Abstract: Method and system for determining a measure of quality for images by using multi-level decomposition are presented. Multi-level decomposition of images is performed in the wavelet domain producing subbands at each level of decomposition. Aggregation of subbands is performed across multiple levels to produce an accurate measure of image quality. By aggregating only selected subbands the computational complexity of the method is greatly reduced.

Abstract: Method and system for determining a measure of quality for images are presented. Multi-level decomposition of images in the wavelet domain using a variable number of levels of decomposition and aggregation of selected subbands is performed to obtain an accurate measure of quality. The processing time is reduced in comparison to that required by other methods for generating measures of quality.

Abstract: A method and system for an efficient transcoding of a sequence of input images in a first format to a sequence of output images in a second format are described. The method utilizes the encoding block mode, the motion vectors and the residual information extracted during the decoding of the input image that are effectively reused to select an optimal transcoding block mode and to perform selective refinement of motion vectors. A corresponding system for video transcoding is also provided.

Abstract: A method and system for generation of a block mode conversion table for use in online transcoding of a sequence of input images in a first format to a sequence of output images in a second format are described. The table is based on a sequence of training images and provides an effective mapping between the encoding block modes and respective candidate transcoding block modes used during the online transcoding. The method utilizes the encoding block mode, the motion vectors and the residual information extracted during the decoding of the training image to generate the block mode conversion table. A corresponding system is also provided.

Abstract: A system and method for predicting a file size of an image subject to transformation by scaling and a change about at least one quality-controlling parameter, in which an input receives (a) the file size of the image before transformation, (b) information about at least one quality-controlling parameter of the image before transformation, (c) information about at least one quality-controlling parameter for application to the image during transformation, and (d) a scaling factor for application to the image during transformation. A relative size prediction is calculated on the basis of the received quality-controlling parameters information and scaling factor. The file size of the image after transformation is finally calculated as a function of the file size of the image before transformation and the calculated relative size prediction.

Abstract: Method and system for low complexity assessment of quality of an image are presented. By performing multiresolution decomposition of images using, for example, a discrete wavelet transform, and determining a metric based on a structural similarity index or a structural similarity map, a structural similarity score, characterizing similarity between images with a high degree of accuracy, is produced. The processing time is much smaller in comparison to that required by other methods producing image quality metrics of comparable accuracy.

Abstract: A device and method of controlling bitrate in video coding of a sequence of frames including series of Inter frames separated by Intra frames, wherein the coded frames are validated in a video buffering device prior to transmission of the coded frames and wherein the method comprises: measuring frame complexity in the sequence of frames; for each Inter frame, calculating a target buffer level of the video buffering device in relation to a distance between the Inter frame and a next Intra frame; for each Inter frame, calculating a target frame size in relation to the distance between the Inter frame and the next Intra frame, the measured frame complexity, a current buffer level of the video buffering device and the calculated target buffer level of the video buffering device; and using the calculated target frame size to control bitrate in video coding of the sequence of frames.

Abstract: Method and system for low complexity transcoding of images with near optimal quality for display on a terminal are presented. Generating effective transcoding parameters prior to transcoding and retrieving the transcoding parameters based on the features of the input image and the characteristics of the terminal, an output image quality close to that produced by optimal quality transcoding is achieved. The processing time is much smaller in comparison to that required for optimal quality transcoding.

Abstract: A method and device for improving rate controlling in video coding of sequences including a series of Inter frames separated by Intra frames, when a decoding delay is considered, comprise for each Inter frame of the series: computing a target frame size, computing a maximum buffer level related to a position of each Inter frame relative to a previous Intra frame and an upcoming Intra frame, and optimizing a transmission buffer level in response to the computed target frame size and the computed maximum buffer level.

Abstract: A system and method for conveying content-specific characteristics related to terminal capabilities and user preferences, and adapting content for particular terminals in response to the conveyed information. A content type or other message characteristic that is recognizable by the terminal is identified, as are operational confines of the terminal by which the content type is to comply. The content type is associated with the operational confines of the terminal. The content type and associated operational confines are provided to the network server for use by the network server in delivering messages to the terminal as dictated by the operational confines.

Abstract: A method an system for establishing a multi-user communication session, having a session description, between terminals with incompatible media characteristics, in which users with terminals having incompatible media characteristics are invited to participate in the communication session. A transcoding session is set up for enabling transcoding between the incompatible media characteristics of the terminals based on information about the terminals of the users having accepted the invitation, this information comprising the media characteristics of the users' terminals. The session description is established according to the transcoding session and, during the communication session, media streams from the terminal of one user are transcoded according to the transcoding session and the transcoded media streams are transmitted according to the session description to the other users participating in the communication session, using the media characteristics of the terminals of those other users.

