bits needed to compress that picture. This prediction can be generated by using either spatial or temporal samples within previously available pictures or blocks.
• Temporal prediction is essentially performed through the consideration of motion parameters that may be available within the bitstream and, optionally, weighting/offsetting parameters which are either explicitly encoded or implicitly derived from the bitstream. Weighting and offsetting parameters can be rather useful in the presence of certain transitions such as fades and cross-fades, and could lead to considerably improved performance compared to traditional motion compensated schemes.
• the International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) Moving Picture Experts Group-4 (MPEG-4) Part 10 Advanced Video Coding (AVC) standard/International Telecommunication Union, Telecommunication Sector (ITU-T) H.264 recommendation (hereinafter the "MPEG-4 AVC standard") provides a weighted prediction tool with two modes, an explicit mode and an implicit mode. In the explicit mode, the encoder may select and properly assign the weights and offsets used in encoding and decoding.
• the MPEG-4 AVC standard does not suggest or require any particular method for selecting these weights and offsets.
• weighting parameters are computed based on "temporal" distances between pictures. For determining such distances, each picture/slice is associated with a counter field referred to as the Picture Order Count (POC), which can also be used for display purposes.
• POC Picture Order Count
• Implicit mode is only available for B slices, while a rather important differentiation between these two modes is that for B slices for explicit mode the same weights are applied for both single and bi prediction, while implicit weights are applied only for bi prediction.
• weight estimation may consider statistical approaches like linear regression, estimating weighting parameters as the ratio between the average value of the pixels in the current picture divided by the average value of the pixels in the reference picture, histogram methods, and weighted parameter estimation in the presence of cross-fades using displaced differences.
• weights are refined by considering the current source picture and the motion predicted non-weighted reference picture. This process is repeated until it converges or satisfies an end criteria/criterion.
• multiple reference pictures can be used for inter-prediction, with a reference picture index coded to indicate which of the multiple reference pictures is used.
• P slices only single prediction is used, and the allowable reference pictures are managed in list 0.
• B slices two reference picture lists are considered, list 0 and list 1.
• prediction can be performed using single prediction by considering either list 0 or list 1 , or bi-prediction using both list 0 and list 1.
• the list 0 and the list 1 predictors are averaged together to form a final predictor.
• B pictures may be stored and used as reference pictures when coding other pictures.
• the MPEG-4 AVC standard uses tree-structured hierarchical macroblock partitions. Inter-coded 16x16 pixel macroblocks can be broken down into macroblock partitions, of sizes 16x16, 16x8, 8x16, or 8x8. 8x8 macroblock partitions are also known as sub-macroblocks, and may also be broken into sub-macroblock partitions, of sizes 8x4, 4x8, and 4x4.
• a reference picture index, prediction type (list 0, list 1 , bipred), and a motion vector may be independently selected and coded.
• a motion vector may be independently selected and coded, but the reference picture index and prediction type of the sub-macroblock is used for all of the sub-macroblock partitions.
• the MPEG-4 AVC standard does not use a temporal reference in the Video Coding Layer (VCL), but instead uses Picture Order Count (POC) to indicate relative distances between coded pictures.
• POC Picture Order Count
• Several methods are provided for coding the picture order count of each slice, including coding of a delta_pic_order_cnt field in the slice header.
• POC is used for scaling of motion vectors in direct mode, and for weighting factor derivation in weighted prediction (WP) implicit mode. Weighted prediction is supported in the Main and Extended profiles of the
• MPEG-4 AVC standard Use of weighted prediction is indicated in the sequence parameter set for P and SP slices using the weighted_pred_flag field, and for B slices using the weighted_bipred_idc field.
• WP modes There are two WP modes, an explicit mode which is supported in P, SP, and B slices, and an implicit mode which is supported in B slices only.
• the weighting factor used is based on the reference picture index (or indices in the case of bi-prediction) for the current macroblock or macroblock partition.
• the reference picture indices are either coded in the bitstream or may be derived, e.g., for skipped or direct mode macroblocks.
• explicit mode these parameters are coded in the slice header.
• implicit mode these parameters are derived.
• the weighting factors and offset parameter values are constrained to allow for 16 bit arithmetic operations in the inter prediction process.
• Explicit mode is indicated by weighted_pred_flag equal to 1 in P or SP slices, or by weighted_bipred_idc equal to 1 in B slices.
• the WP parameters are coded in the slice header.
