Abstract: A method is proposed of selection, for a current image portion to be encoded and for at least one encoding module included in a video encoder, of at least one encoding parameter from amongst a set of encoding parameters available for the at least one encoding module. The method is based on a decision model defining a minimization, under a rate constraint, of a first measurement of distortion between source samples, included in the current image portion to be encoded, and current reconstructed samples, included in a current reconstructed image portion, obtained from the current image portion to be encoded. The decision model defines the minimization under an additional smoothness constraint, pertaining to a second measurement of distortion between the current reconstructed samples and preceding reconstructed samples, belonging to a temporal reference neighborhood comprising at least one preceding reconstructed image portion obtained from at least one preceding encoded image portion.

Abstract: A first splicer manages a get-list request coming from a player and parameterized with an identifier of a first content and a group identifier. The first splicer obtains an initial playlist having a first URI template, pointing towards a first server and pre-parameterized with the identifier of the first content, and a first list of segment identifiers. The first splicer builds and transmits a final playlist to the player including a second URI template, pointing to a second splicer and pre-parameterized with the identifier of the first content and the group identifier, and a second list of virtual segment identifiers. Each virtual segment is associated with a segment of the first content or of an alternative content.

Abstract: A system is proposed for dynamic reduction of the entropy of a signal upstream to a data compression device. The signal includes a set of successive frames. The system has a filtering decision module that provides a setpoint value of filtering and a filtering module that filters the signal according to the setpoint value of filtering and gives a filtered signal to the data compression device. The system further includes a module for obtaining a piece of information on complexity for each frame of the signal. The filtering decision module is adapted to determining the setpoint value of filtering, for each frame of the signal, as a function inter alia of the piece of information on complexity.

Abstract: A real time encoder with bit rate constraint, of the type including: a capture buffer memory storing frames waiting to be processed; an encoding module receiving frames issued from the capture buffer memory and delivering compressed frames; an intermediate buffer memory, storing the compressed frames issued from the encoding module; and an emission buffer memory, storing data packets, resulting from the division of the compressed frames issued from the intermediate buffer memory, and emitting, with a controlled bit rate, the data packets on a communication channel. The encoder includes a control module, which dynamically adjusts the maximum size of the capture buffer memory, permitting the maximum size of the capture buffer memory to be temporarily increased as long as the emission buffer memory is not empty.

Abstract: A method is proposed for encoding/decoding an image having rectangular blocks of pixels. The image has a height of H blocks and a width of W blocks and is divided into vertical (or horizontal) bands of blocks having the height of H (or width of W) blocks. The method includes: obtaining N processors and M coprocessors, the M coprocessors distributed over S levels, N>1, S>0 and M>S; assigning the N processors Pi to N contiguous bands BPi having sizes of Ki blocks, 0?i?N?1 and ? i = 0 N - 1 ? ? K i = W ; for every level of coprocessors s, 0?s?S?1, assigning Ms coprocessors CPs,j to Ms contiguous bands having sizes of Qs,j blocks, with: ? j = 0 M s - 1 ? ? Q s , j = W ; managing sending of first, second and third start messages, and first and second verification messages to the processors and coprocessors, according to a predetermined set of rules.

Abstract: Method and apparatus for detecting transitions in a video sequence, which include detecting an abrupt transition including, for each image It?2k included in said video sequence and with a processing time rank t?2k: calculating a first distance D(It?k), between an image It?k and a reference image for said image It?k, which precedes said image It?k in the video sequence; calculating a second distance D(It?2k), between an image It?2k and a reference image for said image It?2k, which precedes said image It?2k in the video sequence; calculating a third distance D(It?3k), between an image It?3k and a reference image for said image It?3k, which precedes said image It?3k in the video sequence; calculating a criterion C? indicating whether said second distance D(It?2k) is significantly greater than the largest of the first and third distances, D(It?k) and D(It?3k); deciding, according to said criterion C?, on the belonging of the image It?2k to an abrupt transition.

Abstract: A method and apparatus are provided for coding or decoding an image comprising macro-blocks which are distributed in lines and columns. The processing of at least one given macro-block requires the pre-processing of at least one other macro-block on which said dependent macro-block depends. Moreover, the macro-blocks are processed sequentially line by line or column by column. Processing of the macro-blocks is multithreaded over N processors, N?2. The image is separated into N vertical bands each comprising a plurality of lines and at least one column of macro-blocks if the macro-block is processed sequentially line by line, or into N horizontal bands each comprising a plurality of columns and at least one line of macro-blocks if the macro-block is processed sequentially column by column. One of the N bands is processed by each processor, and the processing operations performed by the N processors is synchronized.

