Patent application number | Description | Published |
20090060267 | SALIENCE ESTIMATION FOR OBJECT-BASED VISUAL ATTENTION MODEL - The present invention provides a salience estimation method for object-based visual attention model. The method comprises steps of segmenting the image into a plurality of objects to be estimated, extracting feature maps for each segmented object, calculating the saliences of each segmented object in a set of circles defined around a centre pixel of the object based on the extracted feature maps, and integrating the saliences of each segmented object in all circles in order to achieve an overall salience estimation for each segmented object. The present invention is much more human vision inosculated and of low computing complexity. | 03-05-2009 |
20090175330 | Method and apparatus for adapting a default encoding of a digital video signal during a scene change period - The frame following a scene cut is usually coded as an I picture. In CBR encoding, the encoder will try to keep the bit rate constant, which will often cause serious picture quality degradation at scene changes. In VBR encoding, more bits will be allocated to the first frame of the new scene and the bit rate will increase significantly for a short time. Therefore subsequent frames must be coded in ‘skipped’ mode, which will often cause jerk artifacts. According to the invention, in each frame belonging to a scene change period, areas are determined that have different human attention levels. In the frames (n−1, n−2, n−3) located prior to the first new scene frame, to the areas having a lower attention level less bits are assigned than in the default encoding, and in the frames (n, n+1, n+2) located at and after the scene cut the thus saved bits are additionally assigned to the areas having a higher attention level. | 07-09-2009 |
20090245386 | METHOD AND APPARATUS FOR ENCODING A FLASH PICTURE OCCURRING IN A VIDEO SEQUENCE, AND FOR DECODING CORRESPONDING DATA FOR A FLASH PICTURE - When video sequences are obtained from e.g. news, interviews, conferences and sports matches, flashlight often appears in the video due to photographing. When encoding the video sequence, the intensity changes a lot so that the motion estimation can not find a well-matching block in a previous picture. Accordingly, the video encoder will encode in intra mode and thereby generate much more bits than for the neighbouring non-flash pictures. According to the invention, not the real flash picture is encoded in the video sequence but an artificial non-flash or de-flashed picture, and some indications and parameters are inserted into the bit stream to model the flash effect. The decoder can regenerate the flash picture by reconstructing the non-flash picture and then adding the flash effect. The number of bits required for coding flash pictures is thereby significantly reduced. | 10-01-2009 |
20090279603 | Method and Apparatus for Adaptively Determining a Bit Budget for Encoding Video Pictures - When for video coding Intra refresh is used, which inserts Intra coded blocks into previously Inter coded pictures, an efficiently adapted rate control method is required for error resilient video coding. A method for adaptively determining a bit budget for encoding video pictures comprises pre-analyzing each of the pictures of a group of pictures, wherein a relative complexity index is calculated for each picture, allocating bits to the pictures based on their relative complexity index and encoding each of the pictures with the allocated number of bits. The pre-analysis comprises selecting pictures for Intra refresh coding, extracting attention area information from the selected pictures, encoding at least the macroblocks of the attention area using Intra mode, calculating for each picture a complexity index, and calculating from the complexity indices of the pictures of the group a relative complexity index for each picture. Thus, a subjectively better video quality is achieved. | 11-12-2009 |
20100040298 | METHOD AND APPARATUS FOR SELECTING A SCAN PATH FOR THE ELEMENTS OF A BLOCK IN SPATIAL DOMAIN PICTURE ENCODING AND DECODING - International image or video coding standards uses hybrid coding, wherein a picture is separated into pixel blocks on which predictive coding, transform coding and entropy coding is employed. The transform coding is effective because the prediction error samples are correlated in the frequency domain. However, when the prediction quality is getting better and better, spatial domain coding becomes more effective than transform coding. According to the invention, it is first determined in which corner of a current block the first non-zero amplitude value is located. Based on the related zeros run length value in that block, a pre-defined scan path is selected, i.e. a context-based adaptive scan mode is used. | 02-18-2010 |
20100183069 | Method and Apparatus for Determining in Picture Signal Encoding the Bit Allocation for Groups of Pixel Blocks in a Picture - Optimised bit allocation is important in video compression to increase the coding efficiency, i.e. to make optimum use of the available data rate. In view of the human visual system, a human usually pays more attention to some part of a picture rather than to other parts of that picture. Therefore the bit allocation should be optimised for different-attention picture areas (GOB | 07-22-2010 |
20110044386 | METHOD AND APPARATUS FOR ENCODING GROUPS OF PICTURES OF A VIDEO SEQUENCE, EACH OF SAID GROUPS INCLUDING AN INTRA ENCODED PICTURE AND MORE THAN TWO PREDICTED ENCODED PICTURES - In known video coding standards there are basically three types of pictures: I, P and B. Video sequences are usually coded in a group of picture structure wherein several P or B pictures are coded following one I picture. However, this GOP structure has some disadvantages with respect to error resilience and storage medium recording. If a P picture is lost e.g. due to transmission channel error, then the subsequent P pictures can not be reconstructed correctly, and the error will propagate temporally and cause unpleasing artifacts. This GOP structure is designed for forward play only and makes complicated a reverse play operation. According to the invention, a reversible GOP structure is used for the video encoding and decoding. The RGOP structure contains both, a forward encoding chain and a backward encoding chain. Each picture in the RGOP structure is assigned to only one of these chains and the video pictures of adjacent RGOP chains are interleaved. | 02-24-2011 |