• a multiplicative weighting factor and an additive offset for each color component may be coded for each of the allowable reference pictures in list 0 for P slices and B slices.
• the number of allowable reference pictures in list 0 is indicated by num_refjdx_l ⁇ _active_minus1
• for list 1 for B slices is indicated by num_ref_idx_l1_active_minus1.
• the dynamic range and precision of the weighting factors can be adjusted using the Iuma_log2_weight_denom and chroma_log2_weight_denom fields, which are the binary logarithm of the denominator of the luma and chroma weighting factors, respectively. Higher values of the log weight denominator allow more finegrained weighting factors but require additional bits for coding the weighting factors and limit the range of the effective scaling. For each allowable reference picture index in list 0, and for B slices also in list 1 , flags are coded to indicate whether or not weighting parameters are present in the slice header for that reference picture index, separately for the luma and chroma components.
• weighting parameters are not present in the slice header for a given reference picture index and color component, a default weighting factor equivalent to a scaling factor of 1 and a zero offset are used.
• the multiplicative weighting factors are coded as luma_weight_IO, Iuma_weight_l1 , chroma_weight_IO, and chroma_weight_J1.
• the additive offsets are coded as luma_offset_IO, Iuma_offset_l1 , chroma_pffsetJ0, and chroma_offset_l1.
• MMCO memory management control operation
• RPLR reference list picture reordering
• the same weighting parameters that are used for single prediction are used in combination for bi-prediction.
• the final inter prediction is formed for the pixels of each macroblock or macroblock partition, based on the prediction type used.
• SampleP which denotes the weighted predictor, is calculated as follows:
• SampleP Clip1(((SampleP0-W 0 + 2 LWD - 1 ) »LWD)+O 0 ), and for single prediction from list 1 ,
• SampleP Clip1(((SampleP1 -lVi + 2 LWD'1 ) »LWD) +O 1 ),
• SampleP Clip1(((SampleP0-H/ 0 + Sampl ⁇ P1 -W ⁇ + 2 LWD ) » (LWD+1 )) + (O 0 + O 1 + 1 )»1 )
• Clip1 () is an operator that clips to the range [0, 255]
• W 0 and O 0 are the list 0 reference picture weighting factor and offset
• W 1 and O ? are the list 1 reference picture weighting factor and offset
• LWD is the log weight denominator rounding factor.
• SamplePO and SamplePI are the list 0 and list 1 initial predictors.
• the Joint Video Team (JVT) JM reference software includes a method of selecting weights and always assigns a value of zero to the offsets.
• JM software method while coding a picture, the mean values , M 1 , of the Y, U, and V color components of all pixels in the current picture are calculated, where / is the color component index.
• mean values, MRy, of the Y, U, and V components of each pixel in each of the allowable reference pictures are calculated, where/ is the reference picture index.
• An estimated multiplicative weighting factor, Wjj, for each color component of each reference picture is computed as the ratio of the mean of the current picture to the mean of the reference picture, scaled by a left shift of the log weight denominator, as follows:
• weighting factors are not explicitly transmitted in the slice header, but instead are derived based on relative distances between the current picture and the reference pictures. Implicit mode is used only for bi-predictively coded macroblocks and macroblock partitions in B slices, including those using direct mode. The same formula for bi-prediction is used, except that the offset values O 0 and Oi are equal to zero, and the weighting factors W 0 and W 1 are derived using the formulas below.
• TD B is temporal difference between the list 1 reference picture and the list 0 reference picture, clipped to the range [-128, 127]
• TD B is difference of the current picture and the list 0 reference picture, clipped to the range [-128, 127].
• SampleP SampleP0-wb + oi
• SampleP (SamplePO-Wo + SamplePI -W 1 + ⁇ o + o ⁇ i
• an apparatus includes an encoder for encoding a picture by deriving a set of weighting parameters, selecting at least one weighting parameter in the set based upon a selection criteria, and applying the selected at least one weighting parameter to a reference picture used to encode the picture.
• a video encoding method includes encoding a picture by deriving a set of weighting parameters, selecting at least one weighting parameter in the set based upon a selection criteria, and applying the selected at least one weighting parameter to a reference picture used to encode the picture.
• FIG. 1 shows a diagram for an exemplary video encoder, which incorporates weights estimation, to which the present principles may be applied, in accordance with an embodiment of the present principles
• FIG. 2 shows a diagram for an exemplary method for selecting the best weighted prediction method for single prediction, in accordance with an embodiment of the present principles
• FIG. 3 shows a diagram for an exemplary method for selecting the best weighted prediction method for single prediction and bi-prediction, in accordance with an embodiment of the present principles.