Abstract: A method is proposed for encoding/decoding an image having rectangular blocks of pixels. The image has a height of H blocks and a width of W blocks and is divided into vertical (or horizontal) bands of blocks having the height of H (or width of W) blocks. The method includes: obtaining N processors and M coprocessors, the M coprocessors distributed over S levels, N>1, S>0 and M>S; assigning the N processors Pi to N contiguous bands BPi having sizes of Ki blocks, 0?i?N?1 and ? i = 0 N - 1 ? ? K i = W ; for every level of coprocessors s, 0?s?S?1, assigning Ms coprocessors CPs,j to Ms contiguous bands having sizes of Qs,j blocks, with: ? j = 0 M s - 1 ? ? Q s , j = W ; managing sending of first, second and third start messages, and first and second verification messages to the processors and coprocessors, according to a predetermined set of rules.

Abstract: The invention provides interactive streaming mixed media production. A mixed media content creation tool includes a resource-computation element that computes the likely resource load to be imposed on a server, communication link, and client device, when sent by the server to the client and presented to a user at the client. The resource-computation element is responsive to amounts of communication bandwidth available using the communication link, presentation buffer space and computing resources available at the client, and other measures of resource load. The resource-computation element attempts to optimize resource usage by the mixed media content. The system also includes a presentation element that responds to the resource-computation element, and to user requests, and interactively presents measures of projected resource usage by the mixed media content, comparisons of that projected resource usage with available resources, and comparisons of that projected resource usage before and after optimization.

Abstract: A technique wherein the number and position of a quantization parameter node is determined in response to the quantization parameters and a preselected error. The size of scene graph and the corresponding amount of memory required to store the scene graph can be reduced by selective placement of quantization parameter nodes in a scene graph. The scene graph is traversed depth first to establish an order and then traversed in reverse. At each node, a calculation relating to (1) the relative cost of inserting a quantization parameter node and (2) the relative savings that result from insertion of a quantization node is performed. Quantization parameter nodes are selectively placed in response to a result of these calculations. The maximum degree of acceptable error value is chosen for each quantization type. This error value limits the number of quantization parameter nodes that can be placed in a scene graph.

Abstract: A method and system for rendering mixed media at a presentation workstation in response to a mixed media stream, in which the amount of computation is minimized. A tree structure includes nodes, each of which might point to sub-trees, and each of which designates a geometric object, a transformation to be applied to a geometric object, or a time-varying presentation. A scene includes nodes for each element in the scene. Depending from these would be nodes describing aspects of those elements, such as their texture and shape. A root node join the descriptions of each of the objects in the scene. Optimizing the amount of computation includes selecting nodes in the tree and calculating how to render each sub-tree. When possible, rendering information is calculated for only those portions of objects that will ultimately be shown to the user.

Abstract: The invention provides interactive streaming mixed media production. A mixed media content creation tool includes a resource-computation element that computes the likely resource load to be imposed on a server, communication link, and client device, when sent by the server to the client and presented to a user at the client. The resource-computation element is responsive to amounts of communication bandwidth available using the communication link, presentation buffer space and computing resources available at the client, and other measures of resource load. The resource-computation element attempts to optimize resource usage by the mixed media content. The system also includes a presentation element that responds to the resource-computation element, and to user requests, and interactively presents measures of projected resource usage by the mixed media content, comparisons of that projected resource usage with available resources, and comparisons of that projected resource usage before and after optimization.

Abstract: A real time encoder with bit rate constraint, of the type including: a capture buffer memory storing frames waiting to be processed; an encoding module receiving frames issued from the capture buffer memory and delivering compressed frames; an intermediate buffer memory, storing the compressed frames issued from the encoding module; and an emission buffer memory, storing data packets, resulting from the division of the compressed frames issued from the intermediate buffer memory, and emitting, with a controlled bit rate, the data packets on a communication channel. The encoder includes a control module, which dynamically adjusts the maximum size of the capture buffer memory, permitting the maximum size of the capture buffer memory to be temporarily increased as long as the emission buffer memory is not empty.