20110206356 | METHOD FOR EMBEDDING VIDEO ANNOTATION DATA INTO A CODED VIDEO STREAM AND VIDEO RECORDING DEVICE - The invention concerns a method for embedding video annotation data into a coded video stream. The method comprises the step of—encapsulating said video annotation data into a unit, so-called video annotation unit, of the coded video data stream which format corresponds to at least one format used for sending the associated video data,—inserting an identifiable synchronizing code enabling the identification of said video annotation unit into the video data stream. | 08-25-2011 |
20110317768 | METHOD AND APPARATUS FOR DETERMINING BLUR IN AN IMAGE - Blur is one of the most important features related to video quality. Accurate estimating the blur level of a video is a great help to accurately evaluate the video quality. An improved method is provided for estimating the blur level of videos that are compressed by a block based codec, such as H.264/AVC, MPEG2, etc. According to the invention, local blur detection is based on macroblock (MB) edges, a content dependent weighting scheme is employed to decrease the influence from texture and when detecting local blur, the spreading of detection will stop at local minimum and maximum luminance positions. | 12-29-2011 |
20130070106 | METHOD FOR DETERMINING A QUALITY MEASURE FOR A VIDEO IMAGE AND APPARATUS FOR DETERMINING A QUALITY MEASURE FOR A VIDEO IMAGE - Accurately estimating the image quality of video is still difficult, especially when there is no reference video available. A method for determining a quality measure for a video image comprises selecting a measuring point, such as a MB, determining a context area around the measuring point, calculating a variance of pixel values in the context area, calculating a variance of pixel values in the measuring point, calculating a relation between the two variances of pixel values, and averaging said relations for a plurality of measuring points, wherein a quality measure for a video image is obtained. | 03-21-2013 |
20130211803 | METHOD AND DEVICE FOR AUTOMATIC PREDICTION OF A VALUE ASSOCIATED WITH A DATA TUPLE - The invention relates to a method and a device for automatic prediction of a current value using a weighted average of a number of current reference values, wherein the current value is associated with a current pair consisting of a first and a second current data tuple. The method comprises using a set of reference pairs, each reference pair consisting of a first and a second reference data tuple and being associated with a reference value, for selecting the current reference values wherein the first reference data tuples, the first current data tuple and a first metric is used for selecting, determining, for each current reference value, an associated weight using the second reference data tuples of the pair associated with the respective selected reference value, the second current data tuple and a second metric, and using the current reference values and the determined weights for determining the weighted average. | 08-15-2013 |
20130235214 | METHOD AND APPARATUS FOR MEASURING QUALITY OF VIDEO BASED ON FRAME LOSS PATTERN - A method and apparatus for measuring the quality of a video is provided. The method comprises: generating a frame loss pattern of the video by indicating whether each frame in the video is lost or successfully transmitted; and evaluating the quality of the video as a function of the generated t came loss pattern. | 09-12-2013 |
20140119460 | METHOD AND DEVICE FOR ASSESSING PACKET DEFECT CAUSED DEGRADATION IN PACKET CODED VIDEO - Because of the encoding, decoding, and/or transmitting characteristic, the blocks affected by packet defect usually gather in a small spatial/temporal area. The viewers perception of each affected block will influence by other affected block in this small area. The invention proposes using processing means for clustering blocks affected by the packet loss into at least one cluster, for using at least one of spatial and temporal characteristics of the at least one cluster for determining a visibility value of the at least one cluster, for classifying the at least one cluster as belonging into one of at least two different class candidates, wherein each class candidate is associated with a different weight; for weighting the determined visibility value with the weight associated with the class of the at least one cluster, and for assessing the degradation of the video using a sum of the weighted visibility value. | 05-01-2014 |
20140140612 | USER TERMINAL DEVICE, SERVER DEVICE, SYSTEM AND METHOD FOR ASSESSING QUALITY OF MEDIA DATA - A user terminal device, a server device, a system and a method for assessing quality of media data are described. The user terminal device is used for extracting artefact features from the media data and for communicating the features to the server device which is then used for determining a quality score using the artefacts and an artefact/quality score database accessible by the server device. The score, transmitted to the user terminal device, is presented to a user from which a subjective quality score and a request for re-determination are received which the user terminal device communicates to the server device. This in turn is used for re-determining the quality score and for transmitting back the re-determined quality score wherein the quality score is re-determined using the received artefacts, the received subjective quality score and the artefact/quality score database. | 05-22-2014 |
20140219350 | METHOD AND DEVICE FOR ESTIMATING VIDEO QUALITY ON BITSTREAM LEVEL - A method for estimating video quality on bit-stream level, wherein the video quality refers to a video after error concealment and the method is performed on bit-stream level before said error concealment, comprises extracting and/or calculating a plurality of global condition features from a video bit-stream, extracting and/or calculating a plurality of local effectiveness features at least for a lost MB, calculating a numeric error concealment effectiveness level for each (or at least for each lost) MB by emulating an error concealment method that is used in said error concealment, and providing the calculated error concealment effectiveness level as an estimated visible artifacts level of video quality. | 08-07-2014 |
20140219364 | METHOD AND DEVICE FOR CALCULATING DISTORTION OF A VIDEO BEING AFFECTED BY COMPRESSION ARTIFACTS AND CHANNEL ARTIFACTS - In video quality control and estimation, the joint evaluation of compression artifacts and channel artifacts is a problem. The invention considers the joint perception of both a compression artifact level D | 08-07-2014 |