Abstract: Several quality-aware transcoding systems and methods are described, in which the impact of both quality factor (QF) and scaling parameter choices on the quality of transcoded images are considered in combination. A basic transcoding system is enhanced by the addition of a quality prediction look-up table, and a method of generating such a table is also shown.

Abstract: Several quality-aware transcoding systems and methods are described, in which the impact of both quality factor (QF) and scaling parameter choices on the quality of transcoded images are considered in combination. A basic transcoding system is enhanced by the addition of a quality prediction look-up table, and a method of generating such a table is also shown.

Abstract: A method and apparatus is provided for transcoding content communicated in a network. The method features the step of transcoding the content based on permissible transcoding operations authorized by a content creator. The permissible transcoding operations include any transformation, alteration or manipulation of the content. The permissible transcoding operations include: a resolution reduction for reducing a resulting resolution of the content; an aspect ratio modification for specifying a maximum deformation that can be applied to the content when modifying its resolution; a color and bits per pixel modification for specifying if an image can be converted to gray scale or not, and minimum bits per pixel (bpp) or number of colors (or levels) that can be used; cropping for specifying a region of an original picture that must be preserved; and a quality reduction for allowing the content to be further modified by adding some distortions to an image. The content may be images, graphics, video or audio.

Abstract: This invention describes an adaptation system providing terminal-specific uniform resource locators (URLs) of downloadable software allowing a receiving terminal to render originally unsupported components of multimedia messages. The URLs are provided to the receiving terminal by a multimedia messaging service center (MMSC) which identifies the URLs from its database using information on the receiving terminal capabilities (i.e. based on terminal model and software release) and possibly multipurpose internet mail extension (MIME) types of originally unsupported components in multimedia messages.

Abstract: A generic method and means for defining and identifying classes of adaptation and classes of content in transcoding processes. The generic nature of the method and means allow for description of large quantity of adaptation and content classes, which would accommodate MMS, as well as other network applications. In addition, the method and means provide for a network application to communicate the defined classes of adaptation to a transcoding routine along with an indication as to whether adaptation of media content falling into such classifications are permitted or denied. The method and means also provide for the transcoding routine to communicate to the network application information about the adaptation performed in relation to the classification. The invention also provides for classification of the content of media elements both prior to and post adaptation.

Abstract: A method and apparatus are provided for measuring a bit rate between a client and a server. In an embodiment of the invention, a number of bits included only within one or more transaction units are measured over a time period. The time period is a sum of time durations of each of the transaction units. In an embodiment of the invention, bit rate measurements are performed on a server and in another embodiment of the invention bit rate measurements are performed on a client. Embodiments of the invention include adapting, by the server, of content to be sent to the client based on the bit rate measurements. Embodiments of the invention further include reporting the measured bit rate to the server when the bit rate measurements are performed on the client. Other aspects of the invention include sending an indication of the measured bit rate and a desired bit rate to the server when bit rate measurements are performed in the client.

Abstract: The invention relates to a method for providing a terminal MS2 of a communications system with coded still image signals. In order to enable a further content adaptation for multimedia messages, it is proposed that the method comprises receiving coded video signals at a network element of said communications system, converting at least a part of said received coded video signals in said network element to coded still image signals, and delivering said coded still image signals to a terminal MS2 of said communication system. The computation required for said conversion can be minimized by exploiting the commonalities of video and still images compression methods that are based on the Discrete Cosine Transform scheme. Thus it is rendered possible to provide excerpts of transmitted video clips also to terminals not capable of handling at least this particular video clip. The invention equally relates to a corresponding communications system, network element and module for a network element.

Abstract: A method (and corresponding equipment) by which a multimedia message is sent from a sending terminal (21) via a messaging server (22)—such as a MMS Proxy-Relay in MMS or a SIP proxy server in SIP IM—to a receiving terminal (25) having limited multimedia capabilities, with the sending terminal (21) adapted to include a user agent (21a) for inserting, into the message, media characteristics of the message sufficient in detail to enable the messaging server (22) to determine whether the message should be transcoded based on actual or assumed multimedia capabilities of the receiving terminal (25), and with the messaging server (22) configured to read the media characteristics and decide whether the message should be transcoded based only on the inserted media characteristics and on actual or assumed multimedia capabilities of the receiving terminal (25). The media characteristics are advantageously inserted into the header of the message.

Abstract: A system and method is provided that allows proxy servers to receive capability and preference information concerning user agents (502 and 510) desiring to establish a media session. The proxy server compares the capabilities of the user agents and determines whether an incompatibility exists between them. In the event that an incompatibility does exist, the proxy server may invoke the services of an adaptation server (508) to provide the necessary adaptation required to allow the media session to proceed. The adaptation system allows either the terminating or originating proxy server to make the adaptation determination to allow the adaptation server to modify the offered media session descriptions so that the media streams may be routed through the adaptation server to adapt between incompatible media parameters.