• the present principles are directed to a method and apparatus for adaptive weight selection for motion compensated prediction.
• processor or “controller” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (“DSP”) hardware, read-only memory (“ROM”) for storing software, random access memory (“RAM”), and non-volatile storage.
• DSP digital signal processor
• ROM read-only memory
• RAM random access memory
• any switches shown in the figures are conceptual only. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the implementer as more specifically understood from the context.
• any element expressed as a means for performing a specified function is intended to encompass anv wav of oerformin ⁇ that function including, for example, a) a combination of circuit elements that performs that function or b) software in any form, including, therefore, firmware, microcode or the like, combined with appropriate circuitry for executing that software to perform the function.
• the present principles as defined by such claims reside in the fact that the functionalities provided by the various recited means are combined and brought together in the manner which the claims call for. It is thus regarded that any means that can provide those functionalities are equivalent to those shown herein.
• FIG. 1 an exemplary video encoder which incorporates weights estimation is indicated generally by the reference numeral 100.
• a non-inverting input of a combiner 105, a first input of a Mode Decision (MD) & Motion Compensation (MC) 175, a first input of a motion estimator (ME) 165, and a first input of a motion estimator 170 are available as inputs to the video encoder.
• An output of the combiner 105 is connected in signal communication with an input of a transformer 110.
• An output of the transformer 110 is connected in signal communication with an input of a quantizer 115.
• An output of the quantizer 115 is connected in signal communication with an input of a variable length coder (VLC) 120.
• VLC variable length coder
• An output of the VLC 120 is available as an output of the video encoder 100.
• the output of the quantizer 115 is also connected in signal communication with an input of an inverse quantizer 125.
• An output of the inverse quantizer 125 is connected in signal communication with an input of an inverse transformer 130.
• An output of the inverse transformer 130 is connected in signal communication with a first non-inverting input of a combiner 180.
• An output of the combiner 180 is connected in signal communication with an input of a loop filter 135.
• An output of the loop filter 135 is connected in signal communication with an input of a picture reference store 140.
• An output of the reference picture store 140 is connected in signal communication with an input of a ListO reference buffer 145 and with an input of a List 1 reference buffer 150.
• a first outDut of the ListO reference buffer 145 is connected in signal communication with a first input of multiplier 155.
• a first output of the Listi reference buffer 150 is connected in signal communication with a first input of a multiplier 160.
• a second output of the ListO reference buffer 145 and a second output of the Listi reference buffer 150 are connected in signal communication with a second input of the MD&MC 175.
• An output of the multiplier 155 is connected in signal communication with a second input of the motion estimator 165.
• An output of the multiplier 160 is connected in signal communication with a second input of the motion estimator 170.
• a first output of the MD&MC 175 is connected in signal communication with an inverting input of the combiner 105.
• a second output of the MD&MC 175 is connected in signal communication with a second non-inverting input of the combiner 180.
• a method and apparatus are provided that allow for determining the most appropriate weighting method(s) for encoding a current picture. Furthermore, in accordance with an embodiment of the present principles, the determination of the explicit weighting parameters can be improved by considering multiple weight estimation methods. In accordance with an embodiment of the present principles, different weighting factors are initially estimated using various methods. These weights, which could include normal, implicit, and multiple explicit weights, are then evaluated by considering simple criteria or methods, such as correlation or distortion computation, and the most appropriate weight and weighting method(s) according to such criteria is selected for encoding the current picture/slice.
• an embodiment of the present principles allows for the efficient selection between explicit and implicit modes, since, potentially either one could provide different benefits.
• the implicit mode may provide better performance in the presence of only local brightness transformations, or during linear fades, while explicit mode may be more useful during cross-fades.
• the implicit mode may itself be useful for improving coding efficiency of non-fading frames considering that single prediction does not use weights, while bi- prediction allows for a more efficient exploiting of the higher correlation that may exist with references closer in time.
• weighted prediction WP
• WP weighted prediction
• various algorithms are known for estimating the explicit weighting parameters, we contend that different computation methods could be more beneficial or accurate for certain types of transitions. Therefore, in accordance with the present principles, various embodiments are provided that not only improve the weight parameter selection, but also make a better decision with regard to the WP method that is to be used.
• picture correlation metrics refers to either field or frame pictures according to the picture structure decision.