Abstract: A technique wherein the number and position of a quantization parameter node is determined in response to the quantization parameters and a preselected error. The size of scene graph and the corresponding amount of memory required to store the scene graph can be reduced by selective placement of quantization parameter nodes in a scene graph. The scene graph is traversed depth first to establish an order and then traversed in reverse. At each node, a calculation relating to (1) the relative cost of inserting a quantization parameter node and (2) the relative savings that result from insertion of a quantization node is performed. Quantization parameter nodes are selectively placed in response to a result of these calculations. The maximum degree of acceptable error value is chosen for each quantization type. This error value limits the number of quantization parameter nodes that can be placed in a scene graph.

Abstract: A multiple-reference motion-compensated predictive coding method is provided, which includes a multiple-reference motion estimation step, of the type making it possible to estimate the motion for each current frame included in a video sequence, from at least one initial list of reference frames for said current frame, each initial list LIi including Ni reference frames selected in a predetermined manner, with i>1 and Ni22 2. The multiple-reference motion estimation step includes the following steps for each current frame: for each initial list LIi, obtaining of a corresponding short list LRi by selecting ki reference frame(s) from among the Ni reference frames included in said initial list LIi, with 1<ki<Ni; and estimating motion based on the ki reference image(s) for each short list LRi. A flash frame detection step is performed based on the ki reference frame(s) selected for each short list LRi.

Abstract: Method and apparatus for detecting transitions in a video sequence, which include detecting an abrupt transition including, for each image It?2k included in said video sequence and with a processing time rank t=2k: calculating a first distance D(It?k), between an image It?k and a reference image for said image It?k, which precedes said image It?k in the video sequence; calculating a second distance D(It?2k), between an image It?2k and a reference image for said image It?2k, which precedes said image It?2k in the video sequence; calculating a third distance D(It?3k), between an image It?3k and a reference image for said image It?3k, which precedes said image It?3k in the video sequence; calculating a criterion C? indicating whether said second distance D(It?2k) is significantly greater than the largest of the first and third distances, D(It?k) and D(It?3k); deciding, according to said criterion C?, on the belonging of the image It?2k to an abrupt transition.

Abstract: A method and apparatus are provided for coding or decoding an image comprising macro-blocks which are distributed in lines and columns. The processing of at least one given macro-block requires the pre-processing of at least one other macro-block on which said dependent macro-block depends. Moreover, the macro-blocks are processed sequentially line by line or column by column. Processing of the macro-blocks is multithreaded over N processors, N?2. The image is separated into N vertical bands each comprising a plurality of lines and at least one column of macro-blocks if the macro-block is processed sequentially line by line, or into N horizontal bands each comprising a plurality of columns and at least one line of macro-blocks if the macro-block is processed sequentially column by column. One of the N bands is processed by each processor, and the processing operations performed by the N processors is synchronized.

Abstract: A technique wherein the number and position of a quantization parameter node is determined in response to the quantization parameters and a preselected error. The size of scene graph and the corresponding amount of memory required to store the scene graph can be reduced by selective placement of quantization parameter nodes in a scene graph. The scene graph is traversed depth first to establish an order and then traversed in reverse. At each node, a calculation relating to (1) the relative cost of inserting a quantization parameter node and (2) the relative savings that result from insertion of a quantization node is performed. Quantization parameter nodes are selectively placed in response to a result of these calculations. The maximum degree of acceptable error value is chosen for each quantization type. This error value limits the number of quantization parameter nodes that can be placed in a scene graph.

Abstract: A technique wherein the number and position of a quantization parameter node is determined in response to the quantization parameters and a preselected error. The size of scene graph and the corresponding amount of memory required to store the scene graph can be reduced by selective placement of quantization parameter nodes in a scene graph. The scene graph is traversed depth first to establish an order and then traversed in reverse. At each node, a calculation relating to (1) the relative cost of inserting a quantization parameter node and (2) the relative savings that result from insertion of a quantization node is performed. Quantization parameter nodes are selectively placed in response to a result of these calculations. The maximum degree of acceptable error value is chosen for each quantization type. This error value limits the number of quantization parameter nodes that can be placed in a scene graph.

Abstract: The invention provides interactive streaming mixed media production. A mixed media content creation tool includes a resource-computation element that computes the likely resource load to be imposed on a server, communication link, and client device, when sent by the server to the client and presented to a user at the client. The resource-computation element is responsive to amounts of communication bandwidth available using the communication link, presentation buffer space and computing resources available at the client, and other measures of resource load. The resource-computation element attempts to optimize resource usage by the mixed media content. The system also includes a presentation element that responds to the resource-computation element, and to user requests, and interactively presents measures of projected resource usage by the mixed media content, comparisons of that projected resource usage with available resources, and comparisons of that projected resource usage before and after optimization.