• a set of picture correlation metrics needs to be computed according to the slice type or prediction method that is used.
• P slices single inter-prediction
• W 0 is the weight for this reference, and O ⁇ ,, is the corresponding offset.
• F cur corresponds to the current picture, and Frefj is the reference with index i.
• the mean essentially computes the average of all pixels within F cur . Note that computation could also be based on DC images, or even sub-sampled images in order to reduce complexity if needed.
• a distortion metric compared to the current picture is also computed which is referred to herein as sum_diff_wfo,/ . This distortion metric will be described further later. It is apparent that this case is used in order to consider multiplicative transitions.
• a distortion metric compared to the current picture is also computed which is referred to herein as sum_diff_woo,/ This case is considered for additive transitions.
• weighting parameter selection for each reference in each list is made similar to the single prediction case, without jointly considering the impact of other references.
• the selected weighting parameters from this decision will then be considered in a second step which considers joint weight optimization.
• Case 1 w x , and o x ⁇ l for both lists are pre-selected from sub-case 1 through sub-case
• Case 2 involves the consideration of joint correlation through computation of
• Weights are computed implicitly.
• each one of the possible weighting candidates described above results in one factor/offset couple for single prediction and two for bi-predictions.
• the distortion based on difference of histograms is used.
• the histogram distortions can then be used to determine which method is most likely superior in terms of single prediction.
• the present principles are not limited to solely the use of histogram distortions and, thus, other distortion metrics may also be used in accordance with the principles.
• one other such distortion metric includes, but is not limited to, absolute difference.
• Selection can also be based on the successful detection of the current transition, while due to the consideration that the use of no WP might be more appropriate at times, a different priority for such distortion is considered when comparing to the weighted distortions. More specifically, adaptive selection for single prediction can be described in the following pseudo code (as well as the method 200 of FIG. 2 below):
• min_sum_diff sum_diff_wf
• min_log_weight_denom log_weight_denom
• min_weight_f actor weight_factor
• min_weight_offset 0;
• min_sum_diff sum_diff_wo
• min_Jog_weight_denom default_log_weight_denom
• min_weight_factor default_weight
• min_weight_offset weight_offset
• min_sum_diff sum_diff_nowp
• min_log_weight_denom default_log_weight_denom
• min_weight_factor default_weight
• min_weight_pffset 0;
• method 2 weights are considered during motion estimation from combined references and the final mode decision and encoding. Motion estimation from normal references may be performed using the best of the three other methods.
• weighted prediction estimation methods e.g., histogram approach, iterative schemes, and so forth
• the method 200 includes a start block 205 that passes control to a function block 210.
• the function block 210 computes the weights, sum_diff_wo, sum_diff_wf, and sum_diff_nowp, and passes control to a decision block 215.
• the decision block 215 determines whether or not sum_diff_wo is less than sum_diff_wf. If so, then control is passed to a function block 220. Otherwise, control is passed to a function block 225.
• the function block -220 sets the best mode to offsets, sets the best_sum to sum_diff_wo, and passes control to a decision block 230.
• the function block 225 sets the best_mode to weights, sets the best_sum to sum_diff_wf, and passes control to a decision block 230.
• the decision block 230 determines whether or not best_sum is less than Ts*sum_diff_nowp. If so, then control is passed to 240. Otherwise, control is passed to 235.
• the function block 235 sets the best_mode to nowp, sets the best_sum to sum_diff_nowp, and passes control to an end block 240.
• an exemplary method for selecting the best weighted prediction method for single prediction and bi-prediction is indicated generally by the reference numeral 300.
• the method 300 includes a start block 305 that passes control to a function block 310.
• the function block 310 computes the weights and distortions, and passes control to a decision block 315.
• the decision block 315 determines whether or not the scene transition is fade or cross_fade. If so, then control is passed to a function block 325. Otherwise, control is passed to a decision block 320.
• the decision block 325 determines whether or not bi-prediction is to be used. If so, then control is passed to a function block 335. Otherwise, control is passed to a decision block 340.
• the decision block 335 determines whether or not dist caS e2 ⁇ c * min(dist n owp,dist im p,distcasei). If so, then control is passed to a function block 360. Otherwise, control is passed to a decision block 350.
• the function block 360 sets the best_mode to exp_mode2, and passes control to an end block 380.
• the decision block 350 determines whether or not dist ca sei ⁇ d * min(distn o wp,distim P ). If so, then control is passed to a function block 365. Otherwise, control is passed to a decision block 355.
• the function block 365 sets the best_mode to exp_mode1 , and passes control to the end block 380.
• the decision block 355 determines whether or not distj mp ⁇ e* dist n0W p- If so, the control is passed to a function block 375. Otherwise, control is passed to a function block 370.
• the function block 375 sets the best_mode to implicit, and passes control to the end block 380.
• the function block 370 sets the bestjmode to nowp, and passes control to the end block 380.
• the decision block 320 determines whether or not bi-prediction is to be used. If so, then control is passed to a decision block 330. Otherwise, control is passed to the function block 370.
• the decision block 330 determines whether or not distj mp ⁇ a * dist nO wp- If so, then control is passed to the function block 375. Otherwise, control is passed to the function block 370.
• the decision block 340 determines whether or not dist exp 2 ⁇ b* min(distnowp,distex P i). If so, then control is passed to the function block 360. Otherwise, control is passed to the decision block 345.
• one advantage/feature is an apparatus that includes an encoder for encoding a picture by deriving a set of weighting parameters, selecting at least one weighting parameter in the set based upon a selection criteria, and applying the selected at least one weighting parameter to a reference picture used to encode the picture.
• Another advantage/feature is the apparatus having the encoder as described above, wherein the encoder selects the at least one weighting parameter in the set based upon a full encoding of the picture with each of the weighting parameters in the set and using rate distortion optimization.
• Yet another advantage/feature is the apparatus having the encoder that uses the rate distortion optimization as described above, wherein the rate distortion optimization is performed using Lagrangian multipliers.
• another advantage/feature is the apparatus having the encoder as described above, wherein the encoder selects the at least one weighting parameter based upon a computation of a distortion metric. Further, another advantage/feature is the apparatus having the encoder that selects the at least one weighting parameter based upon the computation of the distortion metric as described above, wherein the distortion metric is computed as an absolute picture difference between the picture and a weighted reference picture. Also, another advantage/feature is the apparatus having the encoder that selects the at least one weighting parameter based upon the computation of the distortion metric as described above, wherein the distortion metric is computed as a difference between histograms of the picture and a weighted reference picture.
• another advantage/feature is the apparatus having the encoder that selects the at least one weighting parameter based upon the computation of the distortion metric as described above, wherein the encoder uses at least one of histogram methods, picture mean averages, linear regression, displaced differences, and iterative methods to estimate explicit weighting parameters for the picture.
• Yet another advantage/feature is the apparatus having the encoder as described above, wherein the encoder also selects an optimal weighting method to encode the picture based on distortion characterization, the optimal weighting method selected from among a non-weighted prediction method, an explicit weighted prediction method, and an implicit weighted prediction method, each included in the set of weighting parameters.
• the apparatus having the encoder that also selects the optimal weighting method as described above wherein the distortion characterization involves bi-prediction distortion computed based on both list 0 and list 1 reference pictures.
• another advantage/feature is the apparatus having the encoder that also selects the optimal weighting method as described above, wherein the encoder selects the optima! weighting method to encode the picture using at least one transition detection method.
• the teachings of the present principles are implemented as a combination of hardware and software.
• the software may be implemented as an application program tangibly embodied on a program storage unit.
• the application program may be uploaded to, and executed by, a machine comprising anv suitable architecture.
• the machine is implemented on a computer platform having hardware such as one or more central processing units (“CPU"), a random access memory (“RAM”), and input/output ("I/O") interfaces.
• CPU central processing units
• RAM random access memory
• I/O input/output
• the computer platform may also include an operating system and microinstruction code.
• the various processes and functions described herein may be either part of the microinstruction code or part of the application program, or any combination thereof, which may be executed by a CPU.
• various other peripheral units may be connected to the computer platform such as an additional data storage unit and a printing unit.

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• Engineering & Computer Science (AREA)
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• Signal Processing (AREA)
• Compression Or Coding Systems Of Tv Signals (AREA)

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• 2007
  • 2007-01-31 JP JP2008553311A patent/JP5224459B2/ja not_active Expired - Fee Related
  • 2007-01-31 KR KR1020087018313A patent/KR101406156B1/ko not_active Expired - Fee Related
  • 2007-01-31 WO PCT/US2007/002563 patent/WO2007092215A2/en not_active Ceased
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  • 2007-01-31 CN CN200780004391.2A patent/CN101379829B/zh not_active Expired - Fee Related
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